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During the last two decades, a revolutionary scientific new age, based on the capacity to observe, characterize, manipulate and organize matter in the nanometric scale, is appearing. In this scale, physics, chemistry, materials science, computational theory, and engineering converge towards the same theoretical principles and experimental findings that are basically governed by the laws of the Quantum Mechanics. Nanotechnology involves these interdisciplinary knowledge areas and methodologies in order to study, manufacture and characterize functional structures with dimensions of tens of nanometers. In 2008, Spain, Portugal and France (through their respective networks NanoSpain, PortugalNano and C'Nano GSO) decided to join efforts in order that NanoSpain events facilitate the dissemination of knowledge and promote interdisciplinary discussions not only in Spain but among the different groups from Southern Europe. Other objectives will also be to enhance industrial participation and permit considering the situation of Nanoscience and Nanotechnology in the south of Europe. The NanoSpain2012 edition will be organised in Santander (Spain), again in collaboration with these 3 networks. In order to organise the various sessions and to select contributions, the meeting will be structured in the following thematic lines, but interactions among them will be promoted: • • • • • • • • • • • •

Graphene Nanobiotechnology/Nanomedicine Nanomaterials Nanochemistry Nanomagnetism Nanophotonics/NanoOptics/Plasmonics Nanotoxicology and Nanosafety Nanotubes NEMS / MEMS Scanning Probe Microscopies (SPM) Scientific Policy Simulation at the nanoscale

Thematic parallel sessions will also be organised to enhance information flow between participants and in particular: − − − −

Exchange information of current work in specific research areas Solve particular technological problems Look for areas of common ground between different technologies Provide contributions to specific reports

The following Thematic Sessions will be organised: 1. 2. 3. 4. 5. 6.

NanoBiotechnology Industrial – Nanotechnology for Automotion Applications NanoChemistry NanoOptics & NanoPhotonics Graphene / Nanotubes NanoToxicology & NanoSafety

Finally, thanks must be directed to the staff of all organising institutions whose hard work has helped the smooth organisation and planning of this conference. THE ORGANISING COMMITTEE

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Organising Committee Jean-Pierre Aime Xavier Bouju Fernando Briones Antonio Correia Pedro Echenique Fernando Moreno Emilio Prieto Juan José Saenz Josep Samitier Daniel Sanchez Portal

Universite Bordeaux I & C'Nano Grand Sud-Ouest (France) CEMES-CNRS & C'Nano Grand Sud-Ouest (France) CNM/IMM-CSIC (Spain) Conference Chairman - Fundación Phantoms (Spain) Donostia International Physics Center (Spain) Universidad de Cantabria (Spain) Centro Español de Metrologia - CEM (Spain) Universidad Autónoma de Madrid (Spain) IBEC/UB (Universidad de Barcelona) (Spain) UPV/EHU - DIPC (Spain)

Local Organising Committee Luis Fernández Barquín Francisco Gonzalez Jesús González Gómez Angel Mañanes Pérez Fernando Moreno José Mª Saiz Vega

Universidad de Cantabria (Spain) Universidad de Cantabria (Spain) Universidad de Cantabria (Spain) Universidad de Cantabria (Spain) Universidad de Cantabria (Spain) Universidad de Cantabria (Spain)

Advisory Board

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Sabino Azcarate Jaime Colchero Pedro Echenique Javier Méndez Rodolfo Miranda Pablo Ordejon Fernando Palacio Jose Mª Pitarke Emilio Prieto José Rivas Juan Jose Saenz Josep Samitier Conchita Solans Jaume Veciana Jose Luis Viviente

Tekniker (Spain) Universidad de Murcia (Spain) Donostia International Physics Center (Spain) ICMM-CSIC (Spain) Universidad Autónoma de Madrid (Spain) Universidad Autónoma de Barcelona (Spain) ICMA / CSIC / Universidad de Zaragoza (Spain) CIC nanoGUNE Consolider (Spain) Centro Español de Metrologia (Spain) Universidad de Santiago de Compostela (Spain) / INL (Portugal) Universidad Autonoma de Madrid (Spain) IBEC/UB (Universidad de Barcelona) Instituto de Investigaciones Químicas y Ambientales de Barcelona (Spain) Instituto de Ciencia de Materiales de Barcelona (CSIC) (Spain) Fundacion Inasmet (Spain)

Technical Organising Committee Carmen Chacon Viviana Estêvão Maite Fernandez Paloma Garcia Escorial Concepcion Narros Joaquín Ramón-Laca Jose Luis Roldan

Fundación Phantoms (Spain) Fundación Phantoms (Spain) Fundación Phantoms (Spain) Fundación Phantoms (Spain) Fundacion Phantoms (Spain) Fundación Phantoms (Spain) Fundación Phantoms (Spain)


Organisers

Gold Sponsors

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Sponsors


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Exhibitors

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NanoSpain 2012 Exhibitors

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Experts on scientific and biomedical instrumentation. nB nanoScale Biomagnetics is a technology based company dedicated to the production of scientific and biomedical instruments for induction heating experiments of nanostructured materials, whose main application is on Magnetic Hyperthermia. Formed in 2008 as a Spin Off Company coming from the University of Zaragoza, nB enters the market in 2010 with the DM100 Series: the integral, immediate and reliable solution for Magnetic Hyperthermia laboratory trials. nB nanoScale Biomagnetics is your ideal partner for your needs and initiatives on scientific and biomedical instrumentation. nB nanoScale Biomagnetics is instrumentation for your ideas.

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contact@nbnanoscale.com www.nbnanoscale.com

_______________________________________________________________ Raith manufactures stand alone electron and ion beam lithography instruments with dedicated imaging functionality. Product portfolio is complemented by ELPHY, the sophisticated pattern generator soft- and hardware retrofit, which extends your scanning electron microscope or focussed ion beam with unmatched patterning capabilities. Worldwide installation, personalized trainings, technology transfer and user networking are always included in Raith offers. Raith GmbH Konrad-Adenauer-Allee 8 (Phoenix-West) 44263 Dortmund - GERMANY Phone: +49 (0)231 / 95 004-0 Fax: +49 (0)231 / 95 004-460 sales@raith.com www.raith.com


_________________________________________________________________ Nanotec Electronica is one of the leading companies in the Nanotechnology Industry. In only ten years Nanotec Electronica has established itself as one of the strongest companies that design, manufacture and supply Scanning Probe Microscopes (SPM). Our highly qualified team uses cutting-edge technology in order to provide a cost-effective tool to gain access to the nanometer scale for both scientific and industrial communities. With its headquarters based in Spain and distributors located around the world, Nanotec ensures global presence and guarantees total customer satisfaction. Nanotec´s Cervantes FullMode Atomic Force Microscope (AFM) in its several configurations allows not only imaging samples with atomic precision but also the study of magnetic, electronic and mechanical properties at the nanoscale, making it a powerful tool for physicists, chemists, biologists and engineers willing to characterize their samples at the nanometer scale. Its robust design provides strong mechanical stability to ensure high imaging resolution, and its semi-automated and open design allows scientists to exploit the capability of SPM to its maximum for both research and academic purposes. Nanotec Electronica also provides Dulcinea Control Systems, with an open and modular design that facilitates interfacing with any other standard AFM/SNOM/STM system available in the market. Highly versatile, it allows different modes of operation from Contact Mode to Frequency Modulation Mode and lithography ensuring a reliable and accurate performance of all SPM systems. Nanotec has also developed and freely distributes SPM software WSxM. Its user-friendly interface ensures easy operation of SPM microscopes and data processing. WSxM is available for its free download at www.nanotec.es.

Centro Empresarial Euronova 3 Ronda de Poniente 12, 2Âş C 28760 Tres Cantos (Madrid) SPAIN Tel: +34-918043347 www.nanotec.es

__________________________________________________________________ Paralab is a new company in a Spanish market offering solutions for scientific instrumentation with special focus on materials characterization. At this moment our product range includes AFM/STM systems and Industrial Tomography instrumentation. Contact: Eng. Rui Soares rui.soares@paralab.pt

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_________________________________________________________________________

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MTB Spain, founded in October 1993, distributes and provides after sales service for leading manufacturers in the field of Spectroscopy, Lasers, Metrology and Surface Analysis Instrumentation.MTB Spectroscopy and Lasers division is the exclusive distributor of the following companies: 1. Horiba Jobin Yvon, world wide leader in Raman Spectrometers, Fluorometers, Elipsometers, CCD’s & ICCD’s, Monochromators, Gratings and Surface Plasmon Resonance Imaging system. 2. JDSU, one of the major manufacturers of Diode Lasers. 3. EKSPLA, European manufacturer of Solid State Lasers (Diode Pumped, OPO) and ns / ps Lasers for scientific applications. 4. Sacher Lasertechnik, leader in Littman/Metcalf and Littrow cavities Lasers, suitable for Raman, Fluorescence and Absorption Spectroscopy and atom cooling and trapping. 5. Light Conversion, the world leading manufacturer of continuously wavelength tunable ultrafast light sources based on TOPAS series of optical parametric amplifiers and frequency mixers and expert in Ultrafast laser technology. MTB Image, Test & Measurement division distributes: 1. Microtrac, pioneer in manufacturing light scattering particle size technology for over 35 years. 2. Cryogenics, one of the main manufacturers of high quality measurement systems and providing the highest magnetic fields (up top 25 Tesla) and lower temperatures (down to 10mK). 3. AIST-NT, the world’s fastest and most advanced scanning probe microscope. MTB not only provides equipments but also complete solutions for specific applications, combining different analysis techniques such as Raman, TCSPC Fluorescence, AFM, SNOM, TERS, Photoluminescence and SEM-Cathodoluminescence. www.mtb.es

____________________________________________ The Spanish Institute for Foreign Trade (ICEX) ("Instituto Español de Comercio Exterior") is the Spanish Government agency serving Spanish companies to promote their exports and facilitate their international expansion, assisted by the network of Spanish Embassy’s Economic and Commercial Offices and, within Spain, by the Regional and Territorial Offices. It is part of the Spanish Ministry of Industry, Tourism and Trade ("Ministerio de Industria, Turismo y Comercio"). España, Technology for life: www.spainbussiness.com www.icex.es The Phantoms Foundation (non-profit organisation) was established on November 26, 2002 (in Madrid, Spain) to provide high level Management profile to National and European scientific projects. The Phantoms Foundation works in close collaboration with Spanish and European Governmental Institutions such as MEC (Spanish Ministry of Science) and ICEX (Spanish Institute for Foreign Trade), or the European Commission to provide focused reports on Nanoscience & Nanotechnology related research areas (infrastructure needs, emerging research, etc.) and develop activities to stimulate commercial nanotechnology applications (Spanish Pavilion at nanotech2008). www.phantomsnet.net


_________________________________________________________ Iberlaser was setup in 1993, and is based in Madrid-Spain. Our principal mission statement is provide research Spanish market with the novel instrumentation and highly qualified servicing. Our lines of products include: − Bio-technology: BioAFM, Optical tweezers. Digital cameras and special software for microscopy. − Laser Technology. CW and pulsed lasers covering the range UV-VIS-IR − Low light Imaging: Digital cameras (CCDs, SCMOs EMCCDs) and imaging software packages − Solar Simulators and photovoltaic devices characterization − Spectroscopy: Lamps, monocromators, spectrographs and detectors (mono and multi channel). LIBs and Raman systems. Time resolved (TCSPC) and steady state spectrofluorimeters. − Surface chemistry: Molecular interaction studies and Interface analysis (QCM-D and SPR). Monolayers preparation and thin films characterization. (Dip coaters, LB, BAM, IRRAS, Rheometer). Tensiometers optical and force measurements.

Email: info@iberlaser.com Tel: 91 658 67 60 Fax: 91 654 17 00 Avda. Pirineos, 7 - Oficina 2-8b 28700 San Sebastián de los Reyes (Madrid) SPAIN www.iberlaser.es

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________________________________________________________________ The Catalan Institute of Nanotechnology (ICN) is a CERCA centre that was founded in 2003 by the Catalan government and Universitat Autònoma de Barcelona. It strives for the highest level of scientific excellence in nanoscience and nanotechnology. ICN works closely with universities, research centres, technology centres, the private sector, the scientific community and the general public. Research at ICN is performed by nine Research Groups led by principal investigators who are world renowned experts in their field. These groups are supported by teams of specialised technicians and engineers as well as ICN’s administrative staff. ICN will present two joint initiatives at NANOSPAIN 2012: the Centre for NanoBioSafety and Sustainability (CNBSS), and NANOARACAT. CNBSS was established by ICN and LEITAT Technological Centre. This new centre is dedicated to R&D in the management of risks associated with nanotechnology. CNBSS endeavours to improve safety and sustainable implementation of nanotechnology at an industrial level, and to alleviate unwarranted fears about nanotechnology. Nanoaracat is a collaborative agreement between the governments of the autonomous communities of Aragon and Catalonia, to initiate joint activities in the fields of Nanoscience and Nanotechnology (N&N). ICN coordinates the members from Catalonia. www.icn.cat


_______________________________________________________________ NanoInk provides direct write, tip-based desktop lithography instruments and services for micro and nanoscale patterning. The product portfolio optimizes the controllable deposition of many different materials from nanoscale tips, all under ambient conditions, to rapidly generate user defined multiplexed patterns with feature sizes as small as 50 nm or as large as 10 microns. The ability to design and create custom engineered and functionalized surfaces with nanometer scale precision and sub-cellular resolution enables cutting edge nanofabrication, nanochemistry and nanobiological applications. www.nanoink.net ________________________________________________________________

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ScienTec Ibérica, is the spanish branch of ScienTec France, its mission is to serve and attend the Iberian market from the office in Madrid. ScienTec, as a whole, is specialized in the distribution of rigorously selected scientific equipments focused in the field of Nano-micro surface analysis, providing you a complete solution for your experimental or metrological needs. With more than 10 years experience in Nanotechnology, our sales ingeniers will help you define the right tool and configuration, our application group will teach and help you run the machines and our after sales team will preventively maintain or repair your sistems. Your investment will be back up with a perfect combination of top level instruments with the know how and tool expertise in the distribution. By Nanocharacterization at ScienTec we mean: − Scanning Probe Microscopies: AFM – STM from Agilent Technologies − Optical Nanocaracterization: SNOM from Nanonics − Mechanical Nanocaracterization: NanoIndenter from Agilent (formerly MTS) − Digital Holographical Microscopy: from Lyncée Tec − Optical and mechanical profilometry: from KLA Tencor − Digital Fluorescence Optical Microscopy: from Till Photonics − Thin Film thickness: reflectrometers from Filmetrics − Accesories and SPM consumables. Our main principal, Agilent Technologies, a leading player in the SPM market, provides innovative scanning probe microscopy (SPM) solutions for all academic research and industrial applications. Agilent Technologies Microscopes are the preferred choice to measure in liquids, temperature variation, electrochemical conditions, enviromental control or high resolution measurements. The acquisition of the Nano Instruments business have strengthen Agilent’s portfolio of instrumentation for imaging, characterizing and quantifying nano-mechanical material properties. The internal research collaboration among the differents business units at Agilent are bringing new exciting techniques to the SPM industry such as the exclusive Scanning Microwave Microscopy (SMM). Further developments are in the pipeline. ScienTec Ibérica C/ Buenavista 4 Bajo 28250 Torrelodones (Madrid) Phone: 91-8429467 Fax: 902-875572 info@scientec.fr www.scientec.es


_____________________________________________________________ The Institute of Nanoscience of Aragon (INA) is an interdisciplinary research institute of the University of Zaragoza (Spain). INA is devoted to R&D in Nanoscience and Nanotechnology. Our activity is based on the processing and fabrication of structures at the nanoscale and the study of their applications in collaboration with companies and technological institutes from different areas. We are interested in new collaborations with companies or other research institutions. TRAIN2 project is aimed to make SUDOE Region a reference place for the development of nanoscience at European level. The project constitutes a new concept of transnational research in the emerging and important field of nanoscience and nanotechnology which will bring a better use of the research infrastructures, exploit their capacities trying to avoid overlapping and integrate the SUDOE region in the ERA. The University of Zaragoza is the main beneficiary of this project. The Advanced Microscopy Laboratory (LMA), represents a unique initiative nationally and internationally. Its aim is to provide the scientific community with the most advanced existing equipment and infrastructures in local probe and electron microscopy for the observation, characterisation, nanopatterning and handling of materials at atomic level, as well as a wide range of scientific tools devoted to characterization, processing and handling procedures at the nanometric scale. Its location within the Institute of Nanoscience of Aragon (INA) guarantees an environment of associate infrastructures and excellence scientific and technical human resources and boost research capacities in nanoscience. The LMA equipment, which includes two Transmission Electron Aberration-Corredted Microscopes (TITAN), is available for public and private research centers and for the industrial sector in general. www.unizar.es/ina/ina.htm

___________________________________________________________________ Mecwins is a newly established technological company with a strong focus on R&D. Our activity is highly driven by cutting-edge technology and frontline innovation. We are developing Nanotechnologies to an advanced stage where they can be applied to diversified fields, from MEMS characterization to clinical analysis. Our technology to inspect surfaces is based on the combination of automated two-dimensional scanning of a laser beam and the acquisition of the reflected laser beam on a photodetector. The association of both allows the reconstruction of the analyzed surface topography. Mecwins has designed a versatile and modulable platform, SCALA, making use of its technology to offer a product that makes possible progress in the field of nanotechnology. SCALA has 3 distinct modules which can be used in different research fields and approaches. 1. 3D images module: The Scala platform is able to obtain 3D images with nanometric resolution in topography 2. Dynamic module: Possibility of detecting mass by changes in the vibration frequency of nano– micro resonator 3. Liquids module Scala has a module that makes it possible to measure in liquid environment www.mecwins.com

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___________________________________________________________________ TELSTAR INSTRUMAT, S.L. develops high technology instrumentation sales for research and industry, offering suitable technological tools adapted to each application, in order to improve the scientific researches or productive processes of our clients. In these last few years, TELSTAR INSTRUMAT has strengthened its activities representing leading companies in Spain & Portugal in the following applications: − Surface and material characterisation and metrology − ThinFilm deposition systems − Vacuum and cryogenics instrumentation and technology − Radiometry and photometry TELSTAR INSTRUMAT, S.L. counts amongst its customers the principal Official Organisation Investigation Centres and private customers in the microelectronic, aerospace, automotive, optical, food and pharmaceutical industries and in innovative fields such as biotechnology and nanofabrication. Some of our principals that are specifically of interest for the attendees to this conference are listed below: − Veeco Instruments (SPM, Optical and Mechanical Profilers) − Sopralab (ellipsometry and thin film pororisty) − MicroMaterials Ltd (Nanoindentation Systems) − SPECS GmbH (Surface Analysis, XPS, AFM-STM in UHV) The company's head office is in Sant Cugat del Vallès (Barcelona) and it also has a branch office in Madrid.

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Avda. Alcalde Barnils, 70, 3ª Planta 08174 Sant Cugat del Vallès (Spain) Tel. +34 935 442 320 Fax. +34 935 442 911

C/ Santibáñez de Béjar, 228042 Madrid Tel. +34 913 717 511 Fax. +34 917 477 538 comercial@telstar-instrumat.com www.telstar-instrumat.com

____________________________________________________________ NT-MDT enjoys a 20-year history in instrumentation created specifically for nanotechnology research, leading the field in originality, quality, and high tech development. We strive for next-generation SPM technology, whether it be in pure modularity that allows a university or industrial lab to start with a cost-effective core product and build to a grand, multi-user research center or the ultimate amalgamation of SPM with related technologies that has resulted in ultramicrotomy for nanotomography and spectroscopy-based instruments that meld the world of imaging with the world of chemical analysis. NT-MDT offers expert service and applications development through more than 20 representative offices and distributor centers around the globe. There are two key branch offices opened in Limerick, Ireland providing the shipping and logistic service and in Eindhoven, The Netherlands covering sales for the European countries as well as a state of the art application lab. In the past five years, our installed base has grown to over 2000 instruments, promoting growth of both lab and research programs world-wide. Whether you are engaged every day in nano research or just contemplating it, coupling your specific scientific knowledge and expertise with our competence in instrument creation will produce the highest quality research results currently available. www.ntmdt.com


__________________________________________________________________ With more than 20 years experience, AVACTEC is in a unique position to offer the finest products and technical guidance for customers in Spain and Portugal looking for UHV and high-vacuum components, vacuum deposition equipment or gas abatement systems. AVACTEC is the exclusive distributor in Spain for companies such as: − Allectra - Electrical feedthroughs and other vacuum components − CS Clean Systems - Dry-bed gas abatement − Mantis Deposition - Vacuum deposition systems and coating services − UHV Design - UHV motion and heating products We also offer a complete range of deposition consumables such as sputter targets, evaporation materials, crucibles etc. info@avactec.es www.avactec.com

_______________________________________________________________ AlphaSIP is a Spanish SME, established in December 2008, as an innovative SME in the biotechnology field. The company is clearly focuses on the fabrication of diagnostic biochips based on nanotechnology. AlphaSIP’s technology is a system in a package, being capable of integrating biosensor assays in diagnostics. Our chip is the result of the combined efforts of Spanish Researchers and Harvard Tech. The technology developed can be applied in different areas and markets, but initially AlphaSIP targets the Life Science sector, where it has most of its expertise. The main products are Point of Care (POC) devices for an accurate, fast and reliable diagnostic of diseases, such as cardiovascular diseases, hematological diseases or infectious diseases. The founders and partners represent both fields of the industrial sector, and have strong experience both in corporate and scientific development, a multidisciplinary team that ensures quality results. AlphaSIP has been recognized as an Innovative and R&D promoting company, being granted different prices at regional and national level. These prices highlight the Company’s stress in innovation, such as the Premio IDEA 2009 (2nd price for the most innovative company), 2010 Premio Bancaja and the Creces Prize La Caixa for the Fastest Growing Company 2011, and finally has been awarded as the Top bio company in Europe by MIT. The Company is continuously searching to develop innovative technologies through international cooperation. As a result, AlphaSIP organized a 24 million EUR ENIAC consortium proposal. The project counts with partners such as J&J, NXP, CEA Leti and up to 30 members targeting the development of a European production line. AlphaSIP’s technology will be an important breakthrough for the molecular diagnostics field, contributing with low cost, robust and reliable diagnostics device and fostering personalized medicine. European Headquarters. Azalea 135 El Soto de la Moraleja, 28109. Madrid SPAIN +34 626 00 41 07 mroncales@alphasip.es

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Your Journey to the Nanoscale Begins Here For over 60 years, FEI has been a global leader in focused electron and ion beam microscopy technologies. From the most powerful, commercially-available microscope, the Titan™ G2 60-300 S/TEM, to the Magellan™, the first extreme high resolution (XHR) SEM, FEI produces innovative imaging solutions for the material science, life science, electronics and natural resource markets, revolutionizing your exploration and discovery at the nanoscale.

Learn more at FEI.com © 2011 FEI Company. We are constantly improving the performance of our products, so all specifications are subject to change without notice.


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Scientific Programme

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I: Invited Lecture (40 min. including discussion time) K: Keynote Lecture (30 min. including discussion time) O: Oral Presentation (20 min. including discussion time) PF: Poster Flash


SCIENTIFIC PROGRAM

Monday - February 27, 2012 08h00-09h00 09h00-09h20

Registration Opening

09h20-10h00 Nacho Pascual (Freie Universitat Berlin, Germany) p. 59 "Sensing elementary processes in a molecular junction through force and light spectroscopy" 10h00-10h40 Guy Feuillet (CEA-LETI, France) p. 49 "Wide band gap nanowires for LED applications" 10h40-11h40 Coffee Break – Poster Session & Instrument Exhibition Jose Manuel Barandiaran (Universidad del Pais Vasco (UPV/EHU) - Spain) 11h40-12h00 "Dielectric and magnetic properties in Co- and Ni- containing ferrite/poly(vilidene fluoride) p. 107 multiferroic nanocomposites" 12h00-12h20 Jorge Fernado Fernandez-Sanchez (University of Granada - Spain) p. 115 "One-Step Fabrication of Multifunctional Core-Shell Nanofibres by Co-Electrospinning" 12h20-12h40 Mauricio Morais de Lima (Materials Science Institute - Spain) p. 137 "Low temperature optical emission of WZ InAs NWs" 12h40-13h00 Pablo Garcia-Fernandez (Universidad Cantabria - Spain) p.119 "Highly-confined spin-polarized two-dimensional electron gas in SrTiO3/SrRuO3 superlattices" 13h00-13h30 Poster Flash Contributions 13h30-15h00 Cocktail Lunch / Poster Session 1 Rogerio Gaspar (University of Lisbon, Portugal) 15h00-15h40 "Translational research in Nanomedicine: 30 years of clinical practice, the Science, the regulatory path p. 51 and the challenges" 15h40-16h00 Jose M. Lagaron (Novel Materials and Nanotechnology Group, IATA-CSIC - Spain) p. 125 "Electrospinning of Biopolymers: Applications" 16h00-16h20 Marco Chiesa (IMM-CNM-CSIC - Spain) p. 109 "Detection of the Early Stage of Recombinational DNA Repair by Silicon Nanowire Transistors" 16h20-16h40 Mónica López-Fanarraga (Universidad de Cantabria - Spain) p. 129 "Exploiting the biomimetic properties of multiwall carbon nanotubes in cancer treatment" Robert Stokes (Nano Fabrication Systems Division - UK) 16h40-17h00 "Life science at the sharp end: recent developments in tip-based nanolithography in sensing, cell p. 151 biology and diagnostics" 17h00-17h50 Coffee Break – Poster Session & Instrument Exhibition Jaume Veciana (ICMAB - Spain) 17h50-18h10 "Soft organic thin films, based on nanostructured polymeric composites, as ultra sensitive p. 155 piezoresistive sensors for biomedical applications" Jose Manuel Pingarron (Universidad Complutense de Madrid - Spain) 18h10-18h30 "Functionalization of electrode surfaces with three-dimensional networks of electropolymerized gold p. 141 nanoparticles for biosensor design" Miguel Monge (Universidad de La Rioja - Spain) 18h30-18h50 "Synthesis of gold, silver and gold-silver nanostructures from organometallic precursors. plasmonic, p. 135 bactericidal and catalytic properties." 18h50-19h10 Jose Maria Alonso (CIC nanoGUNE Consolider - Spain) p. 103 "Integrated eBL Resist/Tobacco Mosaic Virus Structures for Micro- and Nanofluidics"

I I

O

O O O

19 I

O O O

O

O

O

O

O


Monday - February 27, 2012 (13h00-13h30) Poster-Flash Last Name Kangur

Name Triin

Organisation University of Tartu

Country Estonia

Topic NanoBiotechnology / Nanomedicine

"Chemical and topographic effects on fibroblasts" Echevarria Bonet Cristina CITIMAC, Universidad de Cantabria Spain "Field-dependence of the resistivity minimum in intermediate valence nanometric YbAl3"

Nanomagnetism

Horga Félix Universidad de Cantabria Spain "Magnetic polarization of finite zigzag single walled carbon nanotubes by Fe clusters"

Nanomagnetism

Fornaguera Cristina IQAC-CSIC Spain NanoMaterials "Formation of dexamethasone-loaded nanoparticle dispersions from nano-emulsions as inhaled anti-inflammatory drug delivery systems" Rosal Roberto University of Alcalá Spain NanoMaterials "Anti-biofouling efficiency of electrospun polylactic acid membranes doped with silver and copper nanoparticles supported on sepiolite"

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Sousa Célia IFIMUP-IN Porto University “Nanoporous alumina template assisted growth of nanotubes and nanowires”

Portugal

NanoMaterials

Nanotoxicology and Nanosafety "Exposure of the bivalve RUDITAPES PHILIPPINARUM to gold nanoparticles: Location study by electron microscopy" García

Carlos

ICMSE-CSIC

Spain

The 5 minutes Poster-Flash contribution consists of a 3 Power Point slides related with the presented poster.


SCIENTIFIC PROGRAM

Tuesday - February 28, 2012 09h00-09h40 Gian Bartolo Picotto (Istituto Nazionale di Ricerca Metrologica (INRIM), Italy) p. 61 "Tools and Metrology at the nanoscale" 09h40-10h20 Juergen Brugger (EPFL / Institute of Microengineering, Switzerland) p. 45 "Latest advances in nanostenciling" 10h20-11h20 Coffee Break – Poster Session & Instrument Exhibition 11h20-11h40 Alexander Chizhik (Universidad del Pais Vasco - Spain) p. 111 "Magnetization reversal in sub-micrometric Fe-rich glass covered wires" 11h40-12h00 M. Luisa Fdez-Gubieda (Universidad del País Vasco, UPV/EHU - Spain) p. 113 "Magnetic interactions and interface phenomena on FexAg100-x granular thin films" 12h00-12h20 Nikolay Usov (Universidad del País Vasco (UPV/EHU) - Spain) p. 153 "Dynamics of magnetic nanoparticle with cubic anisotropy in a viscous liquid" 12h20-12h40 Fernando Palacio (Instituto de Ciencia de Materiales de Aragón - Spain) p. 139 "Thermometry: a novel functionality for magnetic nanoparticles" 12h40-13h00 Lunch

I I

O O O O

Graphene – Chairman: Stephan Roche NanoBiotechnology – Chairman: Josep Samitier, Jesus M. De la Fuente & Elena Martinez Industrial - Nanotechnology for Automotion applications – Chairman: Antonio Correia, Jordi Reverter & 15h00-17h30 Fernando Moreno Nanochemistry – Chairman: Jaume Veciana & Nora Ventosa Nanophotonic & Nanooptic – Chairman: Juan Jose Saenz & Antonio Garcia Martin Nanotoxicology – Chairman: Enrique Navarro 17h30-18h00 Coffee Break – Poster Session & Instrument Exhibition 18h00-18h45 Transfer to Palacio de la Magdalena 19h00 20h00

Pedro Miguel Echenique (DIPC, Spain) - (Plenary talk)

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Reception at Palacio de la Magdalena

Thematic Session – NanoPhotonics & NanoOptics Coordinators: Juan Jose Saenz & Antonio Garcia Martin 15h00-15h20 Amal Akou (Laboratoire de Chimie de Coordination - France) p. 163 "Tunable Diffraction Devices Based On Spin Crossover Materials" 15h20-15h40 Rodrigo Alcaraz de la Osa (Universidad de Cantabria - Spain) p. 165 "Magneto-optical effects in nano-disks as a perturbation of the optical response" 15h40-16h00 Maysoun Douas (ICMM-CSIC - Spain) p. 181 "Nanoscale optical hydrophilic characterization" 16h00-16h30 Jose A. Sánchez-Gil (Instituto de Estructura de la Materia (CSIC), Spain) p. 95 "Single nanoparticle Plasmonics: Shape matters" 16h30-17h00 Manuel Marques (UAM - Spain) p. 91 "Plasmonic Nanoparticle Chain in a Light Field: A Resonant Optical Sail" 17h00-17h30 General discussion

O O O K K

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Thematic Session – Graphene Coordinator: Stephan Roche K 15h00-15h30 Enrique Diez (Universidad de Salamanca, Spain) p. 87 "Quantum nanosystems based on graphene" Nicolas Agrait (Universidad Autonoma de Madrid, Spain) K 15h30-16h00 K 16h00-16h30 Frank Koppens (ICFO, Spain) p. 89 "Graphene: a novel platform for capturing and manipulating light at the nanoscale" O 16h30-16h45 Elena del Corro (University Complutense de Madrid - Spain) p. 177 "Compression enhanced conductivity in carbon nanotubes" O 16h45-17h00 Michael Heinrich (Lightweight Structures and Polymer Technology - Germany) p. 183 "Process-related mechanical properties of conductive Nanocomposites based on CNT-filled Polypropylen" O 17h00-17h15 Rosa Menendez (INCAR-CSIC - Spain) p. 189 "Preparation of graphenic materials of different structure" O 17h15-17h30 Eden Morales-Narváez (Catalan Institute of Nanotechnology - Spain) p. 191 "Optical biosensors based on graphene" 17h30 Conclusions

Thematic Session – Nanobiotechnology Coordinators: Josep Samitier, Jesus M. De la Fuente & Elena Martinez

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K 15h00-15h30 Guillermo de la Cueva Méndez (BIONAND, Spain) p. 85 "Application of synthetic biology to the development of smart therapeutic nanosystems against cancer" Laura Bonel (CAPHER IDI S.L - Spain) O 15h30-15h50 "Design of a competitive electrochemical biosensor based on affinity reaction between deoxynivalenol and p. 171 its polyclonal antibody" Eugenio Bringas (Universidad de Cantabria - Spain) O 15h50-16h10 "Superparamagnetic core-shell nanoparticles: synthesis, characterization and application in targeted drug p. 173 delivery" Marta Marín Suárez del Toro (University of Granada - Spain) O 16h10-16h30 "Electrophoretic deposition to develop new optical sensing materials: application to a wireless oxygen p. 185 sensing microrobot" O 16h30-16h50 Miguel Roncales (AlphaSIP - Spain) p. 201 "Nanotechnology in the hemostasis laboratory" O 16h50-17h10 Juan Carlos Vidal (Universidad de Zaragoza - Spain) p. 205 "An electrochemical competitive biosensor for fumonisin B1 (FB1) based on a DNA" Elena Martinez (IBEC - Spain) O 17h10-17h30 "Cell behavior by the controlled immobilization of biotinylated proteins in a gradient fashion: non-linear p. 187 concentration effects produced by unnoticed ligand nanoclustering" 17h30 Conclusions


Thematic Session – Industrial - Nanotechnology for Automotion applications Coordinators: Antonio Correia, Jordi Reverter & Fernando Moreno 15h00-15h30 Bartolomé Simonet (SINATEC, Spain)

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15h30-16h00 Claudio Sánchez Acevedo (TECNAN - Spain)

K

16h00-16h30 Pilar Merino (Grupo Antolin, Spain)

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16h30-17h00 Speaker to be defined

K

17h00-17h30 Speaker to be defined

K

17h30

Conclusions

Thematic Session – Nanochemistry Coordinators: Jaume Veciana & Nora Ventosa K 15h00-15h30 Ramon Martinez Máñez (UPV, Spain) p. 93 "Gated Materials in Delivery Applications" O 15h30-15h45 Núria Crivillers (ICMAB-CSIC - Spain) p. 179 "Electronic structure influence on the conductivity through open- and closed-shell molecules" K 15h45-16h15 Guillem Aromi (Universitat de Barcelona, Spain) p. 83 "Molecules as Prototypes for Spin-Based CNOT and SWAP Quantum Gates" Celia Rogero (Centro de Física de Materiales (CSIC-UPC/EHU) - Spain) O 16h15-16h30 "Intermolecular H-Bonding for Porphyrin Molecules on Surfaces: experimental evidences and theoretical p. 199 investigation" K 16h30-17h00 Felix Zamora (Universidad Autonoma de Madrid, Spain) p. 97 "Functional nanomaterials inspired in coordination polymers" O 17h00-17h15 Nora Ventosa (ICMAB - Spain) p. 203 "Compressed fluids: unique media for preparing vesicles with high structural homogeneity" 17h15-17h30 General discussion

Thematic Session – Nanotoxicology and Nanosafety Coordinator: Enrique Navarro O 15h00-15h20 Constança Porredon Guarch (Parc Científic de Barcelona - Spain) p. 195 "Need for guidelines specifically adapted for the toxicity testing of nanomaterials" Juan Ramon Castillo (Universidad de Zaragoza - Spain) O 15h20-15h40 "The frontier of the Environmental Analytical Nanotechnology Single Nanoparticle Detection by ICP-Mass p. 175 Spectrometry Cell Toxicity and Genotoxic Assays" O 15h40-16h00 Enrique Navarro (Instituto Pirenaico de Ecología (CSIC) - Spain) p. 193 "Assessing ionic silver availability to algae from differently coated silver nanoparticles" O 16h00-16h20 Ismael Rodea Palomares (Universidad Autónoma de Madrid - Spain) p. 197 "Assessment of nanoceria toxicity in aquatic photosynthetic organisms" Carlos Garcia Negrete (ICMSE-CSIC, Spain) PF 16h20-16h30 "Exposure of the bivalve RUDITAPES PHILIPPINARUM to gold nanoparticles: Location study by electron microscopy" Julian Blasco (Instituto Ciencias Marinas Andalucia (CSIC) - Spain) O 16h30-16h50 "Assessing toxicity of citrate-gold nanoparticles at different marine trophic levels (microalgae, copepods p. 169 and bivalve mollusks)" O 16h50-17h10 Lamiaa M. A. Ali (Universidad de Zaragoza - Spain) p. 167 "In vitro toxicity studies of polymer coated superparamagnetic iron oxide nanoparticles" 17h10-17h30 General discussion

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SCIENTIFIC PROGRAM

Wednesday - February 29, 2012 (Session:TRAIN2 / CNano GSO) 09h00-09h30 Isabelle Dufour (Université de Bordeaux, France) p. 71 "Measurement of Rheological Fluid Properties using MEMS" 09h30-10h00 Anne Hemeryck (CNRS/LAAS, France) p. 47 "Nanostructured Energetic Materials: Fabrication process and atomic scale modeling" 10h00-10h30 Elisabeth Garanger (Université de Bordeaux, France) p. 73 "Peptides in the design of theranostic nanocarriers" 10h30-11h00 Alexander Bittner (CIC nanoGUNE (Donostia) and Ikerbasque (Bilbo) - Spain) p. 67 "Peptide fibers: Electrospinning from solutions, molecular vibrational analysis" 11h00-11h30 Poster Session / Coffee Break & Instrument Exhibition Session: TRAIN2 / CNano GSO) 11h30-12h00 Jacques Bonvoisin (CEMES-CNRS, France) p. 69 "Progress towards SWAP single molecule – A chemical approach" 12h00-12h30 Renaud Vallée (Centre de Recherche Paul Pascal (CNRS), France) p. 79 "Colloidal architectures for plasmonics" 12h30-13h00 Sandra Garcia-Gil (CEMES-CNRS, France) p. 75 "DFT characterization of solid surfaces: interpretation of XPS experiments and H adsorption on silicates" 13h00-13h40 Quentin Pankhurst (The Royal Institution of Great Britain, UK) p. 57 "Translational R&D in Healthcare Biomagnetics" 13h40-15h00 Cocktail Lunch – Poster Session 2 15h00-15h20 Maria J. Lopez (Universidad de Valladolid - Spain) p. 127 "Hydrogen storage on Palladium doped nanoporous carbons" 15h20-15h40 Vyacheslav Silkin (Donostia Int. Physics Center - Spain) p. 149 "Electronic Structure of Graphene" 15h40-16h00 Amaia Zurutuza (Graphenea - Spain) p. 159 "Synthesis and Characterization of Graphene" 16h00-16h20 Juan José Vilatela (IMDEA Materials - Spain) p. 157 "Multifunctional Composites Based on Nanocarbons" 16h20-17h20 Coffee Break – Poster Session & Instrument Exhibition Stephan Roche (ICN, Spain) (Graphene Flagship presentation) 17h30-18h10 Stephan Roche (ICN, Spain) p. 63 "Transport Properties in Disordered Graphene: Effects of Atomic Hydrogen and Structural Defects" 18h10-18h50 Max Lemme (KTH, Sweden) p. 53 "Potential Applications for Graphene Devices in Nanoelectronics" 17h20-17h30

21h00

Conference Dinner

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O O O O

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SCIENTIFIC PROGRAM

Thursday - March 01, 2012 09h00-09h20 Fernando López-Tejeira (Instituto de Estructura de la Materia (IEM-CSIC) - Spain) p. 131 "Plasmonic Fano resonances become single-particle" 09h20-09h40 Pablo Albella Echave (Centro de Física de Materiales de San Sebastian (CSIC-UPV) - Spain) p. 101 "Plasmonic Antennas: From Optics to THz" 09h40-10h00 Pablo Alonso-González (CIC nanoGUNE Consolider - Spain) p. 105 "Real-Space Mapping of Fano Interference in Plasmonic Metamolecules" 10h00-10h20 Antonio Garcia-Martin (IMM-CNM-CSIC - Spain) p. 121 "High magneto-optical performance in metal-dielectric magnetoplasmonic nanodisks" 10h20-11h00 Henry Everitt (Duke University, USA) p. 47 "Ultraviolet Nanoplasmonics: Materials and Applications" 11h00-11h30 Coffee Break Raquel Gómez Medina (UAM - Spain) 11h30-11h50 "Electric and magnetic dipolar response of small dielectric particles: angle-suppressed scattering and p. 123 optical forces" Yury Rakovich (Centro de Fisica de Materiales (CSIC-UPV/EHU) - Spain) 11h50-12h10 "Optical enhancement effect in metal-organic nanohybrids integrated with whispering-galery-mode p. 143 microcavities" 12h10-12h30 Juan Marcos Sanz Casado (Universidad de Cantabria - Spain) p. 147 "Light Depolarization in Nanosphere-Dimers by Incoherent Mixing of Mueller Matrices" Aritz Retolaza (TEKNIKER-IK4 - Spain) 12h30-12h50 "Efficient organic distributed feedback lasers with active films imprinted by thermal nanoimprint p. 145 lithography" 12h50-13h10 Braulio Garcia-Camara (Universidad de Cantabria - Spain) p. 117 "Polarization Properties of the Scattered Radiation by Silicon Nanoparticles in the Infrared" 13h10-13h50 Onofrio Maragò (Consiglio Nazionale delle Ricerche, Italy) p. 55 "Optical Trapping of Nanostructures: Femtonewton Force Sensing and Ultra-Sensitive Spectroscopy" 13h50

Concluding Remarks / NanoSpain2013 announcement

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Abstracts

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INDEX Plenary Speakers (1) Pedro Miguel Echenique (DIPC, Spain)

Invited Speakers -Plenary Session (10) Page Juergen Brugger (EPFL / Institute of Microengineering, Switzerland) "Latest advances in nanostenciling"

45

Henry Everitt (Duke University, USA) "Ultraviolet Nanoplasmonics: Materials and Applications"

47

Guy Feuillet (CEA-LETI, France) "Wide band gap nanowires for LED applications"

49

Rogerio Gaspar (University of Lisbon, Portugal) "Translational research in Nanomedicine: 30 years of clinical practice, the Science, the regulatory path and the challenges"

51

Max Lemme (KTH, Sweden) "Potential Applications for Graphene Devices in Nanoelectronics"

53

Onofrio Maragò (Consiglio Nazionale delle Ricerche, Italy) "Optical Trapping of Nanostructures: Femtonewton Force Sensing and Ultra-Sensitive Spectroscopy"

55

Quentin Pankhurst (The Royal Institution of Great Britain, UK) "Translational R&D in Healthcare Biomagnetics"

57

Nacho Pascual (Freie Universitat Berlin, Germany) "Sensing elementary processes in a molecular junction through force and light spectroscopy"

59

Gian Bartolo Picotto (Istituto Nazionale di Ricerca Metrologica (INRIM), Italy) "Tools and Metrology at the nanoscale"

61

Stephan Roche (ICN, Spain) "Transport Properties in Disordered Graphene: Effects of Atomic Hydrogen and Structural Defects"

63

Keynotes Speakers (CNano GSO / TRAIN2 Session) - Plenary Session (7) Page Alexander Bittner (CIC nanoGUNE (Donostia) and Ikerbasque (Bilbo) - Spain) "Peptide fibers: Electrospinning from solutions, molecular vibrational analysis"

67

Jacques Bonvoisin (CEMES-CNRS, France) "Progress towards SWAP single molecule – A chemical approach"

69

Isabelle Dufour (Université de Bordeaux, France) "Measurement of Rheological Fluid Properties using MEMS"

71

Elisabeth Garanger (Université de Bordeaux, France) "Peptides in the design of theranostic nanocarriers"

73

Sandra García-Gil (CEMES-CNRS, France) "DFT characterization of solid surfaces: interpretation of XPS experiments and H adsorption on silicates"

75

31


Page Anne Hemeryck (CNRS/LAAS, France) "Nanostructured Energetic Materials: Fabrication process and atomic scale modeling"

77

Renaud Vallée (Centre de Recherche Paul Pascal (CNRS), France) "Colloidal architectures for plasmonics"

79

Keynote Speakers - Parallel Sessions (12)

Nicolas Agrait (Universidad Autónoma de Madrid, Spain) Graphene / Nanotubes

32

Page -

Guillem Aromi (Universitat de Barcelona, Spain) NanoChemistry Molecules as Prototypes for Spin-Based CNOT and SWAP Quantum Gates"

83

Guillermo de la Cueva Méndez (BIONAND, Spain) NanoBiotechnology / Nanomedicine "Application of synthetic biology to the development of smart therapeutic nanosystems against cancer"

85

Enrique Díez (Universidad de Salamanca, Spain) Graphene / Nanotubes "Quantum nanosystems based on graphene"

87

Frank Koppens (ICFO, Spain) Graphene / Nanotubes "Graphene: a novel platform for capturing and manipulating light at the nanoscale"

89

Manuel Marqués (UAM - Spain) Nanophotonics/NanOptics/Plasmonics "Plasmonic Nanoparticle Chain in a Light Field: A Resonant Optical Sail"

91

Ramón Martinez Máñez (UPV, Spain) NanoChemistry "Gated Materials in Delivery Applications"

93

Pilar Merino (Grupo Antolin, Spain),Industrial - Nanotechnology for Automotion application

-

Claudio Sánchez Acevedo (TECNAN - Spain) Industrial Nanotechnology for Automotion applications

-

José A. Sánchez-Gil (Instituto de Estructura de la Materia (CSIC), Spain) Nanophotonics/ NanOptics/Plasmonics “Single nanoparticle Plasmonics: Shape matters" Bartolomé Simonet (SINATEC, Spain) Industrial - Nanotechnology for Automotion applications Félix Zamora (Universidad Autonoma de Madrid, Spain) NanoChemistry "Functional nanomaterials inspired in coordination polymers"

95 97


Orals - Plenary Session - Plenary Session (30) Page Pablo Albella Echave (Centro de Física de Materiales de San Sebastian (CSIC-UPV) - Spain) Nanophotonics "Plasmonic Antennas: From Optics to THz"

101

José María Alonso (CIC nanoGUNE Consolider - Spain)NanoChemistry "Integrated eBL Resist/Tobacco Mosaic Virus Structures for Micro- and Nanofluidics"

103

Pablo Alonso-González (CIC nanoGUNE Consolider - Spain) Nanophotonics/NanOptics/Plasmonics "Real-Space Mapping of Fano Interference in Plasmonic Metamolecules"

105

José Manuel Barandiarán (Universidad del Pais Vasco (UPV/EHU) - Spain) NanoMaterials "Dielectric and magnetic properties in Co- and Ni- containing ferrite/poly(vilidene fluoride) multiferroic nanocomposites"

107

Marco Chiesa (IMM-CNM-CSIC - Spain) NanoBiotechnology / Nanomedicine "Detection of the Early Stage of Recombinational DNA Repair by Silicon Nanowire Transistors"

109

Alexander Chizhik (Universidad del Pais Vasco - Spain) Nanomagnetism "Magnetization reversal in sub-micrometric Fe-rich glass covered wires"

111

M. Luisa Fdez-Gubieda (Universidad del País Vasco, UPV/EHU - Spain) Nanomagnetism "Magnetic interactions and interface phenomena on FexAg100-x granular thin films"

113

Jorge Fernando Fernández-Sánchez (University of Granada - Spain) NanoMaterials "One-Step Fabrication of Multifunctional Core-Shell Nanofibres by Co-Electrospinning"

115

33

Braulio Garcia-Camara (Universidad de Cantabria – Spain) Nanophotonics/NanOptics/Plasmonics "Polarization Properties of the Scattered Radiation by Silicon Nanoparticles in the Infrared"

117

Pablo García-Fernández (Universidad Cantabria - Spain) Simulation at the nanoscale "Highly-confined spin-polarized two-dimensional electron gas in SrTiO3/SrRuO3 superlattices"

119

Antonio García-Martín (IMM-CNM-CSIC - Spain) Nanophotonics/NanOptics/Plasmonics "High magneto-optical performance in metal-dielectric magnetoplasmonic nanodisks"

121

Raquel Gómez Medina (UAM - Spain) Nanophotonics/NanOptics/Plasmonics "Electric and magnetic dipolar response of small dielectric particles: angle-suppressed scattering and optical forces"

123

Jose M. Lagarón (Novel Materials and Nanotechnology Group, IATA-CSIC - Spain) NanoMaterials "Electrospinning of Biopolymers: Applications"

125

María J. López (Universidad de Valladolid - Spain) Graphene "Hydrogen storage on Palladium doped nanoporous carbons"

127

Mónica López-Fanarraga (Universidad de Cantabria - Spain) NanoBiotechnology / Nanomedicine "Exploiting the biomimetic properties of multiwall carbon nanotubes in cancer treatment"

129

Fernando López-Tejeira (Instituto de Estructura de la Materia (IEM-CSIC) - Spain) Nanophotonics/ NanOptics/Plasmonics "Plasmonic Fano resonances become single-particle"

131


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34

Amaia Martínez Muro (nanoBasque - Spain) Scientific Policy and Infrastructure "NanoBasque Strategy: Basque Country´s strategic bid for nanoscience, micro and nanotechnologies"

133

Miguel Monge (Universidad de La Rioja - Spain) NanoChemistry "Synthesis of gold, silver and gold-silver nanostructures from organometallic precursors, plasmonic, bactericidal and catalytic properties."

135

Mauricio Morais de Lima (Materials Science Institute - Spain) NanoMaterials "Low temperature optical emission of WZ InAs NWs"

137

Fernando Palacio (Instituto de Ciencia de Materiales de Aragón - Spain) NanoMaterials "Thermometry: a novel functionality for magnetic nanoparticles"

139

José Manuel Pingarrón (Universidad Complutense de Madrid - Spain) NanoChemistry "Functionalization of electrode surfaces with three-dimensional networks of electropolymerized gold nanoparticles for biosensor design"

141

Yury Rakovich (Centro de Fisica de Materiales (CSIC-UPV/EHU) – Spain Nanophotonics/ NanOptics/Plasmonics "Optical enhancement effect in metal-organic nanohybrids integrated with whispering-galerymode microcavities"

143

Aritz Retolaza (TEKNIKER-IK4 - Spain) Nanophotonics/NanOptics/Plasmonics "Efficient organic distributed feedback lasers with active films imprinted by thermal nanoimprint lithography"

145

Juan Marcos Sanz Casado (Universidad de Cantabria - Spain) Nanophotonics/ NanOptics/ Plasmonics "Light Depolarization in Nanosphere-Dimers by Incoherent Mixing of Mueller Matrices"

147

Vyacheslav Silkin (Donostia Int. Physics Center - Spain) Graphene "Electronic Structure of Graphene"

149

Robert Stokes (Nano Fabrication Systems Division - UK) NanoBiotechnology / Nanomedicine "Life science at the sharp end: recent developments in tip-based nanolithography in sensing, cell biology and diagnostics"

151

Nikolay Usov (Universidad del País Vasco (UPV/EHU) - Spain) Nanomagnetism "Dynamics of magnetic nanoparticle with cubic anisotropy in a viscous liquid"

153

Jaume Veciana (ICMAB - Spain) NanoChemistry "Soft organic thin films, based on nanostructured polymeric composites, as ultra sensitive piezoresistive sensors for biomedical applications"

155

Juan José Vilatela (IMDEA Materials - Spain) Nanotubes "Multifunctional Composites Based on Nanocarbons"

157

Amaia Zurutuza (Graphenea - Spain) Graphene "Synthesis and Characterization of Graphene"

159


Orals - Parallel Sessions (22) Page Amal Akou (Laboratoire de Chimie de Coordination - France) Nanophotonics/NanOptics/Plasmonics "Tunable Diffraction Devices Based On Spin Crossover Materials"

163

Rodrigo Alcaraz de la Osa (Universidad de Cantabria - Spain) Nanophotonics/ NanOptics/Plasmonics "Magneto-optical effects in nano-disks as a perturbation of the optical response"

165

Lamiaa M. A. Ali (Universidad de Zaragoza - Spain) Nanotoxicology and Nanosafety "In vitro toxicity studies of polymer coated superparamagnetic iron oxide nanoparticles"

167

Julián Blasco (Instituto Ciencias Marinas Andalucia (CSIC) - Spain) Nanotoxicology and Nanosafety "Assessing toxicity of citrate-gold nanoparticles at different marine trophic levels (microalgae, copepods and bivalve mollusks)"

169

Laura Bonel (CAPHER IDI S.L - Spain) NanoBiotechnology / Nanomedicine "Design of a competitive electrochemical biosensor based on affinity reaction between deoxynivalenol and its polyclonal antibody"

171

Eugenio Bringas (Universidad de Cantabria - Spain) NanoBiotechnology / Nanomedicine "Superparamagnetic core-shell nanoparticles: synthesis, characterization and application in targeted drug delivery"

173

Juan Ramón Castillo (Universidad de Zaragoza - Spain) Nanotoxicology and Nanosafety "The frontier of the Environmental Analytical Nanotechnology Single Nanoparticle Detection by ICP-Mass Spectrometry Cell Toxicity and Genotoxic Assays"

175

Elena del Corro (University Complutense de Madrid - Spain) Nanotubes "Compression enhanced conductivity in carbon nanotubes"

177

Núria Crivillers (ICMAB-CSIC - Spain) NanoChemistry "Electronic structure influence on the conductivity through open- and closed-shell molecules"

179

Maysoun Douas (ICMM-CSIC - Spain) Nanophotonics/NanOptics/Plasmonics "Nanoscale optical hydrophilic characterization"

181

Michael Heinrich (Lightweight Structures and Polymer Technology - Germany) Nanotubes "Process-related mechanical properties of conductive Nanocomposites based on CNT-filled Polypropylen"

183

Marta Marín Suárez del Toro (University of Granada - Spain) NanoBiotechnology / Nanomedicine "Electrophoretic deposition to develop new optical sensing materials: application to a wireless oxygen sensing microrobot"

185

Elena Martínez (IBEC - Spain) NanoBiotechnology / Nanomedicine "Cell behavior by the controlled immobilization of biotinylated proteins in a gradient fashion: non-linear concentration effects produced by unnoticed ligand nanoclustering"

187

Rosa Menéndez (INCAR-CSIC - Spain) Graphene "Preparation of graphenic materials of different structure"

189

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36

Eden Morales-Narváez (Catalan Institute of Nanotechnology - Spain) Graphene "Optical biosensors based on graphene"

191

Enrique Navarro (Instituto Pirenaico de Ecología (CSIC) - Spain) Nanotoxicology and Nanosafet "Assessing ionic silver availability to algae from differently coated silver nanoparticles"

193

Constança Porredon Guarch (Parc Científic de Barcelona - Spain) Nanotoxicology and Nanosafety "Need for guidelines specifically adapted for the toxicity testing of nanomaterials"

195

Ismael Rodea Palomares (Universidad Autónoma de Madrid - Spain) Nanotoxicology and Nanosafety "Assessment of nanoceria toxicity in aquatic photosynthetic organisms"

197

Celia Rogero (Centro de Física de Materiales (CSIC-UPC/EHU) - Spain) NanoChemistry "Intermolecular H-Bonding for Porphyrin Molecules on Surfaces: experimental evidences and theoretical investigation"

199

Miguel Roncales (AlphaSIP - Spain) NanoBiotechnology / Nanomedicine "Nanotechnology in the hemostasis laboratory"

201

Nora Ventosa (ICMAB - Spain) NanoChemistry "Compressed fluids: unique media for preparing vesicles with high structural homogeneity"

203

Juan Carlos Vidal (Universidad de Zaragoza - Spain) NanoBiotechnology / Nanomedicine "An electrochemical competitive biosensor for fumonisin B1 (FB1) based on a DNA"

205


INDEX- Alphabetical Order Page Nicolas Agrait (Universidad Autónoma de Madrid, Spain) Graphene / Nanotubes

KEYNOTE Parallel Sessions

-

Amal Akou (Laboratoire de Chimie de Coordination - France) Nanophotonics/NanOptics/Plasmonics “Tunable Diffraction Devices Based On Spin Crossover Materials"

ORAL Parallel Sessions

163

Pablo Albella Echave (Centro de Física de Materiales de San Sebastian (CSICUPV) - Spain), Nanophotonics "Plasmonic Antennas: From Optics to THz"

ORAL Plenary Sessions

101

Rodrigo Alcaraz de la Osa (Universidad de Cantabria - Spain) Nanophotonics/NanOptics/Plasmonics "Magneto-optical effects in nano-disks as a perturbation of the optical response"

ORAL Parallel Sessions

165

Lamiaa M. A. Ali (Universidad de Zaragoza - Spain) ORAL Parallel Sessions Nanotoxicology and Nanosafety "In vitro toxicity studies of polymer coated superparamagnetic iron oxide nanoparticles"

167

ORAL Jose Maria Alonso (CIC nanoGUNE Consolider - Spain) Plenary Sessions NanoChemistry "Integrated eBL Resist/Tobacco Mosaic Virus Structures for Micro- and Nanofluidics"

103

Pablo Alonso-González (CIC nanoGUNE Consolider - Spain) Nanophotonics/NanOptics/Plasmonics "Real-Space Mapping of Fano Interference in Plasmonic Metamolecules"

ORAL Plenary Sessions

105

Guillem Aromi (Universitat de Barcelona, Spain) NanoChemistry "Molecules as Prototypes for Spin-Based CNOT and SWAP Quantum Gates"

KEYNOTE Parallel Sessions

83

José Manuel Barandiarán (Universidad del Pais Vasco (UPV/EHU) - Spain) ORAL Plenary Session NanoMaterials "Dielectric and magnetic properties in Co- and Ni- containing ferrite/poly(vilidene fluoride) multiferroic nanocomposites"

107

Alexander Bittner (CIC nanoGUNE (Donostia) and Ikerbasque (Bilbo) - Spain) CNano GSO / TRAIN2 "Peptide fibers: Electrospinning from solutions, molecular vibrational analysis"

67

KEYNOTE Plenary Sessions

Julián Blasco (Instituto Ciencias Marinas Andalucia (CSIC) - Spain) ORAL Parallel Sessions Nanotoxicology and Nanosafety "Assessing toxicity of citrate-gold nanoparticles at different marine trophic levels (microalgae, copepods and bivalve mollusks)"

169

Laura Bonel (CAPHER IDI S.L - Spain) ORAL Parallel Sessions NanoBiotechnology / Nanomedicine "Design of a competitive electrochemical biosensor based on affinity reaction between deoxynivalenol and its polyclonal antibody"

171

Jacques Bonvoisin (CEMES-CNRS, France) CNano GSO / TRAIN2 "Progress towards SWAP single molecule – A chemical approach"

KEYNOTE Plenary Sessions

69

37


Page Eugenio Bringas (Universidad de Cantabria - Spain) ORAL Parallel Session NanoBiotechnology / Nanomedicine "Superparamagnetic core-shell nanoparticles: synthesis, characterization and application in targeted drug delivery" Juergen Brugger (EPFL / Institute of Microengineering, Switzerland)

INVITED Plenary Sessions

"Latest advances in nanostenciling" ORAL Juan Ramón Castillo (Universidad de Zaragoza - Spain) Parallel Sessions Nanotoxicology and Nanosafety "The frontier of the Environmental Analytical Nanotechnology Single Nanoparticle Detection by ICP-Mass Spectrometry Cell Toxicity and Genotoxic Assas"

Marco Chiesa (IMM-CNM-CSIC - Spain) NanoBiotechnology / Nanomedicine

ORAL Plenary Session

"Detection of the Early Stage of Recombinational DNA Repair by Silicon Nanowire Transistors" Alexander Chizhik (Universidad del Pais Vasco - Spain) Nanomagnetism

179

177

KEYNOTE Parallel Sessions

87

ORAL Parallel Session

181

"Quantum nanosystems based on graphene" Maysoun Douas (ICMM-CSIC - Spain) Nanophotonics/ NanOptics/Plasmonics "Nanoscale optical hydrophilic characterization" Isabelle Dufour (Université de Bordeaux, France) CNano GSO / TRAIN2

KEYNOTE Plenary Sessions

"Measurement of Rheological Fluid Properties using MEMS" Henry Everitt (Duke University, USA)

85

ORAL Parallel Sessions

"Compression enhanced conductivity in carbon nanotubes" Enrique Diez (Universidad de Salamanca, Spain) Graphene / Nanotubes

109

ORAL Parallel Sessions

KEYNOTE Guillermo de la Cueva Méndez (BIONAND, Spain) Parallel Sessions NanoBiotechnology / Nanomedicine "Application of synthetic biology to the development of smart therapeutic nanosystems against cancer"

Elena del Corro (University Complutense de Madrid - Spain) Nanotubes

175

111

"Electronic structure influence on the conductivity through open- and closed-shell molecules"

38

45

ORAL Plenary Sessions

"Magnetization reversal in sub-micrometric Fe-rich glass covered wires" Núria Crivillers (ICMAB-CSIC - Spain) NanoChemistry

173

INVITED Plenary Sessions

"Ultraviolet Nanoplasmonics: Materials and Applications"

71

47

ORAL M. Luisa Fdez-Gubieda (Universidad del País Vasco, UPV/EHU - Spain) Plenary Sessions Nanomagnetism "Magnetic interactions and interface phenomena on FexAg100-x granular thin films"

113

ORAL Jorge Fernando Fernández-Sánchez (University of Granada - Spain) Plenary Sessions NanoMaterials "One-Step Fabrication of Multifunctional Core-Shell Nanofibres by Co-Electrospinning"

115


Page Guy Feuillet (CEA-LETI, France)

INVITED Plenary Session

49

KEYNOTE Plenary Sessions

73

"Wide band gap nanowires for LED applications" Elisabeth Garanger (Université de Bordeaux, France) CNano GSO / TRAIN2 "Peptides in the design of theranostic nanocarriers" ORAL Braulio García-Cámara (Universidad de Cantabria - Spain) Plenary Sessions Nanophotonics/NanOptics/Plasmonics "Polarization Properties of the Scattered Radiation by Silicon Nanoparticles in the Infrared"

117

ORAL Pablo García-Fernández (Universidad Cantabria - Spain) Plenary Sessions Simulation at the nanoscale "Highly-confined spin-polarized two-dimensional electron gas in SrTiO3/SrRuO3 superlattices"

119

Sandra Garcia-Gil (CEMES-CNRS, France)

CNano GSO / TRAIN2

KEYNOTE Plenary Sessions

"DFT characterization of solid surfaces: interpretation of XPS experiments and H adsorption on silicates" ORAL Antonio García-Martín (IMM-CNM-CSIC - Spain) Plenary Sessions Nanophotonics NanOptics/Plasmonics "High magneto-optical performance in metal-dielectric magnetoplasmonic nanodisks"

Rogerio Gaspar (University of Lisbon, Portugal)

INVITED Plenary Sessions

"Translational research in Nanomedicine: 30 years of clinical practice, the Science, the regulatory path and the challenges"

75

121

51

39

ORAL Raquel Gómez Medina (UAM - Spain) Plenary Session Nanophotonics /NanOptics/ Plasmonics "Electric and magnetic dipolar response of small dielectric particles: angle-suppressed scattering and optical forces"

123

ORAL Michael Heinrich (Lightweight Structures and Polymer Technology - Germany) Parallel Sessions Nanotubes "Process-related mechanical properties of conductive Nanocomposites based on CNT-filled Polypropylen"

183

Anne Hemeryck (CNRS/LAAS, France) CNano GSO / TRAIN2

KEYNOTE Plenary Sessions

"Nanostructured Energetic Materials: Fabrication process and atomic scale modeling" Frank Koppens (ICFO, Spain) Graphene / Nanotubes

KEYNOTE Parallel Sessions

"Graphene: a novel platform for capturing and manipulating light at the nanoscale"

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José M. Lagarón (Novel Materials and Nanotechnology Group, IATA-CSIC Spain) NanoMaterials "Electrospinning of Biopolymers: Applications"

ORAL Plenary Sessions

Max Lemme (KTH, Sweden)

INVITED Plenary Sessions

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"Potential Applications for Graphene Devices in Nanoelectronics" María J. López (Universidad de Valladolid - Spain) Graphene "Hydrogen storage on Palladium doped nanoporous carbons"

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Page ORAL Mónica López-Fanarraga (Universidad de Cantabria - Spain) Plenary Sessions NanoBiotechnology / Nanomedicine "Exploiting the biomimetic properties of multiwall carbon nanotubes in cancer treatment"

Fernando López-Tejeira (Instituto de Estructura de la Materia (IEM-CSIC) Spain) Nanophotonics/NanOptics/Plasmonics "Plasmonic Fano resonances become single-particle"

ORAL Plenary Sessions

Onofrio Maragò (Consiglio Nazionale delle Ricerche, Italy)

INVITED Plenary Sessions

"Optical Trapping of Nanostructures: Femtonewton Force Sensing and UltraSensitiveSpectroscopy" ORAL Marta Marín Suárez del Toro (University of Granada - Spain) Parallel Sessions NanoBiotechnology / Nanomedicine "Electrophoretic deposition to develop new optical sensing materials: application to a wireless oxygen sensing microrobot"

Manuel Marqués (UAM - Spain) Nanophotonics/ NanOptics/Plasmonics

KEYNOTE Parallel Sessions

"Plasmonic Nanoparticle Chain in a Light Field: A Resonant Optical Sail" Elena Martinez (IBEC - Spain) NanoBiotechnology / Nanomedicine

ORAL Parallel Sessions

"Cell behavior by the controlled immobilization of biotinylated proteins in a gradient fashion: non-linear concentration effects produced by unnoticed ligand nanoclustering" Ramón Martinez Máñez (UPV, Spain) NanoChemistry

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KEYNOTE Parallel Sessions

"Gated Materials in Delivery Applications" ORAl Amaia Martínez Muro (nanoBasque - Spain) Plenary Sessions Scientific Policy and Infrastructure "NanoBasque Strategy: Basque Country´s strategic bid for nanoscience, micro and nanotechnologies"

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Pilar Merino (Grupo Antolín, Spain) Industrial - Nanotechnology for Automotion applications

KEYNOTE Parallel Sessions

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Miguel Monge (Universidad de La Rioja - Spain) NanoChemistry

ORAl Plenary Sessions

Rosa Menéndez (INCAR-CSIC - Spain) Graphene "Preparation of graphenic materials of different structure"

"Synthesis of gold, silver and gold-silver nanostructures from organometallic precursors, plasmonic, bactericidal and catalytic properties." Mauricio Morais de Lima (Materials Science Institute - Spain) NanoMaterials

ORAl Plenary Sessions

"Low temperature optical emission of WZ InAs NWs" Eden Morales-Narváez (Catalan Institute of Nanotechnology - Spain) Graphene "Optical biosensors based on graphene"

ORAL Parallel Sessions

ORAL Enrique Navarro (Instituto Pirenaico de Ecología (CSIC) - Spain) Parallel Sessions Nanotoxicology and Nanosafety "Assessing ionic silver availability to algae from differently coated silver nanoparticles"

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Page Fernando Palacio (Instituto de Ciencia de Materiales de Aragón - Spain) NanoMaterials "Thermometry: a novel functionality for magnetic nanoparticles"

ORAL Plenary Sessions

Quentin Pankhurst (The Royal Institution of Great Britain, UK)

INVITED Plenary Sessions

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INVITED Plenary Sessions

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"Translational R&D in Healthcare Biomagnetics" Nacho Pascual (Freie Universitat Berlin, Germany)

"Sensing elementary processes in a molecular junction through force and light spectroscopy" Gian Bartolo Picotto (Istituto Nazionale di Ricerca Metrologica (INRIM), Italy)

INVITED Plenary Sessions

"Tools and Metrology at the nanoscale"

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ORAL José Manuel Pingarrón (Universidad Complutense de Madrid - Spain) Plenary Sessions NanoChemistry "Functionalization of electrode surfaces with three-dimensional networks of electropolymerized gold nanoparticles for biosensor design"

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ORAL Constança Porredon Guarch (Parc Científic de Barcelona - Spain) Parallel Sessions Nanotoxicology and Nanosafety "Need for guidelines specifically adapted for the toxicity testing of nanomaterials"

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ORAL Yury Rakovich (Centro de Fisica de Materiales (CSIC-UPV/EHU) - Spain) Plenary Sessions Nanophotonics/NanOptics/Plasmonics "Optical enhancement effect in metal-organic nanohybrids integrated with whispering-galerymode microcavities"

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ORAL Aritz Retolaza (TEKNIKER-IK4 - Spain) Plenary Sessions Nanophotonics/ NanOptics/ Plasmonics "Efficient organic distributed feedback lasers with active films imprinted by thermal nanoimprint lithography"

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Stephan Roche (ICN, Spain)

INVITED Plenary Sessions

"Transport Properties in Disordered Graphene: Effects of Atomic Hydrogen and Structural Defects" Ismael Rodea Palomares (Universidad Autónoma de Madrid - Spain) Nanotoxicology and Nanosafety "Assessment of nanoceria toxicity in aquatic photosynthetic organisms"

ORAL Parallel Session

ORAL Celia Rogero (Centro de Física de Materiales (CSIC-UPC/EHU) - Spain) Parallel Sessions NanoChemistry "Intermolecular H-Bonding for Porphyrin Molecules on Surfaces: experimental evidences and theoretical investigation."

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Claudio Sánchez Acevedo (TECNAN - Spain) Industrial - Nanotechnology for Automotion applications

KEYNOTE Parallel Sessions

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José A. Sánchez-Gil (Instituto de Estructura de la Materia (CSIC), Spain) Nanophotonics/NanOptics/Plasmonics "Single nanoparticle Plasmonics: Shape matters"

KEYNOTE Parallel Sessions

Miguel Roncales (AlphaSIP - Spain) NanoBiotechnology / Nanomedicine "Nanotechnology in the hemostasis laboratory"

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Page ORAL Juan Marcos Sanz Casado (Universidad de Cantabria - Spain) Plenary Sessions Nanophotonics/NanOptics/Plasmonics "Light Depolarization in Nanosphere-Dimers by Incoherent Mixing of Mueller Matrices"

Vyacheslav Silkin (Donostia Int. Physics Center - Spain) Graphene

ORAL Plenary Session

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KEYNOTE Parallel Sessions

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"Electronic Structure of Graphene" Bartolomé Simonet (SINATEC, Spain) Industrial - Nanotechnology for Automotion applications

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Robert Stokes (Nano Fabrication Systems Division - UK) ORAL Plenary Sessions NanoBiotechnology / Nanomedicine "Life science at the sharp end: recent developments in tip-based nanolithography in sensing, cell biology and diagnostics"

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Nikolay Usov (Universidad del País Vasco (UPV/EHU) - Spain) Nanomagnetism "Dynamics of magnetic nanoparticle with cubic anisotropy in a viscous liquid"

ORAL Plenary Sessions

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Renaud Vallée (Centre de Recherche Paul Pascal (CNRS), France) CNano GSO / TRAIN2 "Colloidal architectures for plasmonics"

KEYNOTE Plenary Sessions

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Jaume Veciana (ICMAB - Spain) NanoChemistry

ORAL Plenary Sessions

"Soft organic thin films, based on nanostructured polymeric composites, as ultra sensitive piezoresistive sensors for biomedical applications" Nora Ventosa (ICMAB - Spain) NanoChemistry

ORAL Parallel Session

"Compressed fluids: unique media for preparing vesicles with high structural homogeneity" Juan Carlos Vidal (Universidad de Zaragoza - Spain) ORAL Parallel Sessions NanoBiotechnology / Nanomedicine "An electrochemical competitive biosensor for fumonisin B1 (FB1) based on a DNA" Juan José Vilatela (IMDEA Materials - Spain) Nanotubes

"Synthesis and Characterization of Graphene"

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KEYNOTE Parallel Sessions

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"Functional nanomaterials inspired in coordination polymers" Amaia Zurutuza (Graphenea - Spain) Graphene

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ORAL Plenary Sessions

"Multifunctional Composites Based on Nanocarbons" Félix Zamora (Universidad Autónoma de Madrid, Spain) NanoChemistry

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Invited Speakers Plenary Session

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Latest advances in nanostenciling Jürgen Brugger, Veronica Savu Ecole Polytechnique Fédérale de Lausanne, Microsystems Laboratory, 1015 Lausanne, Switzerland Juergen.brugger@epfl.ch

Three-dimensional (3D) and organic electronics, plasmonic sensors, and some niche applications have recently demonstrated that stencil lithography (SL) is a reliable contender for parallel, resist-free, lowtemperature nanopatterning. The sub-100 nm minimum stencil aperture size can be translated into highresolution patterns across full 100 mm wafers. Organic and non-organic materials can be evaporated through the stencil on a variety of substrates. Stencils can be used as masks not only for deposition, but also for etching through or ion implantation. Enhancing the reliability and performance of SL at sub 100 nm scale is actively pursued. The main bottleneck for improving uniformity across large patterned areas with a standard stencil is the gap between stencil and substrate. For example, a gap varying between 5-30 μm across a 100 mm wafer, which is the average value for mechanically clamped stencil and substrate, can result in a loss of pattern resolution varying between 50 to 300 nm. Recent research demonstrated that by using membranes that comply with the wafer curvature/topography, the pattern distortion decreases by up to 95% [1]. In standard SL, the deposited pattern aspect ratio is limited to about 1:1. The material is deposited both on the substrate and on the stencil apertures sidewalls, leading to a gradual stencil clogging. A novel approach uses an integrated local heater which prevents the material accumulation around the apertures during the evaporation. In dynamic SL, where the stencil moves relative to the substrate during the patterning process, the heated stencil can now be continuously used in-situ for longer periods of time, opening avenues to new applications [2]. Efficient nanopatterning on 3D substrates is still a challenge. E-beam lithography, e.g., is limited by the possibility to spin a uniform thin film of resist across the sample. SL was successfully used to evaporate catalysts through nanoapertures on top of a 100 mm wafer of semi-released cantilevers [3]. The catalysts were used to grow silicon nanowires or carbon nanotubes at the apex of the cantilevers, providing thus ideal scanning probes for atomic force microscopy of high aspect ratio structures at the sub-micrometer scale. Label-free biosensing of molecules using localized plasmon resonance in metallic nanostructures has high sensitivity and is stable. In order to be cost-efficient, high through-put and versatile nanopatterning techniques are investigated. Here too, SL proved its potential as a resist-free technique with patterning capabilities down to 50 nm [4]. Stencil lithography at the sub-micrometer scale is proving thus a leading emerging technology for new applications in sensing, metrology, and electronics. References [1] [2] [3] [4]

K. Sidler et al., Nanoscale 4 (2012). V. Savu, S. Xie, and J. Brugger, Nanoscale 3, 2739 (2011). D. S. Engstrom et al., Nano Lett. 11, 1568 (2011). O. Vazquez-Mena et al., ACS Nano 5, 844 (2010).

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Figures

Figure 1: Compliant membranes improve resolution in stencil lithography: left) images of compliant membranes that reduce the stencil-substrate gap, and right) pattern distortion eliminated by the use of compliant membranes on flat Si substrates [1].

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Figure 2: Silicon nanowire (Si NW) and carbon nanotube scanning probes grown from catalysts deposited through nanostencil on semi-released cantilevers: left) fabrication schematic, center) Si NW probes, and right) comparison of AFM scans [3].

Figure 3: Plasmonic arrays fabricated with nanostencil: left) SEM images of stencils and resulting structures on Si substrate, center) extinction spectra of 100 nm size nanodots as a function of spacing, and right) resonance wavelength behavior with nanodot spacing [4].


Ultraviolet Nanoplasmonics: Materials and Applications Henry O. Everitt 1,2,3, Yang Yang,2 John Callahan,4 Pae C Wu,3 John Foreman,1 Arup Neogi,5 Tong-Ho Kim,3 April Brown,3 Gorden Videen,6 Pablo Albella,7 Borja Garcia-Cueto,7Francisco Gonzalez Fernandez,7 Fernando Moreno7 1

U.S. Army Aviation & Missile RD&E Center, Redstone Arsenal, AL USA 2 Department of Physics, Duke University, Durham NC USA 3 Department of Electrical and Computer Engineering, Duke University, Durham NC USA 4 AEgis Technologies Group, Inc., Huntsville, AL USA 5 Department of Physics, University of North Texas, Denton TX USA 6 U.S. Army Research Laboratory, Adelphi, MD USA 7 Grupo de O cada, Universidad de Cantabria, Santander, ESP

The last decade has seen an explosion in the development and exploitation of nanometer scale(subwavelength) metallic structures because of their remarkable plasmonic ability to enhance local electromagnetic fields.[1-7] Plasmonic research and applications based on silver or gold nanostructures are rapidly maturing at visible and near infrared wavelengths. The degree of enhancement depends strongly on two principal characteristics: the conductivity and size of the nanostructure. Silver has been widely used for visible or near-infrared wavelength applications because of its very high electron density. Gold is a popular alternative, in spite of its lower conductivity and greater interband absorption, because it does not oxidize as rapidly as silver. Although ultraviolet (UV) plasmonics is still in its infancy, opportunities abound for applying plasmonic techniques in the UV region: Raman scattering cross sections are dramatically higher, spontaneous emission rates are much faster, photocatalytic processes are currently inefficient, and improved electron photoemission sources are possible. For example, the Raman scattering intensity for excitation frequency f scales as f4, so Raman spectra taken at ~250 nm will be 81 –256 times stronger than spectra taken at the traditional wavelengths of 750 – 1000 nm. To explore these opportunities, the ideal UV plasmonic material must be identified. Although the plasmonic properties of aluminum (Al) and gallium (Ga) nanoparticles (NPs) are potentially as compelling in the UV as the respective properties of silver (Ag) and gold (Au) in the visible, there has been surprisingly little research into Al or Ga nanoplasmonics. This presentation will explore the potential of Al and Ga NPs for UV plasmonic applications. We have investigated the growth kinetics of Al and Ga NPs synthesized by molecular beam epitaxy (MBE) and demonstrated that significant UV local field enhancements are possible with Ga NPs.[8-12] Because of its low melting point (30°C), Ga forms a close-packed array of smooth hemispherical NPs when fabricated by room temperature MBE. The arrays exhibit remarkable long-term stability because of the rapid formation of a monolayer-thick, self-terminating oxide layer. By contrast, Al has a higher electron density with a bulk plasmon resonance deeper into the UV. However, its thick native oxide (Al2O3) diminishes its plasmonic properties: the local field enhancement falls exponentially with plasmon - emitter/analyte separation. Specific applications to be discussed include enhanced or suppressed spontaneous emission and surfaceenhanced Raman spectroscopy of nearby emitters and analytes, respectively. Excitonic mission rates from a quantum well emitter have been accelerated by a factor of 92 through resonant coupling to a nearby surface plasmon (Fig. 1),[13] while spatially averaged Raman signals from cresyl violet have been amplified in the visible and UV by nearby Ga NPs (Fig. 2).[12] A theoretical analysis using the discrete dipole approximation reveals how the plasmon resonance shifts polarimetrically as a function of NP size and shape (Fig. 3).[14]

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References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]

W. Barnes, J. Lightwave Tech. 17 (1999) 2170–2182. C. Haynes and R. van Duyne, J. Phys. Chem. B 105 (2001) 5599–5611. J. Jackson and N. Halas, Proc. Natl. Acad. Sci. U. S. A. 101 (2004) 17930–17935. K. Kneipp, Phys. Today 60, 40–46 (2007). S. Lal, N. K. Grady, J. Kundu, C. S. Levin, J. B. Lassiter, and N. J. Halas, Chem. Soc. Rev. 37 (2008) 898–911. J. Vuckovic, M. Loncar, and A. Scherer, IEEE J. Quantum. Electron. 36 (2000) 1131–1144. Z. Wang, S. Pan, T. Krauss, H. Du, and L. Rothberg, Proc. Natl. Acad. Sci. U. S. A. 100 (2003) 8638–8643. S. Choi, T.-H. Kim, A. S. Brown, H. O. Everitt, M. Losurdo, G. Bruno, and A. Moto, Appl. Phys. Lett. 89 (2006) 181915. S. Choi, T.-H. Kim, H. O. Everitt, A. Brown, M. Losurdo, G. Bruno, and A. Moto, J. Vac. Sci. Tech. B 25 (2007) 969. S. Choi, T.-H. Kim, P. C. Wu, A. S. Brown, H. O. Everitt, M. Losurdo, and G. Bruno, J. Vac. Sci. Tech. B 27 (2009) 107–112. P. C. Wu, T.-H. Kim, A. S. Brown, M. Losurdo, G. Bruno, and H. O. Everitt, Appl. Phys. Lett. 90 (2007) 103119. P. C. Wu, C. G. Khoury, T.-H. Kim, Y. Yang, M. Losurdo, G. V. Bianco, T. Vo-Dinh, A. S. Brown, and H. O. Everitt, J. Am. Chem. Soc. 131 (2009) 12032–12033. A. Neogi, C. Lee, H. Everitt, T. Kuroda, A. Tackeuchi, and E. Yablonovitch, Phys. Rev. B 66 (2002) 153305. P. Albella, B. Garcia-Cueto, F. Gonzalez, F. Moreno, P. C Wu, T.H. Kim, A.S. Brown, Y. Yang, H. O. Everitt, and G. Videen, NanoLetters 11 (2011) 3531-3537.

Figures

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Figure 1: a) TRPL spectra of the InGaN QW emission into free space and altered by the nearby silver plasmon. b) The Purcell enhancement factor of the emission rate as a function of emission energy, showing that the enhancement is greatest when the emission is resonant with the LSPR at 2.85 eV.

Figure 2: Demonstration of UV SERS of CV by Ga NPs on a sapphire substrate, compared to the Raman signal of CV on bare sapphire for laser energies red of (1.95 eV), resonant with (3.8 eV), and blue of (4.5 eV) the plasmon resonance.

Figure 3: Absorption efficiencies as a function of incidence angle α for a hemispherical Ga NP having a 20 nm radius on a plane sapphire substrate and illuminated by S-polarized (solid lines) or P-polarized (dashed lines) Gaussian beams. Inset shows a scanning electron microscope of Ga NPs deposited by MBE.


Wide band gap nanowires for LED applications Guy Feuillet CEA-LETI, Optics and Photonics Dpt, Grenoble, France

Wide band gap semiconductors such as III- nitrides or II-oxides are materials of choice for blue to near UV LEDs applications, in particular for solid state lighting. Resorting to nanowires NWs of these materials opens up news possibilities in terms of device design, related for instance to their high surface/volume ratio, or to the natural and easy light extraction efficiency. It is also speculated that doping difficulties, e.g. p type doping in ZnO, might be circumvented because of the low dimensionality of these nanostructures. After describing the issues related to solid state lighting, and how the use of NW LEDs might overpass these limitations, we will first present the state of the research on the subject. This will be followed by a description of some of our work at CEA/LETI, based on the use of either ZnO or GaN nanowires. For MOVPE grown ZnO NWs, we could recently demonstrate the growth of core-shell ZnO / ZnMgO quantum well hetero-structures (Cf. figure 1) with a high room T° quantum efficiency of more than 50%. Interestingly, by varying the Mg concentration in the barriers of the core-shell heterostructures, it was possible to assess for the first time the plastic relaxation processes in these one-dimensional structures and to show that the optical efficiencies are clearly related to the absence of extended defects in the 1D radial structures. Selected area growth of ZnO NWs was also achieved on pre-patterned sapphire substrates opening the way to a better control of these radial heterostructures. As for GaN NW based LEDs, we used MBE to devise axial p-n multiple InGaN / GaN quantum well heterostructures on n type silicon substrates. Thanks to the coalescence of the p-type Mg doped top region of the NWs grown at low temperature, some self-planarization can be achieved, which makes the LED technological integration much easier. The optimisation of the structure, for instance through the use of an electron blocking layer, led to clear blue to red emission under electrical injection, the emission wavelength depending on the indium concentration in the barrier. Local characterization was carried out through the use of combined electro- and photo-luminescence (EL , PL) in a confocal microscope, which allowed us to differentiate between material and electrical problems as the cause of non uniformities of the emission. As in the case of 2D LEDs, the observed blue-shift of the emission with increasing injected current is the signature of quantum confined Stark effect (QCSE). To deal with this detrimental effect which is associated to the non centro-symmetry of the hexagonal material, one solution relies in using radial heterostructures - so call core-shell - : in this case , the quantum wells are grown along non polar surfaces ( the side facets of the nanowire). Up to now, the growth of core –shell NWs can only be achieved by using MOVPE growth processes. The LED NW heterostructure consists of an n-type GaN:Si core radially covered by InGaN/GaN quantum wells and a p-type GaN:Mg outer shell, the whole structure being grown onto 2 inch doped silicon. Micro PL and cathodo-luminescence revealed that there was no blue shift of the radial well emission wavelength with increasing injection current, clearly indicating the absence of any quantum confined stark effect. Room temperature continuous-wave electrical injection through the Si substrate is successfully demonstrated, producing blue electroluminescence at 450 nm in this vertically integrated 1cm²-chip nanowire LED.

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Figures

Axial growth

Radial growth

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Figure 1 : STEM micrographs of a ZnO based core-shell nanowire

Figure 2: Electroluminescence of GaN based core-shell nanowires


Translational research in Nanomedicine: 30 years of clinical practice, the Science, the regulatory path and the challenges Rogério Gaspar Faculty of Pharmacy University of Lisbon and iMed.UL Research Center (Portugal); rgaspar@ff.ul.pt

Nanomaterials intended for clinical use have to be evaluated under very strict requirements existing for all clinical products. Within different regulatory frames the most strict is certainly the one devoted to medicinal products. During the last three decades of clinical experience, more than 40 products were given final approval for clinical routine use and hundreds given partial authorization under the approval of specific clinical trials in different stages (Phase I, II or III). The requirements for clinical use (under clinical trials or in final marketing authorization) are known and have been tested against different technologies and materials. It’s a very good example of how an existing regulatory frame can incorporate technological innovation and deliver adequate scientific appraisal preserving patients/populations safety, incorporating risk management approaches. The toxicity/immunotoxicity of the product as a whole and all the components (they may ultimately be released by degradation/metabolism) must be considered in the context of the proposed route of administration from the beginning. A recent statement “interestingly pharmaceutical sciences are using nanoparticles to reduce toxicity and side effects of drugs and up to recently did not realize that carrier systems themselves may impose risks to the patient” was not a well-informed observation. Over many decades, pharmaceutical scientists from academia and industry have studied the general toxicity, hematocompatibility, complement activation, immunotoxicology, pharmacokinetics, toxicokinetics, and metabolic fate of novel materials proposed for use as components of advanced drug delivery systems. Moreover all the nanomedicine products entering clinical development must be subjected to rigorous, often “good laboratory practice” (GLP), preclinical evaluation. There are important points to make in relation to the complex, novel, and often hybrid nanomedicines emerging now. Some researchers often claim that their material or technology is “biocompatible” or “biodegradable” without any robust scientific experimentation (in vitro or in vivo) to back their statement. (In the context of a medicinal product rather than a biomaterial the term“toxicity” is more appropriate than “biocompatibility” as they have different meanings). Cytotoxicity studies often use short time frames (hours) chosen to match in vitro pharmacological experiments without any consideration of likely clinical pharmacokinetics (patient exposure can be hours, days, or months), and the concentration range used is too low to define an inhibitory concentration for 50% cell kill (IC50). Such statements promote dogma that pervades the literature. Claims of biodegradation are rarely qualified by time frame or the mechanism. Many natural polymers, e.g., alginates, chitosans, dextran, are poorly degraded by mammalian enzymes, and many materials actually never access the physiological compartment (maybe intracellular) where the target mammalian catabolic machinery resides. Additionally, chemical functionalization can render a natural polymer effectively nonbiodegradable. Misuse of the terms “biocompatibility” and toxicity is also exemplified by the frequent misuse of the term GRAS (generally recognized as safe). The FDA term GRAS is a designation given to a specific material (designated specification), for use at specific doses and via designated routes of administration. There is frequently failure to realize that materials approved for topical or oral administration maybe entirely unsuitable for parenteral use. Techniques used to evaluate nanomedicine safety continue to evolve. Screening often uses in vitro cytotoxicity testing (e.g., polymers, dendrimers and polymeric nanoparticles) to give an early indication of

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the material suitability for a particular use. Microscopy (TEM/SEM and light) is also used to highlight subtle cellular changes, but such techniques require careful interpretation as sometimes methodology used can introduce artifacts (“seeing is not always believing”). It has been noted that when synthetic polymers and nanomaterials are administered together with noncovalently or covalently conjugated cytotoxic agents, DNA, or antigens, they can markedly alter genetically controlled responses, and this has given rise to studies designed to explore polymer genomics. To note, for useful data to come from biological assays, nanomaterials must be reproducibly manufactured and well characterized. Putative parenteral nanomedicines displaying acceptable toxicity in vitro must then be subjected to rigorous investigation of their antigenicity, immunotoxicity, and potential to activate complement. Development of specific in vitro assays that can be validated for nanomaterials is to be applauded, but the establishment of meaningful high-throughput screening, especially in the context of safety evaluation that can be optimal for all nanomaterials, is not without challenges. For each nanomedicine it is essential to choose a specific portfolio of tests and the assays used must be carefully optimized, for example by (i) using time frames that are relevant to material’s pharmacokinetics (single time point readouts can easily give false positive or false negative results), (ii) using the cell lines to which the material will most likely be exposed (primary cells may be needed, and all cells in vivo will be exposed to serum), and (iii) using analytical techniques only where it is known that the analyte does not interfere with the assay readout. All nanomedicines must display an acceptable risk_benefit with respect to proposed use, and early safety studies should be used as a stop_go checkpoint to decide whether or not the technology has promise for further development toward clinical trials in the context of the proposed use.

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Current developments in the research landscape of nanomedicines brought the attention to the fact that as an already well established area of clinical practice, it now faces also some questions previously addressed by new chemical entities and biologicals. The current regulatory path has to be perceived in order to understand exactly the implications coming from the legislative and regulatory European frame. We will discuss the issues bringing together the regulatory path and the underlying Science.

Bibliography (1) Gaspar, R (2007), Regulatory issues surrounding nanomedicines: setting the scene for the next generation of nanopharmaceuticals, Nanomedicine 2(2), 143-147 , DOI 10.2217/17435889.2.2.143 (2) Gaspar, R. and Duncan, R. (2009) Polymeric carriers: preclinical safety and the regulatory implications for design and development of polymer therapeutics. In: Vicent, M. J. and Duncan, R. (Eds. Theme Issue: Polymer Therapeutics: Clinical Applications and Challenges for Development), Advanced Drug Delivery Reviews 61, 1220-1231, DOI: 10.1016/j.addr.2009.06.003 (3) Gaspar, R. (2010) Therapeutic Products: Regulating Drugs and Medical Devices. Chapter 14 in International Handbook On Regulating Nanotechnologies edited by Graeme A. Hodge, Diana M. Bowman and Andrew D. Maynard. 640 pp, ISBN 978 1 84844 673 1 (4) Duncan, R. and Gaspar, R. (2011), Nanomedicine(s) under the microscope, Molecular Pharmaceutics, 8 (6), 2101–2141, DOI: 10.1021/mp200394t


Potential Applications for Graphene Devices in Nanoelectronics Max C. Lemme KTH Royal Institute of Technology, Isafjordsgatan 22, Electrum 229, 16440 Kista, Sweden lemme@kth.se

While benchmarking figures for graphene show remarkable properties like ballistic conductance over several hundred nanometers or charge carrier mobilities of several 100.000 cm2/Vs, integrated graphene devices are limited by defects in graphene and its dielectric environment. Furthermore, the lack of a band gap limits the applicability of graphene field effect transistors (GFETs) for logic applications. This talk will compare the expected RF performance of realistic GFETs with current silicon CMOS technology. In particular, a systematic model-based comparison of RF performance metrics between 65nm GFETs and silicon MOSFETs was performed. We show that GFETs slightly lag behind in fT and require at least a carrier mobility of Ο = 3000 cm2/Vs in order to achieve similar RF performance. While a strongly nonlinear voltage-dependent gate capacitance inherently limits performance, other parasitics such as contact resistance are expected to be optimized as GFET process technology improves. Finally, we quantify the Ο values, which would allow future GFETs to match and exceed CMOS, potentially up to THz operation. In addition, a novel graphene-based hot electron transistor will be introduced: the graphene-base transistor (GBT) [2]. The GBT combines the concept of hot electron transistors with the unique properties of graphene to potentially overcome the difficulties faced by graphene RF FETs, such as the very high off current (Ioff) and the lack of current saturation. Instead of the lateral transport along the graphene in the GFET, the GBT concept is based on a vertical arrangement of emitter, base, and collector, just like a hot electron transistor or .recently suggested graphene tunnel FETs [3]. In the off-state, charge carriers face a dielectric barrier. In the on-state, the emitter-base diode injects hot electrons across the base (here: graphene) into the conducting band of the insulator separating the base from the collector (base-collector insulator, BCI). Electrons leave the emitter by Fowler–Nordheim quantum tunnelling through the emiterbase insulator (EBI). In the GBT, graphene acts as the control electrode (similar to the grid in a vacuum tube). In contrast to ultrathin metal films, graphene is far superior, because it has no pinholes, which leads to very low resistivity, while its monatomic thickness guarantees ballistic transport across the base. This, in turn, results in a high gain, low base resistance, and low base current. In addition, the GBT allows minimizing Ioff by proper BCI design and shows current saturation when the output voltage exceeds the value necessary to remove the tunneling barrier in the ballistic transport across the BCI. With the right choice of materials and device geometry, we conclude that the GBT should be capable of THz operation. The GBT may also have potential for logic integration. Finally, graphene is an optoelectronic material and its application as a broadband photodetector will be discussed [4]. By tuning both single-layer and bilayer gated graphene devices from bipolar to unipolar, we demonstrate a gate-activated photoresponse. Our results can be explained with a model of the photothermal effect, where elevated temperatures at the p-n-junction induce thermoelectric currents. We anticipate that the responsivity can be further increased by converting incoming light more efficiently by integration with metallic plasmonic structures or by reducing the device size, using transparent top gates, and by optimizing device technology to enable p-n devices in the ballistic regime. With the possible extension into far-IR / terahertz radiation and the high conductivity of graphene, we envision broad band bolometers with submicrometer pixilation.

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References [1] [2] [3]

[4]

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S. Rodriguez et al., "RF Performance Projections of Graphene FETs vs. Silicon MOSFETs", arXiv:1110.0978v1, (2011). W. Mehr et al., "Vertical Transistor with a Graphene Base", arXiv:1112.4520v1., (2011). L. Britnell, R.V. Gorbachev, R. Jalil, B.D. Belle, F. Schedin, A. Mishchenko, T. Georgiou, M.I. Katsnelson, L. Eaves, S. V. Morozov, N.M.R. Peres, J. Leist, A.K. Geim, K.S. Novoselov, L.A. Ponomarenko, "Field-Effect Tunneling Transistor Based on Vertical Graphene Heterostructures," Science, February 2, (2012). M.C. Lemme et al. "Gate-Activated Photoresponse in a Graphene p n Junction", Nano Lett., 11, (2011), 4134.


Optical Trapping of Nanostructures: Femtonewton Force Sensing and Ultra-Sensitive Spectroscopy Onofrio M. Maragò CNR-IPCF, Istituto per i Processi Chimico-Fisici, V.le F. Stagno D’Alcontres 37, Messina, Italy marago@me.cnr.it

Abstract Optical trapping[1-3] (OT) of nanostructures [3-16] have acquired tremendous momentum in the last few years. Manipulating nanoparticles with standard OT is generally difficult because radiation forces scale approximately with particle volume [1-3,6,8] and thermal fluctuations easily overwhelm trapping forces at the nanoscale. However carbon nanotubes, [4,5,7] (Fig. 1) graphene,[9] (Fig. 2) polymer nanofibers,[6,10] plasmonic nanoparticles,[11,12] and semiconductor nanowires,[6,13,15,16] (Fig. 3) have been stably trapped thanks either to their highly anisotropic geometry [4-7,10,13,15,16] or to their intrinsic resonant behavior. [7,8,11,12] Nanostructures have been trapped and manipulated to build nano-assemblies,[15,16] used as probes for light-driven rotations,[7] as well as accurately measure forces with resolution at the level of few femtonewtons crucial for photonic force microscopy applications[3,5,13] combining the outstanding forcesensing capabilities of OT with increased nanometric precision and bridge the gap between micro and nanoscale in fluidic environments (Fig. 1 & 4). Furthermore the integration of OT with Raman and SERS spectroscopy (Fig. 2 & 3) allowed for ultrasensitive chemical-physical analysis of trapped nanoparticles.[9,12,14] In this context the role of shape[5,6,9,10] and size-scaling[13] is crucial for understanding the interplay between optical forces and hydrodynamic interactions[17] that change dramatically with size, hence much affecting both forcesensing and spatial resolution in precision applications (Fig. 3).[3,5] In conclusion, optical trapping of nanostructures offers a unique opportunity to trap, manipulate, probe, characterize, individual nanostructures with well defined optical, mechanical, thermal properties. The range of applications is huge and spans from photonic force microscopy with femtonewton resolution, Raman and SERS spectroscopy in liquid, to novel approaches in laser cooling, quantum optics, and ion trapping.[18-20] References [1]

A. Ashkin, J. M. Dziedzic, J. E. Bjorkholm, S. Chu. Opt. Lett., 11 (1986) 288; See also Special Issue in Nature Photon., 5, Issue 6 (2011). [2] F. Borghese, P. Denti, R. Saija, M. A. Iatì. Opt. Express, 15 (2007) 11984. [3] O. M. Maragò, P. H. Jones, P. G. Gucciardi, “Photonic Force Microscopy: From Femtonewton Force Sensing to Ultrasensitive Spectroscopy”, in Scanning Probe Microsc. in Nanoscience & Nanotech.; B. Bushan Ed.; Springer-Verlag: Berlin (2010). [4] O. M. Maragò, et al. Physica E, 8 (2008) 2347. [5] O. M. Maragò, et al. Nano Lett., 8 (2008) 3211. [6] F. Borghese, et al. Phys. Rev. Lett., 100 (2008), 163903. [7] P. H. Jones, et al. ACS Nano, 3 (2009) 3077. [8] R. Saija R., et al. Opt. Express, 17 (2009) 10231. [9] O. M. Maragò, et al., ACS Nano, 4 (2010) 7515. [10] A. A. R. Neves, et al., Opt. Express, 18 (2010) 822. [11] E. Messina, et al. ACS Nano, 5 (2011) 905.

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[12] [13] [14] [15] [16] [17] [18] [19] [20]

E. Messina, et al. J. Phys. Chem C, 115 (2011) 5115. A. Irrera, et al. Nano Lett., 11 (2011) 4879. M. G. Donato, et al. Nanotechnology, 22 (2011), 505704. R. Agarwal, et al. Opt. Express 13 (2005) 8906. P. J. Pauzauskie, et al. Nat. Mater. 5 (2006) 97. R. Di Leonardo, et al. Phys. Rev. Lett. 107 (2011) 044501. A. Ridolfo, et al. ACS Nano 5 (2011) 7354. P. F. Barker, M. N. Shneider, Phys. Rev. A, 81 (2010) 023826. O. Romero-Isart, A. C. Pflanzer,M. L. Juan, R. Quidant, N. Kiesel, M. Aspelmeyer, J. I. Cirac. Phys. Rev. A, 83 (2011) 013803. [21] B. E. Kane, Phys. Rev. B, 82 (2010) 115441. Figures

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Figure 1: Optical trapping of nanotubes. (a) Optical trapping geometry. (b) Image of a trapped nanotube bundle oriented by radiation torque along the optical axis. (c) Image of the same bundle un-trapped (laser is off) and randomly oriented by Brownian motion. (d) Tracking of a trapped nanotube bundle Brownian motion. The calibration of the trap allows force sensing with femtonewton resolution in liquid environment.

Figure 2: Optical trapping of graphene. (a) Sketch of the Raman Tweezers setup. Trapping and excitation is performed with the same laser beam at 633nm. Collection of the Raman signal is guided through the same objective used for trapping. (b) Typical Raman spectrum for single layered graphene in the optical trap.

Figure 3: Optical trapping of plasmonic nanoaggregates and SERS.[8,11,12] (from left to right) Sketch of the laser ablation set-up and SEM image of the plasmonic nanoaggregates with controlled optical properties. Sketch of the SERS optical tweezers: a nanoaggregate is held within the trapped while a SERS spectrum is collected with the same optics.

Figure 4: Size-scaling in the optical forces on Silicon nanowires.[6,13] (from left to right) SEM image of the Silicon nanowires with length in the range 1-5 Îźm and diameter 10 nm. Geometry. Transverse Root-MeanSquared-Displacement as a function of nanowire length and Brownian motion in the trap.


Translational R&D in Healthcare Biomagnetics Quentin Pankhurst Institute of Biomedical Engineering, University College London, Gower Street, London WC1E 6BT q.pankhurst@ucl.ac.uk

‘Healthcare Biomagnetics’ – the sensing, moving and heating of magnetic nanoparticles in vitro or in the human body – is a rapidly changing field that is attracting a great deal of interest worldwide.[1] It offers the potential to develop safe and convenient alternatives for a diverse range of therapeutic and diagnostic healthcare applications, using injectable materials of proven safety and reliability. In doing so, it makes use of the three fundamental ‘action-at-a-distance’ properties of magnetic materials – their ability to act as remote sensors,[2] mechanical actuators,[3] and heat sources.[4] The versatility of the field is leading to the emergence of multi-modal applications, combining two or more of the sensing-moving-heating properties in the same product. Similarly, certain applications are now entering or are close to beginning Phase I/II clinical trials, or in the case of in vitro products, are already entering the marketplace. Pertinent examples of work in the fields of targeted delivery of drugs and other therapeutic agents, and others, will be presented and discussed. References [1] [2] [3] [4]

Q.A. Pankhurst et al.: J. Phys. D, 36, R167, (2003); Q.A. Pankhurst et al.: J. Phys. D, 42, 224001 (2009). U.A. Gunasekera et al.: Targeted Oncology, 4, 169 (2009); M.R. Loebinger et al.: Cancer Research, 69, 8862 (2009); K.L. Vigor et al.: Biomaterials, 31, 1307 (2010). E. Stride et al.: Ultrasound Med. Biol., 35, 861 (2009); J. Riegler et al.: Biomaterials, 31, 5366 (2010); J. Riegler et al.: J. Phys. D, 44, 055001 (2011). M. Kallumadil et al.: J. Magn. Magn. Mater., 321, 3650 (2009); L.A. Thomas et al.: J. Mat. Chem., 19, 6529 (2009); K. Parcell et al.: Thorax, 65, A41 (2010).

Figures

Figure 1: Representative images related to (from left to right): magnetic sensing, actuation and hyperthermia

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Sensing elementary processes in a molecular junction through force and light spectroscopy Jose Ignacio Pascual Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany

Tunnelling electrons in STM are ideal probes of electronic structure and excitations of surfaces and adsorbates. Combination of energy, space and time resolution is a powerful approach to track elementary processes involved in fields like chemistry, molecular electronics, magnetism,… However, the presence of a metal tip in the proximity of an individual molecule can go beyond electronics. Here, I will present two new approaches to molecular spectroscopy set-up recently in our laboratories at the FUBerlin: noncontact Force spectroscopy and light spectroscopy. These methods will be introduced with on-going experiments in our laboratory: −

While (electron-induced) light emission is a process mediated by field-enhanced plasmons at the tunnel junction, they also bring information about energy transitions involved in the tunnelling process through a nano-object. I will show how image states living at the surface of materials are active luminescent sources.

The measurement of forces at the atomic scale is done by attaching the STM tip to a stiff resonator. Interaction forces and energy can be sensed with high resolution. When investigating a molecular junction, the measurement of forces simultaneously to electrical transport, provides a new insight in molecular flexure, deformations and their relation to transport. I will present two examples: the formation of a weak bond between two molecules and the stretching of a molecular junction.

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Tools and Metrology at the nanoscale Gian Bartolo Picotto Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 73, 10135 Torino, Italy g.picotto@inrim.it

The continuous development of instrumentation and measurement techniques has opened up new insights in the knowledge of the property of matter and processes at the nanoscale. Innovative instrumentation plays a crucial role for measuring, manipulating and machining of material, including new measurement needs from the modern production of semiconductor and integrated devices [1]. Nanotechnology is now facing a growing demand of quantitative measurements and traceable standards to support the reliability, safety and competitiveness of products and services [2,3]. This requires the definition of protocols and methods to ensure the quality of measurements and traceability to standards, as well as the adoption of an agreed standardization framework supported by pre-normative research. Several projects have been carried out by national Metrology Institutes and other labs to extend traceability and to improve the measurement capabilities at the nanoscale. The achieved steps and consistency of measurements have been demonstrated by several inter-laboratory comparisons. This contribution aims to address tools, capabilities and standards in nanometrology, with emphasis on dimensional and surface measurements for characterization and design of materials, structures and devices, including linewidths, gratings, grids, step-height standards and particles. The state of the art of standards available for surface metrology is presented together with a few example of applications. A description of the instrument design and calibration of a metrological scanning force microscope is given. Measurement needs for precise positioning and control of tip/sample displacements are discussed together with recent achievements in high-resolution optical interferometry. Quantitative measurements rely on traceable standards, calibrated instruments and a consistent estimation of the uncertainty. A detailed description of the uncertainty budget as estimated in a case of study at the nanoscale is given.

References [1] [2] [3]

International Technology Roadmap for semiconductor – 2011 Edition – Metrology http://www.itrs.net/Links/2011ITRS/2011Chapters/2011Metrology.pdf. National Nanotechnology Initiative – Strategic Plan (2011) http://www.nano.gov/node/581 European Commission – Nanotechnology http://ec.europa.eu/nanotechnology/index_en.html

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Transport Properties in Disordered Graphene : Effects of Atomic Hydrogen and Structural Defects Stephan Roche Catalan Institute of Nanotechnology (ICN)-CIN2 Theoretical & Computational Nanoscience Group Email: stephan.roche@icn.cat Group webpage http://www.icn.cat/index.php/en/research/core-research/theoretical-and-computational-nanosience/overview

This talk will focus on the presentation of transport properties in graphene-based-materials, driven by chemical functionalization and structural defects. To circumvent the current hurdles preventing the advent of graphene nanoelectronics, it has become urgent to benefit from engineering complexity at the nanoscale and the unique potential of graphene as a bridging platform between top-down conventional CMOS technologies and (bio)-chemistry self-assembling processes. Here, by using state-of-the-art multiscale simulations (combining first-principles with tight-binding schemes), we present several electronic transport features in complex forms of chemically modified graphene based materials. Past examples include the use of boron or nitrogen-doped to produce graphene-based nanoribbons exhibiting “mobility gaps” of width as large as 1eV, providing an efficient switching behavior principle even in the presence of a vanishing electronic band-gap. The possibility to design a switching effect based on mechanical deformation of graphene nanoribbons. Here, we will explore the effect of atomic hydrogen driving intrinsic magnetic ordering will be presented from a theoretical perspective and in comparison with most recent experiments. It will be shown that the existence of a long range ferromagnetic state in weakly hydrogenated graphene could be related to a highly robust metallic state down to cryogenic temperatures, in contrast to the localization regime obtained in absence of ferromagnetic order. Additionally, the possibility to observe measurable magnetoresistance signals due to magnetism in graphene will be discussed. As a second issue, the presence of structural defects will be shown to yield conventional localization effects.

Related bibliography 1.

2.

3.

4.

Mark H. Rümmeli et al., Graphene: Piecing it Together, Advanced Materials, 23, 4471–4490 (2011) F. Ortmann, A. Cresti, G. Montambaux and S. Roche, Magnetoresistance in disordered graphene: The role of pseudospin and dimensionality effects unravelled, European Physics Letters, 94, 47006 (2011) D. Soriano, N. Leconte, P Ordejon, J.-Ch. Charlier, J.-J. Palacios, and S. Roche, Magnetoresistance and Magnetic Ordering Fingerprints in Hydrogenated Graphene, Physical Review Letters 107, 016602 (2011) Lherbier, S.M.M. Dubois, X. Declerck, Sr. Roche, Y.-M. Niquet and J.C. Charlier, Two-dimensional Graphene with Structural Defects: Elastic Mean Free Path, Minimum Conductivity and Anderson Physical Review Letters, 106, 046803 (2011) N. Leconte, D. Soriano, S. Roche, P. Ordejon, J.-Ch. Charlier, and J. J. Palacios Magnetism-Dependent Transport Phenomena in Hydrogenated Graphene: From Spin-Splitting to Localization Effects ACS Nano 5, 3987 (2011); DOI: 10.1021/nn200558d

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5.

Cresti, A. López-Bezanilla, P. Ordejón and S. Roche Oxygen surface functionalisation of graphene nanoribbons for transport gap engineering ACS Nano 5 (11), 9271–9277 (2011)

Figures

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Figure 1: Magnetoresistance of a weakly hydrogenated graphene sample predicted numerically.


Keynotes Speakers CNano GSO Session

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Peptide fibers: Electrospinning from solutions, molecular vibrational analysis Alexander M. Bittner, Wiwat Nuansing, Amaia Rebollo, JosĂŠ MarĂ­a Mercero CIC nanoGUNE, Av. Tolosa76, 20018 Donostia, Spain; Ikerbasque, 48011 Bilbao, Spain; University of the Basque Country (UPV-EHU), 20080 Donostia, Spain a.bittner@nanogune.eu

Besides their wide biochemical relevance, peptides can assemble to defined supramolecular structures such as fibers [1,2] and tubes [3-6]. Of these, amyloid-like fibers are of special medical relevance for deseases such as Alzheimer [1]. While the main driving mechanism is certainly based on electrostatics, the directing role of aromatic groups might be essential. We used short peptides and peptide derivates that contain the aromatic side groups fluorenyl and phenyl. Fibers can be built by growth in solution, or by electrospinning from concentrated solutions [7], which is normally only possible for macromolecules (Fig. 1). The choice of the solvents is here critical; fluorinated alcohols and acids are often required. We elucidated chemical groups in the fibers by Raman and infrared spectroscopy [8]. The observed spectra compare very well with simulation results of the respective single molecules in vacuum (Fig. 2), with the exception of zwitterions where a dielectric environment was modelled. We were able to assign all observed vibrations. The main differences between solid phases and single molecules are found for O-H and N-H stretching and bending vibrations, due to extensive hydrogen bonding in solids. While the fluorenyl and phenyl residues cause pi-stacking of the molecules, this barely manifests in the spectra, but clearly in the structures.

67 References [1] [2] [3] [4] [5] [6] [7] [8]

R. V. Ulijin, A. M. Smith, Chem. Soc. Rev. 37 (2008) 664. R. Fairma, K. S. Akerfeldt, Curr. Opin. Struct. Biol. 15 (2005 453. A. Mueller, F.J. Eber, C. Azucena, A. Petershans, A.M. Bittner, H. Gliemann, H. Jeske, C. Wege, ACS Nano 5 (2011) 4512. Z. Wu, A. Mueller, S. Degenhard, E. Ruff, F. Geiger, A.M. Bittner, C. Wege and C. Krill III, ACS Nano 8 (2010) 4531. A.M. Bittner, F. Heber, J. Hamaekers, Surf. Sci. 603 (2009) 1922. S. Balci, D.M. Leinberger, M. Knez, A.M. Bittner, F. Boes, A. Kadri, C. Wege, H. Jeske, K. Kern, Adv. Mater. 20 (2008) 2195. G. Singh, A.M. Bittner, S. Loscher, N. Malinowski, K. Kern, Adv. Mater. 20 (2008) 2332. W. Nuansing, A. Rebollo, J.M. Mercero, J. Zuniga, A.M. Bittner, J. Raman Spec. (2012), in revision.


Figures

Figure 1: Optical micrograph of Fmoc-Phe-Gly fiber, electrospun from HFIP (hexafluoroisopropanol). At right: Chemical structure of Fmoc-Phe-Gly.

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Figure 2: Vibrational spectra of Fmoc-Phe-Gly


Progress towards SWAP single molecule – A chemical approach Jacques Bonvoisin CEMES/CNRS GNS group, 29 rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4, France jbonvoisin@cemes.fr

Integrating a logical function in a single molecule should allow reaching the ultimate size of a material based calculator. Several concepts are now under development to make a calculation using a single molecule. [1] One of them is to divide the molecule into “qubits” in order to exploit the quantum engineering developed since several years around quantum computers. [2] The project developed here consists of synthesizing a molecule which would be able to realize a logical function such as an inversor (SWAP). This molecular logical gate with an optical reset would be made of an IN/OUT ruthenium(III) bimetallic centers. These two ruthenium(III) ions would be in magnetic interaction through bonds, via conjugated organic backbones, with a third ruthenium ion. The magnetic interaction is switched ON and OFF depending on the oxidation state of the central ruthenium atom which can be changed by light by using the special properties of mixed-valent system. Therefore the light will trigger the calculation by adding/removing an extra electron on the central ruthenium atom. The special feature of this target molecule constituted of four metallic centers is that coordination spheres around ruthenium atoms can be different by chosen substituents and then one can have optical access to selected ruthenium atoms. In this contribution, one will see which steps have been made towards the target molecule.[3] In particular, we will show some recent results on STM images concerning ruthenium complexes on gold surfaces. [4]

Figure 1: Experimental (top) and EHMOESQC calculated (bottom) STM image of Ru(dbm)3 adsorbed on Ag(111) surface at liquid helium temperature

References [1] [2] [3] [4]

C. Joachim, J.K. Gimzewski, A. Aviram, Nature, 2000, 408, J41 M. A. Nielsen, I. L. Chuang, Quantum computation & quantum information, Cambridge University Press 2000 a) S. Munery, J. Jaud , J. Bonvoisin. Inorg. Chem. Commun. 2008, 11, 975-977 b) C. Viala, J. Bonvoisin. Inorg. chim. Acta 2010, 363, 1409-1414 S. Munery, N. Ratel-Ramond, Y. Benjalal, L. Vernisse, O. Guillermet, X. Bouju, R. Coratger, J. Bonvoisin. Eur. J. Inorg. Chem. 2011, 2698–2705

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Measurement of Rheological Fluid Properties using MEMS I. Dufour1, A. Darwiche2, E. Lemaire1, B. Caillard1, Y. Amarouchene2, D. Saya3, C. Ayela1, H. Kellay2, F. Mathieu3, C. Pellet1, M. Guirardel4, A. Maali2, Liviu Nicu3, A. Colin4 1

Univ. Bordeaux, IMS, UMR 5218, F-33400 Talence, France isabelle.dufour@ims-bordeaux.fr Univ. Bordeaux, LOMA, UMR 5798, F-33400 Talence, France 3 LAAS CNRS, F-31077 Toulouse, France 4 Univ. Bordeaux, LOF, UMR 5258, F-33600 Pessac, France

2

The classical way to measure the rheological properties of fluids is either to use a viscometer (involving a falling or rolling ball) or a rheometer (utilizing the rotational motion of a cone/plate or Couette flow). Whereas viscometers can only characterize the viscous component of the deformation, rheometers can characterize both elastic and viscous responses. However, the latter have also several drawbacks: the measurement cannot be made in situ (a fluid sample is needed), the amount of fluid necessary to make the measurement is quite large (a few milliliters) and the measurement is limited to low frequency (less than 200 Hz due to inertial issues). To overcome the frequency range limitation, some alternative methods have been developed over the two last decades, giving raise to the field of ‘microrheology’, which involves the measurement of the movement of monodispersed beads (microspheres) immersed in the fluid. In the presentation we will present two alternative methods based on the use of silicon MicroElectroMechanical Systems (MEMS). Both methods are based on the measurement of the hydrodynamic force exerted on a solid body moving in a fluid, which depends on the fluid’s rheological properties. In the first method the moving solid body is a sphere attached to the microcantilever and the force measurement is made using the microcantilever, similar to what is done in AFM systems. In the second method the microcantilever has a dual role: it is used to actuate the fluid flow as well as to measure the hydrodynamic force. Thus, both methods are based on the ability to relate the free-end cantilever deflection to the fluid’s rheological properties through analytical equations. Both principles have already been used by the authors or other teams to measure the viscosity of Newtonian fluids (fluids with constant real part of viscosity and no imaginary part of viscosity). The originality of the presented work comes from the fact that thanks to analytical modeling these methods have been extended to the measurement of the complex viscosity or of the complex shear modulus which characterize both the elastic and viscous behavior of complex fluids. Acknowledgements This work has been partially supported by the French National Agency (ANR) in the frame of its program in Nanosciences and Nanotechnologies (MicRheo project n°ANR-08-NANO-004); by the CPER Pôle 4N Nanosciences en Aquitaine (GP 206-action 216/1) with the contribution of the Conseil Régional d’Aquitaine, the FEDER and the Ministry of Education and Research; and by the Conseil Régional Aquitaine (project MicRhéo-Aquitaine 2009-1102001).

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Peptides in the design of theranostic nanocarriers Elisabeth Garanger, Didier Boturyn, Jean-Luc Coll, Pascal Dumy, Marie-Christine Favrot, Lee Josephson, Sébastien Lecommandoux (a) Laboratoire de Chimie des Polymères Organiques, Université de Bordeaux, CNRS, UMR 5629, 16 avenue Pey-Berland, 33607 Pessac, France (b) Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac, France garanger@enscbp.fr

Peptides are small biopolymers of amino acids that are extensively used in the design of materials for biological and biomedical applications. Their intrinsic biological activity can be exploited to develop targetspecific drugs, substrates or ligands. Their functional building blocks can also serve as anchoring sites in the design of templates and scaffolds. Their bi-and tridimensional organizations can also be used in the design of bioactive self-assembled nanomaterials. The present communication will illustrate the use of peptides in these three different fields. Multivalent tumor-targeting peptide vectors were designed from a cyclic decapeptide template to carry molecular imaging agents and deliver cytotoxic drugs.[1,2] Multifunctional Single-Attachment-Point (MSAP) reagents were developed from di- and tetrapeptide scaffolds to modify biomolecules at a single position with multiple functionalities.[3] Chimeric and recombinant polymer-peptide materials, featuring a hydrophobic or thermo-responsive polymer block and a peptide segment, are currently investigated to develop bioactive self-assembled nanomaterials.[4]

References [1]

[2] [3]

[4]

E. Garanger, D. Boturyn, O. Renaudet, E. Defrancq, P. Dumy, Journal of Organic Chemistry, 71 (2006) 2402-2410; E. Garanger, D. Boturyn, J.L. Coll, M.C. Favrot, P. Dumy, Organic Biomolecular Chemistry, 4 (2006) 1958-1965. E. Garanger, D. Boturyn, Z.H. Jin, P. Dumy, M.C. Favrot, J.L. Coll, Molecular Therapy, 12 (2005) 1168-1175. E. Garanger, E. Aikawa, F. Reynolds, R. Weissleder, L. Josephson, Chemical Communications, 39 (2008) 4792-4794; E. Garanger, J.T. Blois, S.A. Hilderbrand, F. Shao, L. Josephson, Journal of Combinatorial Chemistry, 12 (2010) 57-64. E. Garanger, S. Lecommandoux, Angewandte Chemie International Edition, (2012) DOI: 10.1002/anie.201107734.

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DFT characterization of solid surfaces: interpretation of XPS experiments and H adsorption on silicates S. García-Gil1,2,3 1 CEMES-CNRS; 29 rue Jeanne-Marvig,F-31055 Toulouse, France CIN2-CSIC; Campus de la U.A.B. 08193 Bellaterra, Barcelona, Spain 3 ISMO-CNRS ; Université Paris Sud, F-91405 Orsay, France sandra.garcia-gil@cemes.fr

2

The importance of systems at the atomic scale has increased very quickly in the past few years. Experimental techniques are more powerful and allow a very high resolution, offering the real possibility to design, manipulate and understand a wide variety of systems. The applications are innumerable and almost in every field: diagnosis and drug delivery in medicine, increase of speed in a given reaction with nanoparticles as catalysis, energy storage, new semiconductor devices and astrophysics, to cite some of them. Of all the experimental techniques, I would remark scanning tunneling microscopy (STM) and X-Ray photoemission spectroscopy (XPS). This experiments can benefit greatly from the basic understanding provided by theoretical calculations. One clear example is the interpretation of STM images and STS spectra, which is often very difficult without the reference provided by calculated images from electronic structures. Another example is the core level binding energy spectra obtained with XPS, in which sometimes the attributions of parts of the obtained spectra to particular atoms or structures are not always very simple or straighforward without resorting the reference provided by theory. This presentation deals mainly with the description of different solid surfaces and interfaces from a theoretical point of view, using Density Functional Theory and the Siesta [1] code. The first part is based on the implementation within the SIESTA framework of two approximations to determine the core level electron binding energy shifts as obtained in an XPS experiment: the initial and the final state approximations [2]. Some case studies will be presented for isolated molecules, metallic surfaces [3] and semiconductors. In a second part, an application of DFT in the huge field of the astrophysics of the interstellar medium (ISM). The formation of molecular hydrogen is still an open question due to the particular conditions of this medium (UV radiation, temperatures). Since the early 60's, interstellar dust particles are invoked as possible mediators of molecular hydrogen formation [4]. Experimental evidences indicate that they have both a carbonateous and silicateous composition. A DFT study of the interaction of the H atom with the Forsterite surface is presented. The characterization of the properties of its adsorption and the posibility of formation of molecular hydrogen will be discussed. References [1] [2] [3] [4]

J. M. Soler, E. Artacho,J. D. Gale, A. García, J. Junquera, P. Ordejón, and D. Sánchez-Portal, J. Phys.: Condens. Matt. 14, 2745-2779 (2002). S. García-Gil. PhD thesis, Universitat Autonoma de Barcelona, April 2011. J. Fraixedas, S. Garcia-Gil, S. Monturet, N. Lorente, I. Fernandez-Torrente, K. J. Franke, J. I. Pascual, A. Vollmer, R.-P. Blum, N. Koch, P. Ordejon, J. Phys. Chem. C 115, 18640 (2011). N. Rougeau, D. Teillet-Billy and V. Sidis, Phys.Chem. Chem. Phys., 2011,13,17579 17587

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Nanostructured Energetic Materials: Fabrication process and atomic scale modeling C. Lanthony1,2, J.M. Ducéré1,2, M.M. Bahrami1,2, G. Taton1,2, A. Hemeryck1,2, C. Rossi1,2, A. Estève1,2, ,G. Landa1,2, M. Djafari Rouhani1,2 1

CNRS; LAAS; 7 avenue du colonel Roche, F-31077 Toulouse, France Université de Toulouse; UPS, INSA, INP, ISAE; UT1, UTM, LAAS ; F-31077 Toulouse, France

2

Nanoenergetic materials and reactive nanolaminates have attracted great interest in the energy generating material community since they are characterized by a high energy density (superior to supercapacitors), are low cost and safe. In recent years, ideas have emerged to integrate them into micro and nanosystems opening the route to nanoenergetics on a chip with applications in civilian as well as military fields: environmentally safe and clean primers and detonators, smart and fast fuses, nanoscale heat sources for biological and chemical neutralization and disease treatment. At LAAS, our team is already oriented towards the creation of new generations of nanostructured energetic materials and nanolaminates. Al-CuO nanolaminates are magnetron sputter deposited from Al and Cu targets using DC power supplied, on oxidized silicon wafer. Many hundreds of nanometer thick layers can be stacked by alternating oxidizer and fuel. Each reactant layer thickness can be accurately set at +/- 5nm and the layering also places the reactants in intimate contact leading to a reduction of the diffusion distance by a factor of 10-1000 compared to the same material traditionally prepared by powder mixing. During vapor deposition, invariably an intermixing occurs at the Al and CuO interface. These intermixed interfaces play a critical role during the synthesis and the utilization of the material. The formation of interfacial layers is not only poorly understood but uncontrolled at present. An understanding of the formation, role and control of these interfacial layers is among the most important technological issues in highly reactive materials. We have developed atomic scale process simulation based on DFT calculations to depict elementary chemical and also incorporating a novel accelerated Molecular Dynamics scheme (hyperthermal Kinetic Monte Carlo) into conventional Kinetic Monte Carlo to overcome issues associated with exothermic reactions. This will lay the foundation of a TCAD (Technology Computer Aided Design) dedicated to reactive nanolaminates. A second technological approach, also developed at LAAS, is to direct the assembly of nanoparticles of Al and CuO into a micron size Al-CuO composite particle thanks to DNA strands [1]. While the potential of this technology has been recently demonstrated in the liquid phase (AFM), surface integration is still an open issue. Because of the biohybrid intrinsic complexity of these systems, a fundamental basic understanding is required. First principles calculation are therefore combined with technology to guide the assembly procedure and choices: surface modification strategy, grafting, solvent issues… Besides this work, clean room facilities and infrastructures of LAAS, as the activities around the project TRAIN2, will be discussed. References [1]

F. Séverac et al., Adv. Func. Mat. 22 (212) 323.

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Colloidal architectures for plasmonics Renaud Vallée, Mélanie Ferrié, Serge Ravaine Centre de Recherche Paul Pascal (CNRS), 115 avenue docteur Schweitzer, 33600 Pessac, France vallee@crpp-bordeaux.cnrs.fr

We present several colloidal architectures able to generate plasmonics effects, leading to the observation of new resonance modes and possibly to surface enhanced fluorescence. In a fist approach [1], we present a nanofabrication method which combines bottom-up and top-down techniques to realize nanosized curved Fabry–Pérot cavities. These cavities are made of a hexagonal closed packed monolayer of silica particles enclosed between flat and curved metallic mirrors. They exhibit geometric cavity modes such as those found in gold shell colloids. These modes manifest as dips in the reflection spectra which shift as a function of the diameter of the used nanoparticles. An excellent agreement is found between experiment and theory which allows us to properly interpret our data. In particular, owing to FDTD simulations, we could discriminate between dipolar and quadripolar resonances which result from the coupling of cavity modes and plasmonic collective modes. The strong exaltations observed in the vicinity of the front gold curved mirror are of particular interest: potential emitters could be inserted by functionalization at these positions and benefit of the maximum field. This feature could prove very important for applications as nanoscale light sources, sensors, or lasers. In a second approach [2], owing to the competition between the radiative and nonradiative decay channels occurring in plasmonic assemblies, we show how to conceive a long pass emission filter and actually design it. We report the synthesis of gold@silica nanoparticles grafted with dye molecules. The control of the thickness of the silica shell allows us to tune the distance between the metal core and the dye molecules. Assemblies of small number (1 to 7) of these core-shell (CS) particles, considered as multimers, have also been produced for the first time. We show that the shaping of the emission spectra of the multimers is drastically enhanced by comparison with the corresponding monomers. We also show a strong enhancement of the decay rates at the LSP resonance, dominated by the non-radiative energy tranfer from the active medium to the metal. The decay rates decrease as the detuning between the long wavelength emission and the LSP resonance increases In a third approach [3], We numerically investigate end experimentally demonstrate the influence of the interaction of localized and propagating surface plasmon polaritons on the resonances exhibited by metallic structures. The structure under investigation is an hexagonal close packed array of gold core – silica shell nanoparticles (NPs) sandwiched either between two gold films or in contact with a single gold film. We show that sandwiching the NP array between two gold films significantly enhances the amplitude of specific resonances as compared to the same NP array in contact with a single gold film. The robustness of the optical properties exhibited by the sandwiched structure against disorder makes it an ideal candidate for further investigations. In particular, this structure might be able to promote a broadband enhancement of the decay rates of emitters embedded in. References [1] [2]

[3]

S. Mornet, L. Teule-Gay, D. Talaga, S. Ravaine and R.A.L. Vallée "Optical cavity modes in semicurved Fabry–Pérot resonators", J. Appl. Phys., 108 (2010) 086109. M. Ferrié, N. Pinna, S. Ravaine and R.A.L. Vallée "Wavelength - dependent emission enhancement through the design of active plasmonic nanoantennas", Optics Express, 19, 18 (2011) 17697. R. A. L. Vallée, M. Ferrié, H. Saadaoui and S. Ravaine “Interaction between localized and propagating surface plasmons in arrays of core-shell metallic nanoparticles sandwiched between metallic surfaces”, submitted.

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Keynote Speakers Parallel Sessions

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Molecules as Prototypes for Spin-Based CNOT and SWAP Quantum Gates Guillem Aromí,1 Fernando Luis,2 Olivier Roubeau,2 David Aguilà,1 Leoní A. Barrios,1 Ana Repollés,2 M. J. Martínez-Pérez,2 P. J. Alonso,2 2

1 Universitat de Barcelona, Departament de Química Inorgànica, Diagonal 645, 08028 Barcelona, Spain Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC–Universidad de Zaragoza, and Departamento de Física de la Materia Condensada, Universidad de Zaragoza, E-50009 Zaragoza, Spain guillem.aromi@qi.ub.es

The implementation of Quantum Computing relies to a great extent on the capacity to develop the suitable technology for realizing and coherently manipulating quantum bits (qubits) and quatum gates (QGs). Recent proposals suggest that electronic spins would be good candidates to embody the basic quantum information.[1-3] In particular, the states of the total angular momentum of rare earths (RE) have been found to exhibit appropriate coherence times and they could be addressed with local pulses of a magnetic field.[4] In this context, the unlimited versatility of chemical design and synthesis should allow producing suitable molecules as carriers of RE, adapted for the realization of logic operations. The universal gate of quantum computing is the CNOT, which operates on two coupled qubits, by flipping the target qubit depending on the state of the control qubit. By use of a novel asymmetric multidonor ligand (H3L), we have developed methods for the preparation of coordination complexes of two weakly coupled lanthanides, [Ln2X(HL)2(H2L)(H2O)(py)] (X=Cl− or NO3−), where each metal lies in a dissimilar coordination environment.[5] This asymmetry provides for a magnetic inequivalence, which, coupled to the strong anisotropy of RE, constitutes a good definition of control and target qubits. The robustness of this chemical synthetic scheme allows for the preparation of analogous molecules of various lanthanide metals. A combination of ac susceptibility, magnetization and heat capacity studies performed in the vicinity of the absolute zero, shows that the member of this family with Tb3+ ions meets the ingredients required to implement a CNOT quantum gate.[6] The difference of coordination sites featured in this complexes suggest the possibility of generating analogous complexes containing two different RE ions almost at will, by taking advantage of their different ionic radii. Given the intrinsic difficulty in making heterometallic 4f4f’ discrete molecules, such an achievement would be of great importance in lanthanide coordination chemistry. On the other hand, this flexibility would enable a vast choice of quantum gate designs. The success of this designed synthetic strategy will be presented.

References [1] [2] [3] [4] [5] [6]

F. Troiani, M. Affronte, Chem. Soc. Rev. 40, (2011) 3119-3129. G. A. Timco, T. B. Faust, F. Tuna, R. E. P. Winpenny, Chem. Soc. Rev. 40, (2011) 3067-3075. G. Aromí, D. Aguilà, P. Gamez, F. Luis, O. Roubeau, Chem. Soc. Rev. 41, (2012) 537–546. S. Bertaina, S. Gambarelli, A. Tkachuk, I. N. Kurkin, B. Malkin, A. Stepanov, B. Barbara Nat. Nanotech. 2 (2007) 39-42. D Aguilà, L. A. Barrios, F. Luis, A. Repollès, O. Roubeau, S. J. Teat, G. Aromí Inorg. Chem. 49 (2010) 6784–6786. F. Luis, A. Repollés, M. J. Martínez-Pérez, D. Aguilà, O. Roubeau, D. Zueco, P. J. Alonso, M. Evangelisti, A. Camón, J. Sesé, L. A. Barrios, G. Aromí Phys. Rev. Lett., 107, (2011) 117203.

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Application of synthetic biology to the development of smart therapeutic nanosystems against cancer Guillermo de la Cueva Méndez, Belén Pimentel, Adriana Arnáiz, Mark Preston, Alice Turnbull, Camino Bermejo, Chukwuma Agu and Isabelle Dionne Andalusian Centre of Nanomedicine and Biotechnology. C/Severo Ochoa, 35. Parque Tecnológico de Andalucía. 29590 Campanillas, Málaga. Spain and Hutchison/MRC Research Centre. Cancer Cell Unit. Hills Road, CB2 0XZ Cambridge, United Kingdom. gdelacueva@bionand.es

Our understanding of the molecular and cellular basis of cancer has improved considerably over the past few decades. However, this has not been paralleled by proportional increases in long-term survival rates of patients affected by the disease, which still remains the second leading cause of death in Europe and North America. Pharmacological treatment of cancer requires potent inducers of cell death that are also very selective. Classical chemotherapeutic agents are very effective at killing cells but display poor selectivity, leading to excessive collateral damage and limiting their efficacy and clinical application. Molecularly targeted drugs, developed with the advent of functional genomics and high throughput technologies, are more selective than classical chemotherapeutic agents. However, too frequently these compounds do not induce significant cancer cell killing, which also has negative implications for therapeutic outcomes. Innovative approaches are required to treat cancer effectively. Ideally, these therapeutic strategies should display killing efficiencies similar to those observed with classical chemotherapeutic agents, and target selectivities like those featured by molecularly targeted drugs. Synthetic biology is an emerging field of research that applies engineering principles to the design and construction of artificial biological systems capable of executing pre-determined functions with great control and precision. Following this approach, our laboratory has produced synthetic systems capable of distinguishing cancerous cells from normal cells, and of exploiting cancer biomarkers to promote the suicide of tumor cells whilst conferring active protection to normal cells to avoid off-target cytotoxicity. These systems, their performance, future potential and limitations will be presented and discussed.

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Quantum nanosystems based on graphene E Diez1, C. Cobaleda1, M. Amado1,*, C.H. Fuentevilla1, J.D. Lejarreta1, A. González1,+, Y. Meziani1 J.M. Cerveró1, S. Pezzini2, F. Rossella2, V. Bellani2, D. López-Romero3, D. K. Maude4 1 Laboratorio de Bajas Temperaturas, Universidad de Salamanca, E-37008 Salamanca, Spain Dipartimento di Fisica “A. Volta” and CNISM, Università degli studi di Pavia, I-27100 Pavia, Italy 3 CT-ISOM, Universidad Politécnica de Madrid, E-28040 Madrid, Spain 4 Laboratoire National des Champs Magnetiques Intenses, CNRS, F-38042 Grenoble, France * SNS-NEST & CNR, Piazza San Silvestro 12, 56127 Pisa, Italy + Physikalisches Institut, Albert-Ludwigs Universität Freiburg. Hermann-Herder Str. 3, D-79104, Freiburg, Germany. 2

Relativistic and topological effects, as well as non-linear interactions and disorder, play a key role to determine the unique properties of graphene. Experimental measurements have revealed that electronic localization in graphene, in the quantum Hall regime, is not entirely dominated by single-particle physics, but rather a competition between the underlying disorder and the repulsive Coulomb interaction exists [1]. Indeed, the effect of interactions near the plateauplateau (PP) and plateau-insulator (PI) quantum phase transitions (QPT), and in particular the role of multifractality, are not well understood at the moment. For instance, at the Integer Quantum Hall transition short range interactions seem to be irrelevant, in a renormalization group sense, at the critical point, (i.e. the critical exponent ν for the localization length and the multifractal spectrum remain the same as in the non-interacting problem). The 1/r long-range Coulomb interaction is relevant, however, and should drive the system to a novel critical point. To measure experimentally the critical exponent of these transitions, we have studied the PI and PP QPTs in a wide temperature range (from 4 K up to 230 K) and at different gate voltages (VG) in graphene [2-7]. In the case of the PI ν = −2 to ν = 0 transition we have observed it up to 45 K, pointing out the robustness of the QPT and of the metal and insulating phases. The critical exponent for this transition is consistent with the accepted universal value for 2DEGs when the sample is doped away from the Dirac point (κ = 0.58 ± 0.01) but tends to the classical full percolation limit (ν = 0.697 ± 0.005) when VG approaches the charge neutrality point (CNP). We will present also our results on modelling of the transport properties of nanodevices based on graphene, along with their fabrication and experimental characterization. Because of its electrical properties, graphene is an interesting potential material to develop nanodevices usable in technological applications, such as field effect transistors (FET). We have modelised and fabricated FET’s based on graphene and analyzed its electrical transport capabilities based on an exact analytical solution to the Dirac equation [8]. We will show our preliminary results on terahertz (THz) spectroscopy and imaging using graphene transistors as room temperature THz detectors. This work was supported by the projects: Ministerio de Ciencia e Innovación (Spain): FIS2009-07880, PCT420000-2010-08 and PCT310000-2009-3; Junta de Castilla y León (Spain): SA049A10; Cariplo Foundation (Italy): QUANTDEV, and by EuroMagNET under the EU contract n. 228043.

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References [1] [2] [3] [4] [5] [6] [7] [8]

J. Martin et al., Nature Physics 5 (2009) 669 J.M. Caridad, F. Rosella, V. Bellani, M.S. Grandi and E. Diez Journal of Raman Spectroscopy 10 (2010) 2739 J.M. Caridad, F. Rosella, V. Bellani, M.S. Grandi and E. Diez Journal of Applied Physics 108 (2010) 084321 M. Amado, E. Diez, D. López-Romero, F. Rosella, J.M. Caridad, V. Bellani, D.K. Maude. New Journal of Physics 12 (2010) 053004 J.M. Cerveró, E. Diez. International Journal of Theoretical Physics 50 (2011) 2134 C. Cobaleda, F. Rossella, S. Pezzini, E.Diez, V. Bellani, D. Maude and P. Blake. Physica E 44 (2011) 530 M. Amado, E. Diez et al. (submitted) C. H. Fuentevilla,J.D. Lejarreta, C. Cobaleda and E. Diez (submitted)

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Figure 1: (a) Longitudinal resistance Rx x as a function of Δν with Δν = 1/B − 1/Bc and Bc = 16.7 T, at low temperatures and VG = -8 V; lower inset: log(Rx x ) vs B; upper inset: the parameter ν0 obtained fitting our data using the standard scaling κ procedure (Rxx= exp[-Δν/ ν0(T)], critical exponent ν0∝T )). (b) The analysis described in (a) but at higher T. (c) The analysis described in (a) but at higher T and VG = 2 V. (d) ρxx and ρxy as a function of B at VG = −8 V at temperature from 4.1 K to 230 K, showing the plateaus ν = −2,−6,−10 in ρxy an their Shubnikov-de Haas peaks.

Figure 2: Plot of source-drain current as a function of the source-drain voltage applying different top-gate voltages. The output cu rent remains almost unmodified even for a variation of the top gate range of nearly 80 V.


Graphene: a new platform for capturing and manipulating light at the nanoscale Frank Koppens ICFO, The institute of photonic Sciences, Barcelona (Spain) frank.koppens@icfo.es

In this talk, I will discuss recent experimental and theoretical work on exploiting graphene as a host for capturing, guiding, switching and manipulating light and at nanoscale dimensions. The first part of my talk will be devoted to the emerging and potentially far-reaching field of graphene plasmonics: surface waves coupled to the charge carrier excitations of the conducting sheet. Due to the unique characteristics of graphene, light can be squeezed into extremely small volumes and thus facilitate strongly enhanced lightmatter interactions[1]. I will discuss recent observations of propagating and localized optical plasmons in graphene nano-structures [2] (Figure, right panel). By gating the graphene, in-situ control of the plasmon wavelength is demonstrated, which allows us to control the resonance frequency of graphene-based plasmonic cavities. In particular, we demonstrate the capability to completely switch on and off plasmon modes in a graphene ribbon, paving the way towards graphene-based optical transistors. The second part of the talk is devoted to presenting a novel graphene-based phototransistor with extremely high photo-responsivity and gain [3] (Figure, left panel). The detection mechanism in these devices relies on the photo-gating effect caused by photo-generated charges trapped in quantum dots which decorate the graphene. Due to the combination of high absorption of light in the quantum dots, and the extremely high mobility in the graphene layer, a gain on the order of 108 is demonstrated. This highly sensitive photodetector can detect power in the fW regime while covering a broad spectral bandwidth, from the visible to the near infrared, and its responsivity can be tuned by electrostatic gates.

References [1] [2] [3]

Figures

Koppens, F. H. L., Chang, D. E. & García de Abajo, F. J. Graphene Plasmonics: A Platform for Strong Light–Matter Interactions. Nano Lett 11, 3370–3377 (2011). In preparation Konstantatos, G. et al. Hybrid graphene-quantum dot phototransistors with ultrahigh gain. arXiv 1112.4730 (2011).

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Plasmonic nanoparticle chain in a light field: a resonant optical sail Silvia Albaladejo, Juan José Sáenz and Manuel I. Marqués Departamento de Física de la Materia Condensada and Instituto “Nicolás Cabrera”, Universidad Autónoma de Madrid, 28049 Madrid, Spain.

Optical trapping and driving of small objects has become a topic of increasing interest in multidisciplinary sciences. We propose [1] to use a chain made of metallic nanoparticles as a resonant light sail, attached by one end point to a transparent object and propelling it by the use of electromagnetic radiation. Driving forces exerted on the chain are theoretically studied as a function of radiation’s wavelength and chain’s alignments with respect to the direction of radiation. Interestingly, there is a window in the frequency spectrum in which null torque equilibrium configuration, with minimum geometric cross section, corresponds to a maximum in the driving force.

References [1]

S. Albaladejo, J. J. Sáenz and nd M. I. Marqués, Nanoletters 11, 4597 (2011)

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Gated Materials in Delivery Applications Ramón Martínez-Máñeza,b,c a

Centro de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), Unidad Mixta Universitat Politècnica de Valencia Universitat de Valencia, Spain b Departamento de Química, Universitat Politècnica de Valencia, Camino de Vera s/n, 46022, Valencia, Spain c CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN) rmaez@qim.upv.es

Gated nanochemistry, although highly topical and rapidly developing, is still in its infancy. Recently some research groups have demonstrated the possible incorporation of “gates” into mesoporous supports. In this field, molecular or supramolecular gates can be defined as nanoscopic supramolecular-based devices in which mass transport can be triggered by a target external stimulus that can control the state of the gate; i.e., closed or open. A graphical representation of a gate-like superstructure is shown in Figure 1. In fact in the last few years, nano-containers bearing gated scaffoldings have proved to be excellent candidates for the design of controlled-release “nano-machines” at different levels. For instance in the treatments of specific pathologies, e.g., cancer, highly toxic drugs have been used and a number of efforts have been made to design carriers to shield them until they are released at the target tissue or cell. However, the release mechanism of many current biodegradable polymer-based drug delivery systems simply relies on the hydrolysis-induced erosion of the carrier structure. To avoid this problem, the use of gated ensembles built up using silica mesoporous materials containing on-off triggered gate ensembles could be of importance. These systems show an ideal “zero release” until opened via a suitable stimulus. Mesoporous supports show stable structures (pores of ca. 2-3 nm), large surface areas (up to 1200 m2/g), tunable pore sizes and volumes, and well-defined surface properties for site-specific delivery and for hosting molecules. The mesoporous support can additionally be obtained in a nanometric size, resulting in suitable materials for the design of “nanodevices” for the controlled delivery of drugs and other species. Moreover, a second more novel application involves the use of gated material in sensing protocols. In particular, very few works currently demonstrate the suitability of such objects for (bio)chemical sensing. In that case the concept involves designing capped materials capable of being opened in the presence of a target guest that triggers the delivery of a dye or fluorophore. Examples of triggered gated materials able to deliver their cargo by changes in the pH,[1] temperature,[2] irradiation with light,[3] and by the presence of small molecules [4] or biomolecules [5] will be shown. References [1] [2] [3] [4] [5]

R. Casasús, E. Climent, M. D. Marcos, R. Martínez-Máñez; F. Sancenón, J. Soto, P. Amorós, J. Cano, E. Ruiz, J. Am. Chem. Soc., 130 (2008) 1903. E. Aznar, L. Mondragón, J. V. Ros-Lis, F. Sancenón, M. D. Marcos, R. Martínez-Máñez, J. Soto, E. Pérez-Payá, P. Amorós, Angew. Chem. Int. Ed., 50 (2011) 11172. E. Aznar, M. D. Marcos, R. Martínez-Máñez, F. Sancenón, J. Soto, P. Amorós, C. Guillem, J. Am. Chem. Soc., 131 (2009) 6833. R. Casasús, E. Aznar, M. D. Marcos, R. Martínez-Máñez, F. Sancenón, J. Soto, P. Amorós, Angew. Chem. Int. Ed., 45 (2006) 6661. E. Climent, A. Bernardos, R. Martínez-Máñez, A. Maquieira, M. D. Marcos, N. Pastor-Navarro, R. Puchades, F. Sancenón, J. Soto, P. Amorós, J. Am. Chem. Soc., 131 (2009) 14075. E. Climent, R. Martínez-Máñez, F. Sancenón, M. D. Marcos, J. Soto, A. Maquieira, P. Amorós, Angew. Chem. Int. Ed., 49 (2010) 7281. C. Coll, L. Mondragón, R. Martínez-Máñez, F. Sancenón, M. D. Marcos, J. Soto, P. Amorós, E. Pérez-Payá, Angew. Chem. Int. Ed., 50 (2011) 2138.

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External stimulus

Figure 1: A schematic representation of a gated material showing stimulus-controlled delivery.

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Single nanoparticle Plasmonics: Shape matters R. Rodríguez-Oliveros, R. Paniagua-Domínguez, F. López-Tejeira, L. Froufe-Pérez, J. A. Sánchez-Gil Instituto de Estructura de la Materia (IEM-CSIC), Consejo Superior de Investigaciones Científicas Serrano 121, 28006 Madrid, Spain j.sanchez@csic.es

Metal nanoparticles exhibit a rich optical phenomenology due to the excitation of localized surface plasmons (LSPs). These resonances stem from the oscillations of free electrons, inducing a dipole with a resonance frequency typically in the visible [1]. In recent years, advances in nanofabrication techniques have made feasible a great variety of nanoparticle configurations, which have in turn fuelled interest in LSP resonances in metal nanostructures, giving rise to the concept of optical nanoantennas (cf. Ref. [1,2] and references therein). Concentrating light into small volumes leads to fascinating phenomena. LSPs supported by pairs of nanoparticles with a small gap between them [1-4] are able to greatly amplify local EM fields and the photonic local density of states, making these structures ideal for use in SERS and surface-enhanced fluorescence [2-5]. A special type of LSP resonances are highly promising for potential applications due to the extremely narrow (asymmetric) line shapes and fine sensitivity to environment changes: Fano LSP resonances [6]. Nanoantennas are also extremely suitable for biological applications because they enable the tracking of emission from markers in cells with sub-diffraction limit resolution, as well as the destruction of cancer cells using the resistive heating of resonant nanoparticles [7]. In general, most of the appealing optical properties of metal nanoparticles typically manifest themselves in optically coupled nanoparticles with stronger LSPs [2]. Namely, extremely large near-field and LDOS enhancements arise at resonance in gap nanoantenas and nanoparticle dimers (or aggregates), responsible for SERS and fluorescence. Fano LSP resonances also require complex multi-particle configurations involving wide, dipolar modes with narrow, dark modes. In this regard, we have investigated theoretically and numerically the optical properties of isolated nanoparticles with the aim of exploring how complex shapes might yield similar or improved phenomenology. First, in connection with SERS, we have studied so called nanostars or nanoflowers [8,9], as described by, respectively, a 3D supershape formula [10] without axial symmetry and low-order Chebyshev 2D nanoparticles. Large field intensity enhancements are obtained both at the intersticies between nanoflower petals and at the nanostar tips, which make these Ag nanostars/nanoflowers specially suitable to host molecules for SERS spectroscopy and sensing applications, without the commonly needed aggregation. Not surprisingly, we have shown, by exploiting genetic optimization algorithms, that such shapes lead, among a variety of them, to maximized LSP cross sections [11]. Moreover, based on a simple model for temperature increase obtained from the calculated absorption cross section, Au nanostars have been shown to perform more than an order of magnitude better that Au nanospheres of equivalent size, due to their LSP in the near-IR [12]. Actually, these features hold promise for applications in photothermal cancer therapy. On the other hand, we have evidenced that (single) elongated Ag nanoparticles such as nanospheroids, nanorods, and rectangular nanowires, suffice to exhibit asymmetric (Fano) resonances as a consequence of the interference between the broad, (dipole-like) half-wavelength mode, with dark, higher-order modes [13]; unlike the commonly belief (based on Mie theory) that coupled nanoparticles are necessary [6]. Finally, metal-dielectric (core-shell) nanoparticles have been investigated with the aim of obtaining electric (LSP) and magnetic resonances overlapping in the optical spectral regime [14,15]. Their use as building blocks for negative-index metamaterials in the visible range of the spectrum has been pointed out; again, single (core-shell) nanoparticles exhibit both resonances, making unnecessary multiplenanoparticle configurations.

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The research presented in this contribution is supported by the Spanish “Ministerio de Economía y Competitividad” (projects Consolider-Ingenio EMET CSD2008-00066 and NANOPLAS FIS2009-11264) and the “Comunidad de Madrid” (MICROSERES II network S2009/TIC-1476). R. Paniagua-Domínguez acknowledges support from CSIC through a JAE-Pre grant. References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13]

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[14] [15]

Giannini, V.; Fernández-Domínguez, A. I.; Heck, S. C.; and Maier, S. A., Chem. Rev. 111 (2011) 3888. Halas, N. J.; Lal, S.; Chang, W.-S. ; Link, S. ; Nordlander, P., Chem. Rev. 111 (2011) 3913. Mühlschlegel, P.; Eisler, H.-J.; Martin, O. J. F.; Hecht, B.; Pohl, D.W., Science 308 (2005) 1607. Muskens, O. L.; Giannini, V.; Sanchez-Gil, J. A.; Gómez Rivas, J., Nano Lett. 7 (2007) 2871. Taminiau, T. H.; Stefani, F. D.; Segerink, F. B.; van Hulst, N. F., Nat. Photonics 2 (2008) 234. Luk’yanchuk, B.; Zheludev, N. I.; Maier, S. A; Halas, N. J.; Nordlander, P.; Giessen, H.; Chong, C. T., Nat. Mater. 9 (2010) 707. Jain, P. K.; El-Hayed, I.H.; El-Sayed, M.A., Nano Today 7, (2007) 1929. Giannini, V.; Rodríguez-Oliveros, R.; Sánchez-Gil, J. A., Plasmonics 5 (2010) 99. Rodríguez-Oliveros, R.; Sánchez-Gil, J. A., Opt. Express 19 (2011) 12208. Gielis, J., Am. J. Bot. 90 (2003) 333. Tassadit, A.; Macías, D.; Sánchez-Gil, J. A.; Adam, P.-M.; Rodríguez-Oliveros, R., Superlattices & Microstructures 49 (2011) 288. Rodríguez-Oliveros, R.; Sánchez-Gil, J. A., Opt. Express 20 (2012) 621; highlighted in ScienceShot: Gold Nanostars for Attacking Cancer, Jan. 6 (2012). López-Tejeira, F.; Paniagua-Domínguez, R.; Rodríguez-Oliveros, R.; Sánchez-Gil, J. A., New. J. Phys., in press, preliminary version at arXiv: 1111.3551. Paniagua-Domínguez, R.; López-Tejeira, F.; Marqués, R.; Sánchez-Gil, J. A., New J. Phys. 13, (2011) 123017. García-Etxarri, A.; Gómez-Medina, R.; Froufe-Pérez, L. S.; López C.; Chantada, L.; Scheffold, F.; Aizpurua, J.; Nieto-Vesperinas, M.; Sáenz, J. J., Opt. Express 19 (2011) 4815.

Figures

Figure 1: Distribution of electric field amplitudes in logarithmic scale on the surface of the Au nanostars at their corresponding LSP resonance wavelengths for an incident electric field polarized within the equatorial plane [12].

Figure 2: Schematic representation of the physics behind the core-shell nanoparticle configuration. The strong diamagnetic response is due to the lowest, dipolar magnetic resonance in the highpermittivity shell, where the electric field is forced to rotate as a consequence of the abrupt continuity conditions for the normal component between the shell and the surrounding medium. The electric resonance is a LSP resonance in the metal core [14].


Coordination polymers as a source of functional nanomaterials Félix Zamora,1 Julio Gómez-Herrero,2 Cristina Gómez,2 Cristina Hermosa,1 Rubén Mas-Ballesté,1 Gonzalo Givaja,1 Mohamad-Reza Azani,1 and Pilar Amo-Ochoa.1 1

Departamento de Química Inorgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid 28049. felix.zamora@uam.es Departamento de Física de la Materia Condensada, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid 28049.

2

Coordination polymers, also named metal-organic frameworks (MOF), are infinite aggregates of metal ions bridged by organic ligands.[1] They self-assemble by coordination bonding in one, two or three dimensions (1D, 2D and 3D). The key aspect to the design of a desirable polymer architecture and its dimension is the selection of the molecular building blocks, which also determines the properties of the resulting materials. Among other functions, these compounds form porous materials and polymer magnets, and they can show chromism, nonlinear optical properties, redox properties and electrical conduction.[2, 3] Most of the studies concerning these properties and potentials application have been carried out at the macroscale. These features have prompted studies focused on the development of suitable strategies towards their processability as nanomaterials.[4-6] In this talk several aspects concerning the formation of nanomaterials based on coordination polymers of different dimensionalities will be summarized. By means of some selected examples we will show several strategies that have allowed processability to produce 0D, 1D and 2D nanomaterials. Particular attention will be paid to the potential use as molecular wires of electrical conductive 1D nanostructures formed on insulated surfaces (Figure 1),[7] and 2D nanomaterials isolated on surfaces as alternative materials to graphene (Figure 2)[8]. References [1] [2] [3] [4] [5] [6] [7] [8]

C. Janiak, Dalton Trans., 2003, 2781-2804. S. R. Batten, S. M. Neville and D. Turner, Coordination Polymers: Design, Analysis and Applications, RSC Publishing, Cambridge, UK, 2009. G. Givaja, P. Amo-Ochoa, C. J. Gómez-García and F. Zamora, Chem. Soc. Rev., 2012, 41, 115– 147. A. Carne, C. Carbonell, I. Imaz and D. Maspoch, Chem. Soc. Rev., 2011, 40, 291-305. R. Mas-Balleste, C. Gomez-Navarro, J. Gomez-Herrero and F. Zamora, Nanoscale, 2011, 3, 2030. R. Mas-Balleste, J. Gomez-Herrero and F. Zamora, Chem. Soc. Rev., 2010, 39, 4220-4233. L. Welte, A. Calzolari, R. di Felice, F. Zamora and J. Gómez-Herrero, Nat. Nano., 2010, 5, 110115. P. Amo-Ochoa, L. Welte, R. González-Prieto, P. J. Sanz Miguel, C. J. Gómez-García, E. MateoMartí, S. Delgado, J. Gómez-Herrero and F. Zamora, Chem. Commun., 2010, 46, 3262–3264.

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Figures

Figura 1: Electrical characterization of MMX nanoribbons using conductance AFM. AFM topography showing an MMX nanoribbon adsorbed on SiO2 and electrically connected to a gold electrode. The nanoribbon is partially covered with gold and the protrusion observed on the gold electrode reflects the topography of the nanoribbon. For clarity, the scheme of the electrical circuit used in the AFM conductance experiments has been added to the AFM image.

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Figura 2: Structure of [Cu(pymS2)Cl•MeOH]n (pymS2=pyrimidine disulfide). AFM image of a single layer of 5x5 micron length deposited on SiO2 (F. Zamora, work in progress).


Orals - Plenary Session

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Plasmonic Antennas: From Optics to THz P. Albella1,2, P. Alonso-González2, D. Weber3, F. Neubrech3, A. Berrier4, J. Gómez-Rivas4, A. Pucci3, R. Hillenbrand2 and J. Aizpurua1 1

3

Material Physics Center CSIC-UPV/EHU and DIPC, Pº Manuel de Lardizabal 5, San Sebastián, Spain 2 CIC nanoGUNE, Avda Tolosa 76, 20018 San Sebastián, Spain Kirchhoff Institute for Physics, Univ. of Heidelberg, Im Neuenheimer Feld 227, Heidelberg, Germany 4 FOM Institute AMOLF, Centre for Nanophotonics,HTC4, 5656AE Eindhoven, The Netherlands 5 COBRA Research Institute, Eindhoven University of Technology, The Netherlands pablo_albella@ehu.es

Light scattering by nanoscale objects - such as atoms, molecules or nanoparticles - provides a valuable tool to obtain spectroscopic information on the electronic, optical and chemical properties of the object. This is possible because the incident light is converted into nanoscale confined and strongly enhanced optical fields (“hot spots”), thus acting as the optical analog of an antenna [1]. This considerable field enhancement and concentration is sensitive to changes in the geometrical and physical properties of the nanostructure, thus they can be widely exploited in many applications ranging from field-enhanced spectroscopy (SERS or SEIRA) to highly sensitive sensors in the THz [2,3]. In this contribution we study both optical and THz plasmonic antennas reporting on the performance of metallic antenna arrays as well as on semiconductor THz antennas for gas sensing. We first tackle the fieldenhanced spectroscopy techniques such as SERS or SEIRA, aiming at optimizing the resonant nanostructures. The interaction between particles in multimers and arrays of nanoantennas need to be carefully considered because it modifies and influences the optical response of the system. The properties derived from the interaction depend on the separation distances to adjacent neighboring antennas as well as on the distribution of the antennas within the array. Although, these effects have been broadly analyzed experimentally and theoretically in the visible spectral range for many different arrangements of particles [4], only few studies have analyzed the IR range [5], where retardation is especially important. In order to get a systematic knowledge on the relationship between infrared plasmonic resonances and longitudinal (dx) and transversal (dy) separation distances, we theoretically (by means of FDTD calculations) and experimentally (far-field extinction spectroscopy and near-field optical microscopy) studied the optical extinction spectra of rectangular ordered gold nanorod arrays on silicon wafers [6]. We also analyzed the role of a plasmonic antenna in the enhancement of spectroscopic signals. By means of a combined experimental and theoretical study of the signal scattered by a dielectric tip (probing object) in the proximity of a plasmonic linear antenna, we are able to reveal the double role of the antenna in the scattering, in both, incoming as well as outgoing radiation from the object. For the first time, dependence of the far field scattering on the fourth power of the field enhancement at the object positions, is quantitatively proven. This effect, commonly assumed in SERS is now evaluated by S-NOM. Furthermore, the double phase shift of the scattered radiation corroborates the double role of the antenna.

Figure 1: a) resonance wavelength vs rod length for different longitudinal rod separation distances. b) Measured intensity 2 2 4 In ∝ En (red symbols) and calculated field enhancement f and f (black and red solid lines, respectively) at the hot spot as a function of the antenna length L.

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Plasmonic antennas also show enhancing capabilities in the THz range of the spectrum and have a widely recognized potential for sensing owing to its capability to couple to various low-energy resonances of matter, including rotational and vibrational motion of molecules, as well as charge carriers and quasiparticles, such as plasmons, in semiconductors [7]. This ability to interrogate specific fingerprints of particular materials appears promising for the detection and recognition of strategic substances such as metals, explosives, gases, organic or biological substances. However, the wavelength of the THz radiation, e.g., 375 μm at 0.8 THz, makes the access to nanometric sensing volumes challenging. Conventional THz spectroscopy makes use of large amounts of matter (requiring flow cells of the order of 1 m for gas spectroscopy). The quest for finding mechanisms that enhance the signal of terahertz radiation in small volumes, hence reducing the amount of matter needed for THz spectroscopy, is therefore a natural drive in this field. Here, we show that bowtie antennas made of doped silicon operating as plasmonic resonators at THz frequencies are a versatile platform for thin film detection. Compared to metallic resonators, semiconductor-based structures are easily tunable and operate in a regime where the skin depth of the material is larger, i.e., the impedance is lower, and hence the coupling to surface plasmons is more pronounced. A structure such as a bowtie made of doped silicon provides large field confinement and enhancement in the region of its gap at THz frequencies [8]. When an inorganic thin film is deposited on top of the bowtie antenna, the area around the gap of the antenna thus provides an enhanced THz field that results in an enhanced interaction of the terahertz radiation with the deposited ultrathin inorganic films, allowing for THz spectroscopy in very small volumes. We experimentally demonstrate the in-situ detection of films that are orders of magnitude thinner than the wavelength using doped silicon bowtie antennas. In particular, we show that semiconductor bowtie antennas operating at THz frequencies allow the sensing of thin inorganic films with a layer thickness as small as λ/3750 in agreement with theoretical FDTD calculations.

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Figure 2: a) Schematic drawing of a silicon bowtie antenna covered with a TiO2 conformal layer. b) Resonance frequency shift induced by the presence of a SiO2 layer covering a doped silicon bowtie antenna as a function of the layer thickness (experiment (red circles) and FDTD calculations (black squares). The grey line is a guide to the eye.

The examples and results presented above show the importance of plasmonic antennas as versatile platforms for electromagnetic sensing in a broad range of the spectrum. References [1] [2] [3] [4] [5] [6] [7] [8]

M. Pelton, J. Aizpurua and G. Bryant, Laser Photon. Rev. 2, 136 (2008). A. Pucci, F. Neubrech, D. Weber, S. Hong, T. Toury, and M. Lamy de la Chapelle, Phys. Stat. Sol.(B), 247, 2071 (2010). H. Xu, E. J. Bjerneld, M. Käll and L. Börjesson, PRL, 83, (1999) 4357 L. L. Zhao, K. L. Kelly, and G. C. Schatz, J. Phys. Chem. B, 107, 7343–7350 (2003). J. Aizpurua, G. W. Bryant, L. J. Richter, F. J. García de Abajo, B. K. Kelley, and T. Mallouk, Phys. Rev. B 71, 235420 (2005). D. Weber, P. Albella, P. Alonso-González, F. Neubrech, H. Gui, T. Nagao, R. Hillenbrand, J. Aizpurua and A. Pucci, Opt. Express 19, 15047 (2011). R. Ulbricht, E. Hendry, J. Shan, T. F. Heinz, and M. Bonn, Reviews of Modern Physics, 83 543 (2011). A. Berrier, R. Ulbricht, M. Bonn and J. Gómez Rivas, Opt. Express 18 23226 (2010).


Integrated eBL Resist/Tobacco Mosaic Virus Structures for Micro- and Nanofluidics José María Alonsoa, Thierry Ondarcuhub, Andrey Chuvilina,c, Alexander Michael Bittnera,c a

CIC-nanoGUNE Consolider, Tolosa Hiribidea 76, 20018 Donostia-San Sebastián, Spain b CEMESCNRS,29 rue Jeanne Marvig, 31055 Toulouse Cedex 4, France c Ikerbasque, 48011 Bilbao, Spain jm.alonso@nanogune.eu

Tobacco mosaic virus (TMV) is an unusually resilient RNA/protein tube with a length of 300 nm, a diameter of 18 nm, and central channel 4 nm in width. It withstands pH values from 2.5 to 8.5, temperatures up to 90ºC, and a wide range of organic solvents . TMV is structurally and chemically well defined, very well characterized, and it has become a versatile biotemplate in the field of the nanosciences [1-4]. The properties of fluids and flow processes at the nanoscale, especially below 30 nm, are largely unknown. The main experimental hurdle is the design of channels or tubes (or other conducts) that are chemically and structurally well defined down to (nearly) atomic dimensions. We integrated single TMVs in microand nanofluidic devices, with the aid of nanofabrication techniques. E.g., electron beam lithography (eBL) was employed to construct hydrophobic barriers to prevent undesired fluid movement on TMV’s outer tube surface (Figure 1). Due to TMV’s surprising chemical and thermal stability, it is compatible with positive (PMMA) and negative (mrEBL6000.1) eBL resists (Figures 2,3), both spincoated from anisole solution. The key steps of the fabrication (prebaking of resists and development of the samples after eBL) were overcome by reducing the prebake temperature to 50 ºC, and by using only organic solvent in the development process. The successful binding of antibodies to the TMV surface shows that the virus particles are structurally and also chemically intact after the lithography process. References [1] [2] [3] [4]

Zhenyu Wu, Anna Mueller, Sven Degenhard, S. Emil Ruff, Fania Geiger, Alexander M. Bittner, Christina Wege, and Carl E. Krill III, ACS Nano, 4 (2010) 4531-4538. Anan Kadri, Edgar Maiß, Nadja Amsharov, Alexander M. Bittner, Sinan Balci, Klaus Kern, Holger Jeske, Christina Wege, Virus Research 157 (2011) 35-46. Anna Mueller, Fabian J. Eber, Carlos Azucena, Andre Petershans, Alexander M. Bittner, Hartmut Gliemann, Holger Jeske, and Christina Wege, ACS Nano, 5 (2011) 4512-4520. Sinan Balci, Kersten Hahn, Peter Kopold, Anan Kadri, Christina Wege, Klaus Kern and Alexander M Bittner, Nanotechnology, 23 (2012) 000.

Figures

Figure 1: Virus nanotube immobilization through negative resist mrEBL6000.1 (fabrication)

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Figure 2: TMV particle covered by a rectangular block of polymer resist (mrEBL6000.1). Image size: 3.7x3.4 Îźm

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Figure 3: TMV particles inside a polymer resist grid (PMMA). The particle at the bottom can be separately addressed by two liquid containers (left and right). Grid size: 4.1x2 Îźm


Real-Space Mapping of Fano Interference in Plasmonic Metamolecules P. Alonso-González1, M. Schnell1, P. Sarriugarte1, H. Sobhani2, C. Wu3, N. Arju3, A. Khanikaev3, F. Golmar4,5, P. Albella1,6, L. Arzubiaga4, F. Casanova4,7, L. E. Hueso4,7, P. Nordlander2, G. Shvets3 and R. Hillenbrand1,7 1

Nanooptics Group, CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian, Spain Department of Physics, Rice University, MS 61, Houston, Texas 77005, United States 3 Department of Physics, The University of Texas at Austin, One University Station C1600, Austin, Texas 78712, USA 4 Nanodevices Group, CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian, Spain 5 I.N.T.I.-CONICET, Av. Gral. Paz 5445, Ed. 42, B1650JKA, San Martín, Bs As, Argentina 6 Centro de Física de Materiales CSIC-UPV/EHU and DIPC, Paseo Manuel de Lardizabal 4, 20018, Donostia-San Sebastian Spain 7 IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain palonso@nanogue.eu 2

Fano resonances in plasmonic antennas have recently attracted great interest as they allow an unprecedented control of the antenna spectral response, opening the possibility for ultra-sensitive sensing applications [1]. The physical origin of the Fano resonances is the interference between two electromagnetic eigenmodes of the nanostructure, often referred to as “bright” and “dark”, that posses strongly differing radiative lifetimes. When both resonances are excited by the incident electromagnetic field, they contribute to the reflected field according to their dipole strength and lifetimes and, depending on the wavelength, exhibit either constructive or destructive interference in the far field. Up to now, the interpretation of such Fano interferences has been based on far-field spectroscopy and numerical calculations [2]. However, this characterization is both insufficient and ambiguous because different charge distributions can cause the same far-field scattering pattern. Here, we use interferometric scattering-type scanning near-field optical microscopy (s-SNOM) to experimentally verify for the first time the theoretically predicted near-field patterns of highly symmetric heptamer and asymmetric pi structures resonant at mid-infrared frequencies [3]. The results show a dramatic redistribution of the electric field intensity and phase across the structures as the Fano resonance is traversed (Figure 1), in excellent agreement with numerical calculations. The insight gained from near-field images will further our understanding of plasmonic Fano resonances and may open novel applications based on the spectral manipulation of plasmonic near fields.

References [1] [2] [3]

Liu, N. et al., Nano Letters 10 (2009), 1103-1107. Fan, J. A. et al., Science 328 (2010), 1135–1138. Alonso-Gonzalez, P. et al., Nano Letters 11 (2011), 3922-3926

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Figures a Si tip

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106 Figure 1: Real-space mapping of Fano interference in asymmetric PI-structures. (a) Experimental setup for near-field imaging in reflection mode. The PI-structure is illuminated from the side, with s-polarized light. Near-field imaging is performed by recording the tip-scattered radiation with an interferometer, yielding amplitude and phase images simultaneously to topography (grey image below). (b) Numerically calculated reflection spectrum for horizontal (blue) and vertical (red) polarization as indicated by the schematics. The letters mark the spectral positions where near-field imaging was performed. (c) Experimental (upper row) and calculated (lower row) amplitude |Ez| and phase ϕz images for horizontal polarization, recorded at 10.2 μm wavelength. (d) Experimental (upper row) and calculated (lower row) amplitude |Ez| images for vertical polarization, recorded at the spectral positions A-D marked in (b).


Dielectric and magnetic properties in Co- and Ni- containing ferrite/poly(vilidene fluoride) multiferroic nanocomposites J.M. Barandiarán1 , J. Gutiérrez1, P Martins2, C M Costa2, G. Botelho2 and S Lanceros-Mendez2 1

Departamento de Electricidad y Electrónica, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV/EHU, P. Box 644, E-48080, Bilbao, España 2 Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal josemanuel.barandiaran@ehu.es

Particulate composites films of poly(vinylidene fluoride) and CoFe2O4 and NiFe2O4 ferrites (supplied by Nanoamor, grain sizes between 35-55 nm and 20-30 nm for the Co- and Ni-containing ferrite, respectively) were prepared from solvent casting and melt processing. The weight percentage of ferrite nanoparticles varied from 0.001 to 50 in the case of Co-ferrite and 5 to 50 in the case of Ni-ferrite. X-ray diffraction studies demonstrate that ferrite nanoparticles nucleate the piezoelectric β-phase of the polymer, but the different ferrites nucleates the whole polymer phase at different concentrations [1] (see Fig. 1). The macroscopic dielectric response of the composites demonstrates a strong dependence on the weight fraction of ferrite nanoparticles. In all cases an increase of the ε’ for the composites with respect to the pure polymer sample has been observed. The inclusion of ferrite nanoparticles in the PVDF actually nucleates the β-phase of the material as the characteristics parameters of the β-relaxation of the polymer are maintained with respect to the values obtained for β -phase obtained by stretching from the α-phase material, as analysis through the Vogel-Fulcher-Tamann (VTF) formalism demonstrates (see Fig. 2). Low field ZFC-FC magnetization measurements reveal a remarkable similarity for both pure ferrites. However, room temperature measured hysteresis loops for the pure ferrites and also composites with different percentages of ferrite nanoparticles inside, clearly show superparamagnetic behavior for NiFe2O4/PVDF composites, while the CoFe2O4/PVDF samples develop an hysteresis cycle with coercivity of 0.3 T (see Fig. 3). In all cases the fit of magnetization data at high fields allow us to deduce values of the anisotropy constant Keff, being this of 1.58 x 105 erg/cm3 and 0.12 x 105 erg/cm3 for the CoFe2O4/PVDF and NiFe2O4/PVDF composites, respectively. Finally, The shape of the measured M(H) loops with different directions (in-plane and perpendicular to the plane of the composite) of the applied magnetic field also demonstrates that magnetic particles are randomly oriented within the polymer matrix. This fact is fully supported by the observed linearity in Ms value vs. % ferrite content, hinting for an homogeneous distribution of the ferrite nanoparticles whithin the composites.

References [1]

P Martins, C M Costa, G. Botelho, S Lanceros-Mendez, J.M. Barandiarán and J. Gutiérrez, Materials Chemistry and Physics, 131 (2012) 698-705, and references therein.

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Figures

Figure 1: β-Phase content of the PVDF nanocomposites as a function of CoFe2O4 and NiFe2O4 ferrite content.

Figure 2: VTFH fittings to the β-relaxation for CoFe2O4/PVDF and NiFe2O4/PVDF composites with 20% of ferrite content.

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Figure 3: Room temperature hysteresis loops measured for (left) CoFe2O4/PVDF and (right) NiFe2O4/PVDF nanocomposites with different ferrite concentrations. Hysteresis loops for pure ferrites are also shown.


Detection of the Early Stage of Recombinational DNA Repair by Silicon Nanowire Transistors Marco Chiesa1, Paula P. Cardenas2, Francisco Otón3, Javier Martinez1, Marta Mas-Torrent3, Fernando Garcia1, Juan C. Alonso2, Concepció Rovira3 and Ricardo Garcia1,* 1

Instituto de Microelectrónica de Madrid (IMM-CNM-CSIC), Isaac Newton 8, 28760 Tres Cantos, Madrid, Spain, 2 Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049 Madrid, Spain, Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) and CIBER-BBN, Campus Universitari de Bellaterra, Cerdanyola, 08193 Barcelona, Spain. mchiesa@imm.cnm.csic.es *ricardo.garcia@imm.cnm.csic.es

3

A silicon nanowire-based biosensor has been designed and applied for label-free and ultrasensitive detection of the early stage of recombinational DNA repair by RecA protein.[1] Silicon nanowires transistors were fabricated by atomic force microscopy nanolithography and integrated into a microfluidic environment.[2] The sensor operates by measuring the changes in the resistance of the nanowire as the biomolecular reactions proceed. We show that the nanoelectronic sensor can detect and differentiate several steps in the binding of RecA to a single stranded DNA filament taking place on the nanowireaqueous interface. We report relative changes in the resistance of 3.5% which are related to the interaction of 250 RecA⋅single stranded DNA complexes. Spectroscopy data confirm the presence of the protein-DNA complexes on the functionalized silicon surfaces.

References [1] [2]

Carrasco, B.; Manfredi, C.; Ayora, S.; Alonso, J. C. DNA Repair 7 (2008) 990. Martinez, J.; Martinez, R. V.; Garcia, R. Nano Lett. 8 (2008) 3636.

Figures

Figure 1: (a) Scheme of the device set-up that includes the microfluidic cell. (b) Optical micrograph of the microfluidic channel, gold micro-contacts and nanowire region that bridges the Au contacts. The change in contrast in the channel indicates the regions filled (dark) or unfilled (bright) with the protein solution. (c) AFM image of the device active area (red rectangle of (b)) taken after several biosensing measurements.

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Figure 2: Principle of the biosensor. When the nanowire is covered by a solution with RecA filaments over ssDNA, the resistance reaches a minimum. When a protein impeding the formation of filaments, SsbA, is added to the solution, the resistance of the nanowire partially recovers.

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Magnetization reversal in sub-micrometric Fe-rich glass covered wires A. Chizhik, A. Zhukov, J. Gonzalez Universidad del Pais Vasco, San Sebastián, Spain oleksandr.chyzhyk@ehu.es

Following the tendency of the miniaturization of active elements for magnetic sensors the investigation of the magnetization reversal has been performed in Fe-rich sub-micrometric amorphous wires (nominal composition Fe72.75Co2.25B15Si10). The magnetization reversal has been studied using the magneto-optical Kerr effect (MOKE) magnetometer [1].The longitudinal configuration of MOKE was employed. The intensity of the light, reflected from the surface of microwire, was proportional to the magnetization placed in the plane of the light, i.e. to the axial component of the magnetization. A tiny Cu wire was attached to the sample end in order to apply the axial tensile stress. The torsion stress has been applied during the experiments too. The series of the microwires with different values of geometric ration ρ has been studied (ρ is ratio of metallic nucleus diameter, d, to total microwire diameter, D): sample No1 ρ=0.04, metallic nucleus radius r=400 nm, D=19μm; sample No2 ρ=0.067, r=700 nm, D=21 μm; sample No3 ρ=0.085, r=1000 nm, D=21 μm.

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Figure 1: (a) – MOKE dependence on axial magnetic field (sample No3); (b) dependence of surface coercive field on geometric ration ρ.

It was found that for the microwires of such thin dimensions surface hysteresis loop has a rectangular shape related to magnetic bistability effect (Fig.1a). It confirms the existence of the Surface Large Barkhausen Jump (SLBJ) in sub-micrometric glass covered wires which is explained by the magnetization reversal in a large single surface domain [2]. Fig.1b demonstrates the coercive field (HC) growth with decreasing of the geometric ratio ρ. The highest value of the surface coercive field is observed for the extremely small value of the ratio ρ. Such rising of the switching field has been attributed to the increasing of the strength of internal stresses as increasing the glass coating thickness. The experimental HC dependence on the tensile stress has been plotted as a function of the square root of applied stress σ (Fig. 2a). Good fitting of the experimental points by the linear dependence takes place. The surface bistability effect is related to formation of surface domain wall. The coercive field in the surface like in the volume of the wire is proportional to the energy required to form the domain wall y involved in the bistable process. The surface coercive field is related to the magneto-elastic anisotropy as given by [3]:


where A is the exchange energy constant, λS is saturation magnetostriction constant, σ is applied tensile stress and σr is the internal tensile stress. As it is possible to see, the coercive field must be proportional to σ1/2 for the applied stress σ larger than the internal stress that is observed in the performed experiments.

Figure 2: (a) Tensile stress dependence of coercive filed for sample No 2. (b) Torsion stress dependence of coercive field for sample No 2.

The experimental HC dependence on the torsion stress also has been plotted as a function of the square root of applied stress τ (Fig. 2b). Analysis of the obtained results has been performed following [4] where the appearance of the magneto-elastic anisotropy coming from the applied torsion stress is supposed. In this case the dependence of the coercive field on the torsion stress could be presented as:

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Good fitting of the experimental points by the linear dependence also observed for the torsion stress that permits us to suppose the existence of the “inner core – outer shell” magnetic configuration with radial and surface closure domains in the surface of the studied nano-wires. Therefore, we can conclude that in the extremely thin Fe rich glass covered sub-micrometric wires, the magnetic bistable behavior is observed like in the glass covered wires of micro-scale. The performed analysis of the tensile and torsion stresses transformation of surface hysteresis loop demonstrates that about one order decrease of the wire scale does not abolish the basic effects observed earlier in thicker wires. It permits to reduce considerably the size of basic elements of magnetic sensors and make the next step in the way of sensor miniaturization.

References [1] [2] [3] [4]

J. Gonzalez A. Chizhik, A. Zhukov, J. M. Blanco, Journal of Physics: A, 208 (2011) 502. A. Chizhik, A. Stupakiewicz, A. Maziewski, A. Zhukov, J. Gonzalez, J. M. Blanco, Appl. Phys. Lett., 97 (2010) 012502. L. Kraus, S.N. Kane, M. Vazquez, G. Rivero, E. Fraga, A. Hernando, 1994 J. Appl. Phys. 75 (1994). V. Raposo, J.M. Gallego, M. Vazquez, J. Magn. Magn. Mater., 242–245 (2002) 1435.


Magnetic interactions and interface phenomena on FexAg100-x granular thin films M. L. Fdez-Gubieda1, J. Alonso1, A. García Prieto2 1

Departamento de Electricidad y Electrónica, 2 Departamento Física Aplicada I, Universidad de País Vasco, UPV/EHU, Barrio Sarriena s/n, 48940 Leioa, Spain. malu.gubieda@ehu.es

Magnetic nanostructured thin films present a rich variety of spin arrangements, which depend on, among other factors, the interparticle magnetic interactions. These interactions play a fundamental role in the magnetic behavior of the system and are related to the size, concentration of nanoparticles and the interface between them and the matrix. In order to carry out a thorough study of the role of the interactions, and their evolution with the concentration of nanoparticles, one needs to be especially careful with the selected system. Metallic granular systems, with magnetic nanoparticles embedded in a metallic matrix, are especially suitable to study the role of these interactions since there is no oxide layer surrounding the nanoparticles, which could affect their magnetic behavior, and the sample is stable and can be used repeatedly. Therefore, we have prepared FexAg100-x granular thin films, with Fe-concentration 15 ≤ x ≤ 50, by sputtering deposition technique. Binary FexAg100-x granular thin films are ideal to study these phenomena since Fe and Ag present, a high value of positive alloy formation energy (28 kJ/mol), thereby being highly immiscible. This fact allows obtaining samples consisting of an assembly of Fe nanoparticles embedded in a diamagnetic metallic Ag matrix. X-ray Diffraction, High Resolution Transmission Electron Microscopy and Extended X-ray Absorption Fine Structured spectroscopy have enabled a comprehensive structural description of the system. This arrangement consists of Fe nanoparticles, mostly around 2-3nm in diameter, inside the Ag matrix with grain diameter around 11nm. The magnetic behavior has been characterized both by DC magnetic measurements in SQUID magnetometer. We have found that with increasing the Fe content a change in the collective magnetic behavior of the Fe-Ag thin films is observed, related to a change in the relevance of the different interparticle magnetic interactions that are playing an important role at these concentrations: long-range dipolar and/or RKKY interactions below 30-35 %, and short-ranged strong direct exchange interactions above that threshold. Therefore, it can be considered that around a 30-35 at. % of Fe a magnetic percolation takes place, giving rise to a crossover from a Superspin Glass to a Superferromagnetic behavior [1]. This study has allowed us to propose a magnetic phase diagram presented in figure 1. For comparison, we have also analyzed the effect the interface on the magnetic coupling between Fe nanoparticles. To this end, we have prepared Fe50Ag50 thin films by Pulsed Laser Deposition technique. With this technique we were able to prepare Fe bcc nanoparticles around 2-3nm in diameter surrounded by an amorphous interface, well observed with Transmission electron microscopy and confirmed by EXAFS measurements. Depending on the magnetic state of the interface, we modify the coupling between the magnetic nanoparticles, changing the coercitivity and remanence of the system. If the interface is in the ferromagnetic state, the triggering of interparticle coupling is achieved and the coercive field is small, Hc=7Oe and the normalized remanence is high, Mr/Ms=0.9. By contrast, at temperatures above the Curie temperature of the interface, T>200K, the interface enters in the paramagnetic state and as a consequence the magnetic interaction between nanoparticles is broken down. As a result, the coercitivity of the system increase up to 30Oe and the remanence decrease down to 0.5. In this way, the interface acts as a switch between the Fe nanoparticles [2].

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References [1] [2]

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J. Alonso, M. L. Fdez-Gubieda, J. M. Barandiarán, A. Svalov, L. Fernández Barquín, D. Alba Venero and I. Orue. Phys. Rev. B 82, 054406 (2010) J. Alonso, M. L. Fdez-Gubieda, G. Sarmiento, J. Chaboy, R. Boada, A. García Prieto, D. Haskel, M. A. Laguna-Marco, J. C. Lang, C. Meneghini, L. Fernández Barquín, T. Neisius and I. Orue; IOP Nanotechnology, 23 (2012) 025705


One-Step Fabrication of Multifunctional Core-Shell Nanofibres by Co-Electrospinning Antonio L. Medina-Castillo1, Jorge F. Fernández-Sánchez2, Alberto Fernández-Gutiérrez2 1

NanoMyP®, Nanomateriales y Polímeros S.L. Spin-Off company of the UGR, BIC building Avd. Innovacion 1, 18100, Granada, Spain. 2 Department of Analytical Chemistry, University of Granada Avd. Fuentenueva s/n, 18071 Granada, Spain. amedina@nanomyp.com

Optical sensors represent a useful alternative to electrochemical sensors for monitoring biological parameters such as oxygen and pH. In contrast to their mainly electrochemical counterparts, optical sensors are easy to miniaturize, are cost-effective and can be read out without physical contact. Both pH and O2 monitoring are crucial in many (bio)chemical process. Real-time monitoring and imaging of these parameters in (bio)chemical samples are of high interest in bioengineering, life science and for controlling bioprocesses at the industrial scale. Optical sensor particles represent a very useful tool for real-time monitoring of these parameters. Recently, the concept of optical-sensor particles was enhanced by the incorporation of magnetic properties into their structure [1]. This enables the operator to trap the sensors at a distinct spot and to guide them to a desired position within the measurement setup. During recent years, two-functionalized sensors of nano- or micro-materials have been prepared in one step. Usually, these two functionalities correspond to magnetic susceptibility and an optical-sensing property, i.e. pH or O2. However, no research is available showing that these three functionalities (magnetic susceptibility and optical sensing to O2 and pH) have been simultaneously incorporated into micro- or nano-sensing materials via an easy one-step method. For the successful conjugation of these three functionalities via an easy one-step approach, it is necessary to create two different chemical environments on the same material: a hydrophilic environment to a pH indicator and a hydrophobic environment to an O2 indicator. The magnetic susceptibility could be incorporated in either of these environments, depending on the chemical properties of the magnetic materials used. Bearing in mind these requirements, we conclude that it is difficult to achieve a multifunctional (magnetic, optical sensing to pH and to O2) micro- or nano-material with satisfactory optical features via easy onestep conventional techniques [2] such as miniemulsion-evaporation, precipitation-evaporation, spray-dry, electrospray, emulsion-polymerization, solution-polymerization, or miniemulsion-polymerization, among others. In the present study, we has been developed a novel methodology to design a multifunctional sensor phase, via easy one-step. This new multifunctional sensor phase is based on core-shell fibre mats made by co-electrospinning. The core-shell fibre mats have three different functionalities: they are magnetic and optically sensitive to pH and O2. On the one hand, the shell is formed by a fluorescent pH-sensitive copolymer which was previously synthesized and characterized [3]. On the other hand, the core is a suspension formed by magnetic nanoparticles in a solution made up by a lipophilic indicator dye (oxygen indicator; PtOEP) and, poly-methyl methacrylate, in THF. The magnetic nanoparticles were prepared by encapsulation of magnetite within a cross-linked polymeric matrix (MMA-co-EDMA). The morphology of the well-organized core-shell fibres were characterized by high resolution scanning electron microcopy (HRSEM), transmission electron microcopy (TEM), and confocal laser microscopy (see Fig. 1).

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The luminescent properties of core-shell fibre mats were analysed and successfully used for monitoring simultaneously pH (from 6 to 8) and O2, showing complete reversibility, high sensitivity (i.e. Ksv=7.07 bar-1 for determining O2 in aqueous media), high magnetic susceptibility and short response times (see Fig 2). Acknowledgements: The authors express their thanks to the Spanish Ministry of Education (FPU grant reference AP2006-01144 and Project CTQ2008-01394) and the Regional Government of Andalusia (Excellence projects P07-FQM-02738 and P07-FQM-02625). In addition, they thank the company Yflow S.L. for their collaboration in the development of the sensing films by co-electrospinning. References [1] [2] [3]

P. Chojnacki, G. Mistlberger, I. Klimant, Angew. Chem.-Int. Edt. 46, 2007, 8850. A. L. Medina-Castillo, G. Mistlberger, J. F. Fernandez-Sanchez, A. Segura-Carretero, I. Klimant, A. Fernandez-Gutierrez, Macromolecules. 43, 2010, 55. [A. L. Medina-Castillo, J. F. Fernandez-Sanchez, A. Segura-Carretero, A. Fernandez-Gutierrez , J. Mater. Chem. 21, 2011, 6742.

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Figure 1: A) HRSEM of the coaxial fibres B) TEM of fibers in which the magnetite can be observed; and C) confocal microscopy images of the coaxial fibres when they are excited at 488 and 530 nm. C)

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Polarization Properties of the Scattered Radiation by Silicon Nanoparticles in the Infrared Braulio García-Cámara1*, Raquel Gómez-Medina2, Francisco González1, Juan José Sáenz2, Manuel Nieto-Vesperinas3 and Fernando Moreno1 1

Grupo de Óptica. Departamento de Física Aplicada. Universidad de Cantabria, 39005, Santander, Spain 2 Departamento de Física de la Materia Condensada e Instituto Nicolás Cabrera. Universidad de Autónoma de Madrid, 28049, Madrid, Spain 3 Departament of Theory and Simulation of Materials. Instituto de Ciencia de los Materiales de Madrid (CSIC), 28049, Madrid, Spain *braugarcia@gmail.com

The main properties of the light scattered by isolated particles or particle systems contain much information about the scatterer: size, shape and optical properties. Although most of research analyzes scattered intensity properties (spectrum, scattering patterns, etc), polarization parameters can be also very interesting to obtain this information [1]. In particular, in a previous research [2], we showed that the spectral evolution of the linear polarization degree measured at a scattering angle of 90º [PL(90º)] is sensitive to deviations from a pure dipolar behavior (size, anisotropy, multiple scattering). Concerning isolated and isotropic particles, this means that if the size parameter, x=2πR/λ, is much smaller than 1 and multipolar effects are absent, PL(90º) remains equal to 1. If particle size grows and/or multipolar contributions become important, significant changes are detected in PL(90º). In a similar way, we stated that this parameter can also identify magnetic response in light scattering by dipole-like particles [3]. Thus, PL(90º) get negative values when the magnetic character of the particle dominates, while it remains positive if the dominate behavior is electric. Recently, it has been shown that nanoparticles (R~200nm), made of silicon or germanium, present both electric- and magnetic-like resonant behaviors in the near-infrared range [4, 5]. Taking this into account, the objective of this contribution is to analyze the polarimetric properties of scattered radiation by silicon nanoparticles in the infrared (1-2 μm). Applying our knowledge developed in [3], we will analyze the electric and magnetic response of this kind of nanoparticles and the influence of their size by means of the spectral evolution of the linear polarization degree at right-angle scattering configuration (RASC). This analysis will allow us to relate polarimetric and energetic properties of light scattering of this realistic system. In Figure 1 we show the spectral evolution of the considered polarimetric parameter [PL(90º)] for a silicon nanoparticle with R=230 nm in the interval (1-2μm). Size effects become non-negligible in the considered range. For this reason, we have considered multipolar contributions. In particular, the first four Mie terms (electric and magnetic, dipolar and quadrupolar ones) are plotted. As in [3], when the electric dipolar character (a1) dominates, PL is clearly positive and tends to the ideal value of 1. As the magnetic dipolar conduct (b1) becomes more important, PL tends to decrease and it is negative when the magnetic dipolar resonance is excited. For shorter wavelengths, the size/wavelength ration induces that quadrupolar terms are comparable to the dipolar ones and even a magnetic quadrupolar mode (b2) is excited. This produces a complex behavior of PL(90º) that will be explained. In summary, in this research we have analyzed the spectral evolution of the linear polarization degree at right angle scattering configuration, PL(90º), of silicon particles (R~200nm) in the IR. We can conclude that its measurement can be a complementary tool to the conventional analysis of either the scattering or extinction spectra. PL(90º) can reveal and distinguish electric and magnetic responses of the scattering system. In addition, in this research we have considered multipolar contributions, in other to study how they contribute to the polarimetric parameter.

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Acknowledgments This research has been supported by Spanish MICINN (Ministerio de Ciencia e Innovacion) under project FIS2010-21984, Consolider NanoLight (CSD2007-00046), FIS2009-13430-C01C02 and FIS2007-60158, the EU NMP3-SL-2008-214107- Nanomagma, as well as by the Comunidad de Madrid Microseres-CM (S2009/TIC-1476). Work by B.G-C. and R.G.-M were supported by the University of Cantabria Postdoctoral Fellopwship and the MICINN ”Juan de la Cierva” Fellowship, respectively. References [1] [2] [3] [4] [5]

M.I. Mishchenko and L.D. Travis, pp. 159-175, F. Moreno and F. González, Eds. (Springer-Verlag, 2000). B. Setién, P. Albella, J.M. Saiz, F. González and F. Moreno, New J. Phys. 12 (2010), 103031. B. García-Cámara, F. González and F. Moreno, Opt. Lett. 35 (2010), 4084-4086. R. Gómez-Medina, B. García-Cámara, I. Suárez-Lacalle, F. González, F. Moreno, M. NietoVesperinas and J.J. Sáenz, J. Nanophoton. 5 (2011), 053512 A. García-Etxarri, R. Gómez-Medina, L.S. Froufe-Pérez, C.López, L. Chantada, F. Scheffold, J. Aizpurua, M. Nieto-Vesperinas and J.J. Sáenz, Opt. Express 19 (2011), 4815-4826.

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Figure 1: Spectral evolution of PL(90º) of a silicon particle (R = 230nm). The first four contributions of the Mie expansion to the extinction efficiency are also shown.


Highly-confined spin-polarized two-dimensional electron gas in SrTiO3/SrRuO3 superlattices P. Garcia-Fernandez1, M. Verissimo-Alves1, D.I. Bilc2, P. Ghosez2 and J. Junquera1 1

Departamento de Ciencias de la Tierra y Fisica de la Materia Condensada, Universidad de Cantabria, Cantabria Campus Internacional, Avenida de los Castros s/n, 39005, Santander, Spain 2 Physique Theorique des Materiaux, Universite de Liege, Allee du 6 aout 17 (B5), B-4000, Sart Tilman, Belgium garciapa@unican.es

We report first principles characterization of the structural and electronic properties of (SrTiO3)5/(SrRuO3)1 superlattices. We show that the system exhibits a spin-polarized two-dimensional electron gas extremely confined to the 4d orbitals of Ru in the SrRuO3 layer. Every interface in the superlattice behaves as minority-spin half-metal ferromagnet, with a magnetic moment of Îź = 2.0 ÎźB/SrRuO3 unit. The shape of the electronic density of states, half metallicity and magnetism are explained in terms of a simplified tightbinding model, considering only the t2g orbitals plus (i) the bi-dimensionality of the system, and (ii) strong electron correlations. As a result we find that the half-filled degenerate Ru(dxz,dyz) bands participating at the Fermi energy have strong bonds only along one-direction and so display characteristics of even lower dimensionality. Finally we study the consequences of this particular electronic structure over the transport properties, particularly thermoelectric ones, by using Boltzmann's transport theory.

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High magneto-optical performance in metal-dielectric magnetoplasmonic nanodisks Antonio García-Martín, Juan Carlos Banthí, David Meneses, Fernando García, María Ujué González, Alfonso Cebollada, and Gaspar Armelles IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain a.garcia.martin@csic.es

The term magnetoplasmon, or magnetoplasma surface wave, was first introduced in the early 70’s, motivated by a renovated interest in surface plasmons in metals and degenerate semiconductors [1,2]. Nowadays, the phenomenology associated to systems where plasmonic and MO properties coexist has become an active area of investigation. The so called magneto-plasmonic systems have opened new routes for the development for example of higher performance gas and biosensing platforms [3,4] as well as the exploitation of non-reciprocal effects [5] in devices with potential applications in the telecomunications area. In magnetoplasmonic structures, magnetic and plasmonic properties are intertwined, allowing for example plasmonic properties to become tunable upon application of a magnetic field (active plasmonics) [6], or the MO effects to be largely increased by plasmon resonance excitation, as a consequence of the enhancement of the electromagnetic (EM) field in the MO active component of the structure [7]. In this last case, the study of the enhanced MO activity in structures with subwavelength dimensions is especially interesting since the properties of these systems upon plasmon resonance excitation bring as a consequence an enhanced EM field in its interior, and more interestingly in the region where the MO active component is present. Unfortunately, it is not straightforward to experimentally determine the intensity of the EM field inside a nanostructure. Here we show (Fig.1) how the EM profile related to the localized surface plasmon resonance can be probed locally inside the nanostructure by measuring the MO activity of the system as a function of the position a MO active probe (a Co nanolayer) [8]. At this stage, optimizing the EM field distribution within the structure by maximizing it in the MO components region while simultaneously minimizing it in all the other, non MO active, lossy components, will allow for the development of novel systems with even larger MO activity with reduced optical absorption, becoming an alternative to state of the art dielectric MO materials, like garnets[9]. We will show how the insertion of a dielectric layer in Au/Co/Au magnetoplasmonic nanodisks induces an EM field redistribution in such a way to concentrate it in the regions of interest of the nanostructure. Figure 2 shows as an example experimental and theoretical optical extinction and MO activity for the system with the SiO2 layer attached to the upper Au layer and for the fully metallic structure. The metallodielectric system exhibits large MO activity and low optical extinction in the high wavelength range (around 780 nm). It will be demonstrated how this is due to the specific EM field redistribution at this wavelength, controlled by the insertion of the dielectric layer. Acknowledgements The authors acknowledge funding support from the EU (NMP3-SL-2008-214107Nanomagma), the Spanish MICINN (“FUNCOAT” CONSOLIDER INGENIO 2010 CSD2008-00023, MAGPLAS MAT2008-06765-C02-01/NAN and PLASMAR MAT2010-10123-E) and the Comunidad de Madrid (“NANOBIOMAGNET”, S2009/MAT-1726 and “MICROSERES-CM”, S2009/ TIC-1476, and JAE Doc fellowship for D. Meneses-Rodríguez).

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References [1] [2] [3] [4] [5] [6] [7] [8] [9]

K.W.Chiu and J.J.Quinn, Physical Review 5 (1972) 4707. E.D.Palik et al., Physics Letters 45A (1973) 143. B.Sepúlveda et al., Opt. Lett. 31 (2006) 1085. M.G.Manera et al., Journal of Materials Chemistry 21 (2011) 16049. J.B.González-Díaz et al., Phys. Rev. B 76 (2007) 153402. V.V.Temnov et al., Nature Photonics, 4 (2010) 107. G.Armelles et al., J. Opt. A: Pure Appl. Opt. 11 (2009) 114023. D. Meneses-Rodríguez, et al., Small 7, (2011) 3317. J.C. Banthi, et al., Adv. Mater., (in press) (2011).

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Figure 1: (a) Sketch of the fully metallic nanodisks (b) Maximum magneto-optical activity as a function of the Co position for fully metallic nanodisks (c) Electromagnetic field distribution inside a AuCoAu nanodisk.

Figure 2: Left: Experimental and theoretical optical extinction and MO activity for the structure with the SiO2 layer attached to the upper Au layer (continuous lines) and for the fully metallic structure (dashed lines). Right: Sketch of the fabricated structures, and representative AFM image of one of them


Electric and Magnetic Dipolar Response of Small Dielectric Particles: Angle-Suppressed Scattering and Optical Forces R. Gómez-Medina1, B. García-Cámara2, I. Suárez-Lacalle1, L. S. Froufe-Pérez1, F. González2, F. Moreno2, M. Nieto-Vesperinas3, and J. J. Sáenz1 1

Departamento de Física de la Materia Condensada and Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, 28049 Madrid, Spain. Grupo de Óptica, Departamento de Física Aplicada, Universidad Cantabria, 39005 Santander, Spain. 3 Instituto de Ciencia de Materiales de Madrid, C.S.I.C.,Campus de Cantoblanco, 28049 Madrid, Spain. r.gomezmedina@uam.es 2

In the presence of both electric and magnetic properties, the scattering characteristics of a small object present markedly differences with respect to pure electric or magnetic responses. Even in the simplest case of small or of dipolar scatterers, remarkable scattering effects of magnetodielectric particles were theoretically established by Kerker et al. [1] concerning suppression or minimization of either forward or backward scattering. Intriguing applications in scattering cancellation and cloaking together with the unusual properties of the optical forces on magnetodielectric particles [2] have renewed interest in the field. The striking characteristics of the scattering diagram of small (Rayleigh) magnetodielectric particles [1, 3] were obtained assuming arbitrary values of electric permittivity and magnetic permeability. Nevertheless, no concrete example of such particles that might present those interesting properties in the visible or infrared regions had been proposed. Here, we show [4] that submicron dielectric spheres present dipolar magnetic and electric responses (see Fig. 1), characterized by their respective first-order Mie coefficient, in the near infrared, in such a way that either of them can be selected by choosing the illumination wavelength. Moreover, we will see that Si or Ge spheres constitute such a previously quested real example of dipolar particle with either electric and/or magnetic response, of consequences both for their emitted intensity [5, 6] and behavior under electromagnetic forces [2, 5, 7]. Specifically the exact scattering diagram, computed from the full Mie expansion, of submicron Si and Ge particles in the infrared will be shown to be consistent with the expected result for dipolar electric and magnetic scattering (see Fig. 2). Finally, we will show that the force is a simple combination of conservative and non-conservative steady forces that can rectify the flow of magnetodielectric particles. In a vortex lattice the electric-magnetic dipolar interaction can spin the particles either in or out of the whirls sites leading to trapping or diffusion (see Fig. 3). References [1] [2] [3] [4] [5] [6] [7]

M. Kerker, D. S. Wang, and C. L. Giles, “Electromagnetic scattering by magnetic spheres”, J. Opt. Soc. Am. 73, (1983) 765-767. M. Nieto-Vesperinas, J. J. Sáenz, R. Gómez-Medina and L. Chantada, “Time-averaged total force on a dipolar sphere in an electromagnetic field”, Opt. Express 18, 11428-11443 (2910). B. García-Camara, F. Moreno, F. Gonzalez and J. M. Saiz, “Exception for the zero-forwardscattering theory”, J. Opt. Soc. Am. A 25, (2008) 2875-2878. A. García-Etxarri, et al , “Strong magnetic response of Silicon nanoparticles in the infrared”, Opt. Express 19, 4815-4826 (2011). M. Nieto-Vesperinas, R. Gómez-Medina, and J. J. Sáenz, “Angle-Suppressed Scattering and Optical Forces on Submicron Dielectric Particles”, J. Opt. Soc. Am. A 28, 54-60 (2011). R. Gómez-Medina, et al., “Electric and magnetic dipolar response of Germanium spheres: Interference effects, scattering anisotropy and optical forces”, J. Nanophoton. 5, (2011) 053512. R. Gómez-Medina, M. Nieto-Vesperinas and J. J. Sáenz, “Nonconservative electric and magnetic optical forces on submicron dielectric particles”, Phys. Rev. A, 83, 033825 (2011).

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Figures Figure 1: Scattering cross section map of a nonabsorbing Mie sphere as a function of the refractive index m and the y parameter, y = mka. Green areas correspond to parameter ranges where the magnetic dipole contribution dominates the total scattering cross section, while red areas represent regions where the electric dipole contribution is dominating. The remaining blue saturated areas are dominated by higher order multipoles. (Adapted from Ref.[4]).

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Figure 2: Scattering diagrams for the 240nm Ge nanoparticle (εp =16 and μp =1) at λ=2193 and λ=1823 nm, (first and second GK conditions, respectively). Both polarizations, with the incident electric field parallel (P polarization) or normal (S polarization) to the scattering plane are considered. Notice that while the backward intensity drops to zero at the first GK condition wavelength, at the second condition, although the most of the intensity goes backward, the scattering diagram presents a very small peak in the forward direction. (Adapted from Ref. [6]).

Figure 3: Nonconservative forces on a Si sphere of radius a=230nm placed at the intersection region of two standing waves for a wavelength λ=1725nm slightly above (red-shifted) the magnetic dipolar resonance. Arrows in (a) and (b) point along the total force lines. (a) Contour maps of the modulus of the normalized total force. (b) Contour maps of the normalized electric field intensity. The symbols sketch the force fields at several positions: □ corresponds to saddle points and Δ corresponds to unstable equilibrium (zero-force) positions, respectively. (Adapted from Ref.[7]).


Electrospinning of Biopolymers: Applications Jose Maria Lagaron, Amparo Lopez-Rubio Novel Materials and Nanotechnology Group, IATA, CSIC, Avda. Agustín Escardino 7, 46980, Burjassot, Spain; lagaron@iata.csic.es

Looking genuinely at nature, nanofibers often serve as a basic platform where either organic or inorganic components are built upon. For instance, cellulose nanofibers would represent the building block in plants while collagen nanofibers in the animal body. The fiber structure exhibits, from a structural point of view, the certain ability to transmit forces along its length and, thus, reducing the amount of materials required. While strong enough for their designed purpose, nanofibers have the added advantage of giving high porosity to the natural supports which allows faster diffusion of chemicals to the inner structure. To follow this extraordinary nature’s design, a process that is able to fabricate fiber nanostructures from a variety of materials and mixtures is an indispensable pre-requisite. Control of the nanofibers arrangement is also necessary to optimize such structural requirements. Electrospinning is a physical process used for the formation of ultrathin fibers by subjecting a polymer solution to high electric fields. At a critical high voltage (5-25 kV), the polymer solution droplet at the tip of the needle distorts and forms a Taylor cone to be ejected as a charged polymer jet. This stretches and is accelerated by the electrical field towards a grounded and oppositely-charged collector. As the electrospun jet travels through the electrical field, the solvent completely evaporates while the entanglements of the polymer chains prevent it from breaking up. This results in the ultrathin polymer fibers deposition on a metallic collector to habitually assemble the fibers as non-woven mats. Since the electrospinning is a continuous process, fibers when winded can be as long as several metres or even kilometres. The formed fibers are not only ultrathin and relatively large in length but also fully interconnected to form a three-dimensional network. The current paper will highlight some recent advances carried out within our research group in which various applications of the high voltage spinning processing technique making use of biopolymers and biopolymeric blends will be reviewed [1-10]. References [1] [2] [3] [4]

Martínez-Sanz, M., Olsson, R.T., Lopez-Rubio, A., Lagaron, J.M., 2010, Cellulose, pp. 1 Torres-Giner, S., Lagaron, J.M., 2010 Journal of Applied Polymer Science 118 (2), pp. 778 Torres-Giner, S., Martinez-Abad, A., Ocio, M.J., Lagaron, J.M. 2010 Journal of Food Science 75 (6), pp. N69 Olsson, R.T., Kraemer, R., López-Rubio, A., Torres-Giner, S., Ocio, M.J., Lagarón, J.M., 2010 Macromolecules 43 (9), pp. 4201 [5] López-Rubio, A., Sanchez, E., Sanz, Y., Lagaron, J.M. 2009, Biomacromolecules 10 (10), pp. 2823 [6] Fernandez, A., Torres-Giner, S., Lagaron, J.M. 2009 Food Hydrocolloids 23 (5), pp. 1427 [7] Torres-Giner, S., Ocio, M.J., Lagaron, J.M. 2009 Carbohydrate Polymers 77 (2), pp. 261 [8] Torres-Giner, S., Ocio, M.J., Lagaron, J.M. 2008 Engineering in Life Sciences 8 (3), pp. 303 [9] Torres-Giner, S., Gimenez, E., Lagaron, J.M., 2008 Food Hydrocolloids 22 (4), pp. 601 [10] Torres-Giner, S.; Gimeno-Alcañiz, J.V.; Ocio, M.J.; Lagaron, J.M. ACS Appl. Mater. Interfaces 2009, 1, 218 Acknowledgements Contract grant sponsor: MICINN, MAT2009-14533-C02-01 and EUI2008-00182 and the EU FP7 IP ECOBIOCAP, FREESBE and NEWBONE

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Hydrogen storage on Palladium doped nanoporous carbons María J. López1, Iván Cabria1, Cecilia Bores1, Silvia Fraile2, Julio A. Alonso1 1

2

Dpto. de Física Teórica, Universidad de Valladolid, 47011 Valladolid, Spain Dpto. de Física Aplicada-LATUV, Universidad de Valladolid, 47011 Valladolid, Spain maria.lopez@fta.uva.es

Nanoporous carbons are among the best candidates for hydrogen storage. Recently we have revealed the structure of nanoporous carbons derived from carbides [1]. A structure of open pores emerges and the carbon network forming the pore walls consists in one atom thick graphene layers interconnected among them and exhibiting exposed graphene edges. The storage of hydrogen is driven by the adsorption of molecular hydrogen on the pore walls of the material. However the performance of these materials at room temperature and moderate pressures is quite limited. Some promising experiments suggest that Palladium nanoparticles might enhance the storage of hydrogen in porous carbons by surface reactions [2], although the mechanism is not well known. To gain some insight on the role played by palladium in the storage of hydrogen, we have investigated the adsorption and formation of small palladium clusters on a graphene surface, and the adsorption and dissociation of molecular hydrogen on the adsorbed palladium clusters. Density functional calculations show that Pd atoms have a strong tendency to form clusters [3]. Supported three-dimensional clusters are more stable than planar ones, and the transition from planar to three-dimensional structure occurs early as a function of cluster size, namely at Pd4. This feature is a consequence of the strong Pd-Pd interaction. We have also investigated the adsorption and the dissociation of molecular hydrogen on the deposited Pd clusters as a function of cluster size, from a single Pd adatom to the Pd6 cluster. The mechanisms for the molecular adsorption of the hydrogen molecule and for the possible subsequent dissociation are discussed, as well as the activation barriers for dissociation. According to the present simulations, a single adsorbed Pd atom does not dissociate the hydrogen molecule. Starting with deposited Pd2, the clusters dissociate the molecule with no barriers or with small barriers (see Fig. 1). The dissociation and adsorption of molecular hydrogen on the edges of graphene nanoribbons is also investigated to gain insight on the contribution of the exposed graphene edges of the nanoporous carbons to the reversible hydrogen storage capacity of these materials. Our Density functional calculations show that molecular hydrogen dissociates and adsorbs atomically at the ribbon edges without activation barrier. The adsorption energies are quite large, between 2.5 and 5.7 eV, what indicates that the ribbon edges are very reactive and will be saturated with hydrogen whenever available. However, under mild conditions of pressure and temperature hydrogen cannot be desorbed from the edges and, therefore, the edges do not contribute to the reversible storage capacity of the material.

References [1] [2] [3]

M.J. López, I. Cabria, and J.A. Alonso, J. Chem. Phys., 135 (2011) 104706. C.I. Contescu, et al., J. Phys. Chem. C 113 (2009) 5886; A. Lueking and R.T. Yang, Appl. Catal. A 265 (2004) 259. I. Cabria, M.J. López, and J.A. Alonso, Phys. Rev. B 81 (2010) 035403.

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Figures

Figure 1: Adsorbed (left) and dissociated (right) hydrogen molecule on an octahedral Pd6 cluster supported on a graphene surface.

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Exploiting the biomimetic properties of multiwall carbon nanotubes in cancer treatment Mónica L. Fanarraga1, Juan C. Villegas2, Lidia Rodriguez-Fernandez3, Rafael Valiente4, Jesús Antonio Gonzalez5 1

Departamento de Biología Molecular, Universidad de Cantabria-IFIMAV, 39011, Santander. Spain. fanarrag@unican.es 2 Departamento de Anatomía y Biología Celular, Universidad de Cantabria-IFIMAV, 39011, Santander. Spain. 3 SERMET, Universidad de Cantabria, Avda. de Los Castros s/n 39005, Santander, Spain 4 Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Cantabria, Avda. de Los Castros s/n, 39005 Santander, Spain 5 MALTA-Consolider Team, CITIMAC, Facultad de Ciencias, Universidad de Cantabria, Avda. de Los Castros s/n, 39005 Santander, Spain jesusantonio.gonzalez@unican.es

Carbon nanotubes (CNTs) have long been blamed for their toxicity leading cell transformation and cancer[1-6]. When examined in detail, these adverse effects are basically the consequence of the interaction of these fibbers with the naturally occurring intracellular nano-filaments, mostly DNA molecules (2 nm diameter) [6,7] and the cytoskeletal polymers, that include actin (6 nm) [8], microtubules (25 nm) [9,10] and intermediate filaments (8-10 nm) [2]. All these intracellular nano-fibbers display different lengths and can form bundles susceptible to interact with CNTs. But microtubules in particular, are highly analogous to CNTs. They are indeed biological nanotubes constituted of 13 protein polymers arranged in a circle that self assembles, display a high resiliency and have a high aspect ratio. Our work unravels the molecular interaction between multiwall CNTs and microtubules in human cancer cells, demonstrating how these nanomaterials can interfere with microtubule function required for cell viability, locomotion and proliferation, leading to cancer cell destruction. These findings could lead to the development of a revolutionary generation of nano-drugs based on the biomimetic properties of multiwall CNTs that could completely transform traditional chemotherapy. References [1] [2]

[3]

[4] [5]

[6]

[7] [8]

Krug, H. F.; Wick, P. Nanotoxicology: An interdisciplinary challenge, Angew. Chem. Int. Ed. Engl. 2011. 50, 1260-1278 Safi, M.; Yan, M.; Guedeau-Boudeville, M. A.; Conjeaud, H.: Garnier-Thibaud, V.; Boggetto, N.; Baeza-Squiban, A.; Niedergang, F.; Averbeck, D.; Berret, J. F. Interactions between magnetic nanowires and living cells: uptake, toxicity, and degradation. ACS Nano 2011. 5, 5354-64. Di Giorgio, M. L.; Di Bucchianico, S.; Ragnelli, A. M.; Aimola, P.; Santucci, S.; Poma, A. Effects of single and multi walled CNTs on macrophages: cyto and genotoxicity and electron microscopy. Mutant. Res. 2011. 722, 20-31. Gonzalez, L.; Decordier, I.; Kirsch-Volders, M. Induction of chromosome malsegregation by nanomaterials. Biochem. Soc. Trans. 2010. 38, 1691-1697. Sargent, L. M.; Shvedova, A. A.; Hubbs, A. F.; Salisbury, J. L.; Benkovic, S. A.; Kashon, M. L.; Lowry D. T.; Murray, A. R.; Kisin, E. R.; Friend, S.; McKinstry, K. T.; Battelli, L.; Reynolds, S. H. Induction of aneuploidy by single-walled carbon nanotubes. Environ. Mol. Mutagen. 2009. 50, 708-717. Cveticanin, J.; Joksic, G.; Leskovac, A.; Petrovic, S.; Sobot, A. V.; Neskovic, O. Using CNTs to induce micronuclei and double strand breaks of the DNA in human cells. Nanotechnology 2010. 21, 015102. Li, X.; Peng, Y.; Qu, X. CNTs selective destabilization. of duplex and triplex DNA, inducing B-A transition in solution. Nucleic Acids Res. 2006. 34, 3670–3676. Holt, B. D.; Short, P. A.; Rape, A. D.; Wang, Y. L.; Islam, M. F.; Dahl, K. N. Carbon nanotubes reorganize actin structures in cells and ex vivo. ACS Nano 2010. 4. 4872-4878.

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[9]

Pampaloni, F.; Florin, E. L. Microtubule architecture: inspiration for novel carbon nanotubebased biomimetic materials. Trends Biotechnol. 2008. 26. 302-310. [10] Dinu, C. Z.; Bale, S. S.; Zhu, G.; Dordick, J. S. Tubulin encapsulation of CNTs into functional hybrid assemblies. Small 2009. 5, 310-315. Figures Figure 1: HeLa cells incorporate MWCNTs. (left) TEM of a HeLa cell showing several bundles of MWCNTs (red arrows) within the cytoplasm. (inset) A microtubule running in parallel (white arrows) to the bundle is shown. (rigt) Raman scattering experiments performed intracellular (red) and extratracellular (black) MWCNT. The Raman spectrum representative for the MWCNT aggregates shows a number of well characterized MWCNT resonances.

Figure 2: MWCNTs interfere with cancer cell proliferation. Confocal microscopy image of a HeLa cell undergoing anaphase where an abnormally high density of midzone microtubules is observed (white arrow). This is accompanied by chromosomal bridges (blue arrow) characteristic of clastogenic events (inset, empty arrow). Acentrosomal ectopical microtubule nucleation is observed (red arrows).

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Figure 3: Molecular MWCNT-Microtubule interaction model. Microtubules are 25 nm diameter nano-tubes build of tubulin. Typically 13 protofilaments associate in a circle to form the microtubule. In contrast to CNTs, microtubules highly continuously undergo assembly/disassembly cycles. The less dynamic end is labeled with the (-) sign, the most dynamic end, indicated with the (+) sign, continuously undergoes rapid assembly/ disassembly cycles. (botom) MWCNTs share many structural similarities with microtubules. Inside the cells both types of filaments associate into bundles that increase microtubule resistance to depolymerization, behaving as tubulin scaffolds, and promoting microtubule nucleation and growth


Plasmonic Fano resonances become single-particle F. López-Tejeira, R. Paniagua-Domínguez, R. Rodríguez-Oliveros, J. A. Sánchez-Gil Instituto de Estructura de la Materia (IEM-CSIC), Consejo Superior de Investigaciones Científicas Serrano 121, 28006 Madrid, Spain flt@iem.cfmac.csic.es

Experimental and theoretical investigations have shown that metallic nanorods act as standing-wave resonators for localized plasmon resonances in the optical regime [1, 2], thus exhibiting geometrical halfwavelength resonances with spectral positions depending mainly on the length of the rods. This particular type of so-called “optical nanoantennas” have raised the prospect of significant improvements in fields such as photodetection [3], field-enhanced spectroscopy [2, 4], or control of emission direction in singlemolecule light sources [5]. Generally speaking, most of device-oriented studies are focused on nanoantennas operating at the dipolelike resonance. However, structures with a high aspect ratio may support additional resonances that have usually been the subject of a more fundamental research work. Hence, several authors have already elucidated the scaling properties of high-order longitudinal modes, as well as their dependence on shape, size, orientation and dielectric environment by means of diverse approaches and techniques. Nevertheless, a relevant issue has yet to be addressed for multi-resonant nanoantennas, that is the emergence of asymmetric line profiles in single particle extinction or scattering spectra. Interestingly, such a feature seems to go almost unnoticed for the nanoplasmonics community, despite being apparent in some previous reports. In Figure 1 we present the calculated scattering efficiency for a single silver spheroid surrounded by glass (ɛd= 2.25) under the assumption that incident field is p-polarized and impinges perpendicular to the long side of the rod. Different curves correspond to increasing values of total length L within the [100,400] nm range, whereas the polar diameter D is set to 30 nm for all calculations. As can be seen, the position of resonances increases linearly within the L range. For L/D>5, the peaks arising from resonances with n=1 and n=3 are clearly apparent, as it is the asymmetry of the line shape between them. This suggests the interaction of adjacent resonances to be compatible with a Fano-like interference model, where the lower resonance plays the role of continuum in canonical Fano line shape. In this work [6], we show that these asymmetric line profiles can be easily understood in terms of the socalled Fano-like interference between localized plasmon resonances that has been recently reported for a variety of coupled metal nanoparticles [7,8]. Being more precise, we present a simplified analytical model that describes spectral features of a single-arm nanoantenna in terms of Fano-like interference. Contrary to the common assumption that interference does not play any role in total scattering or extinction of a single metallic particle, we find a good agreement with numerical results, which are attained through the separation of variables (SVM) [9], finite element (FEM) [10], and surface integral equation (SIEM) methods [11,12]. Furthermore, we make use of explicit analytical expressions for light scattering by spheroids to conclude that not only spectral but also spatial overlap (i.e. non-orthogonality) between interacting modes underlies the emergence of such single-rod resonances, for which evidence is found in a variety of singleparticle nanoantennas, namely nanospheroids, nanorods with either flat or hemispherical ends and also infinitely long rectangular nanowires. The research presented in this contribution is supported by the Spanish “Ministerio de Ciencia e Innovación” (projects Consolider-Ingenio EMET CSD2008-00066 and NANOPLAS FIS2009-11264) and the

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“Comunidad de Madrid” (MICROSERES network S2009/TIC-1476). R. Paniagua-Domínguez acknowledges support from CSIC through a JAE-Pre grant. References [1] [2] [3] [4] [5] [6]

Mühlschlegel, P.; Eisler, H.-J.; Martin, O. J. F.; Hecht, B.; Pohl, D.W., Science 308 (2005) 1607. Muskens, O. L.; Giannini, V.; Sanchez-Gil, J. A.; Gómez Rivas, J., Nano Lett. 7 (2007) 2871. Knight, M. W.; Sobhani, H.; Nordlander, P.; Halas, N. J., Science 332 (2011) 702. Ming, T.; Zhao, L.; Yang, Z.; Chen, H.; Sun, L.; Wang, J.; Yan, C., Nano Lett. 9 (2009) 3896. Taminiau, T. H.; Stefani, F. D.; Segerink, F. B.; van Hulst, N. F., Nat. Photonics 2 (2008) 234. López-Tejeira, F.; Paniagua-Domínguez, R.; Rodríguez-Oliveros, R.; Sánchez-Gil, J. A., to be published in New. J. Phys., preliminary version at arXiv: 1111.3551 [7] Miroshnichenko, A.; Flach, S.; Kivshar, Y. Rev. Mod. Phys. 82 (2010) 2257. [8] Luk’yanchuk, B.; Zheludev, N. I.; Maier, S. A.; Halas, N. J.; Nordlander, P.; Giessen, H.; Chong, C. T., Nat. Mater. 9 (2010) 707. [9] Voshchinnikov, N. V.; Farafonov, V. G., Astrophys. Space Sci. 204 (1993) 19. [10] COMSOL Multiphysics finite element software, version 4.2: RF module. [11] Giannini, V.; Sánchez-Gil, J. A., J. Opt. Soc. Am. A 24 (2007) 2822. [12] Rodríguez-Oliveros, R.; Sánchez-Gil, J. A., Opt. Express 19 (2011) 12208. Figures

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Figure 1: Calculated scattering efficiency as a function of wavelength for a single Ag spheroid (top right) surrounded by glass (ɛd = 2:25). Incident field is p-polarized and impinges perpendicular to the rotation axis of the spheroid. Different curves correspond to increasing values of L, whereas D is set to 30 nm for all calculations. Right: Nanorod geometries for which evidence of Fano-like interference is found in [6].


NanoBasque Strategy: Basque Country´s strategic bid for nanoscience, micro and nanotechnologies Cristina Oyón/Amaia Martínez nanoBasque Agency - SPRI, Paseo Mikeletegi 53, 20009 Donostia-San Sebastian, SPAIN nanobasque@spri.es

Over the past fifteen years, nanoscience, micro and nanotechnologies have become a major global trend, in which public and private entities have, estimately, invested more than 20 billion euros. These are certainly disciplines that enable radical innovation, providing new applications for many sectors of high growth potential. But their successful implementation requires a new model of relationships in which companies, research centers and universities collaborate more closely to provide a qualitative and quantitative step ahead to compete globally with new products and higher value-added processes. The Basque Country has shown a strong commitment towards this innovative model of relationships and places nanoscience, micro and nanotechnology as a catalyst for this great change, being aware that it is time to respond decisively to a huge opportunity. The nanoBasque Strategy aims to create a new business, technology and scientific model in the Basque Country enabled by nanoscience, micro and nanotechnologies. A model that is results-oriented, diversified, open and connected, robust, cohesive, competitive and sustainable. The incorporation of nanoscience, micro and nanotechnologies as a strategic area for industrial diversification within the Basque Country's science, technology and innovation policies is performed with two main goals: to exploit the huge application potential of these technologies in almost every industrial sector in the Basque Country, especially the automotive industry, aeronautics, energy, electronics, telecommunications, machine-tool, steel, metallurgy and household appliances, and to promote the creation of new technology based companies that make take full advantage of applications based on such technologies. The first roll-out phase of this strategy supposed laying its foundations with a significant public investment in knowledge generation, basically by the creation of the cooperative research centres CIC microGUNE and CIC nanoGUNE. The increasingly important participation of companies together with science/technology agents in R+D projects in these fields, and the launch of a support system for the development of new business projects, with the creation of a nanoincubator, are a clear response from the business development and dinamization actions performed in the deployment of the strategy. There are currently sixtyfive companies working in the field of micro- and/or nanotechnology in the Basque Country, although the number of companies participating in R&D projects in these areas is well over a hundred. Seventeen of these companies are already marketing micro and/or nanotechnologybased products or processes and this figure is expected to double in the next two years. The cross-over nature of these technologies is reflected in the identification of companies from more than 12 different industrial sectors, the majority of which have high growth perspectives. Thus, the activity in intermediate sectors such as steel, metallurgy and metallic products, or final sectors such as the automotive industry, health and pharmaceuticals, should be highlighted.

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Less than the 8% of these companies are self-sufficient when it comes to develope their micro and nano activity, this meaning that close collaboration with science/technology supply agents is essential. NanoBasque strategy is structured around three main axis of activity: knowledge generation, business development and dinamization of the sector, activities that will be developed in four strategic areas understood as key concepts of strategy deployment:

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Materials: they are a key factor in the competitiveness of the Basque business base and it is in this area where the incorporation of nanoscience and nanotechnologies may allow an increase of the technological intensity and diversification into higher value products.



Convergence micro-nano-bio: The convergence in these areas offers in the field of health and quality of life a perfect opportunity to put into value the skills developed in the Basque Country in recent years and the generation of market applications through the knowledge generated.



Enabling tools and techniques: the continued training of our scientific-technological system in tools and techniques that allow the characterization, synthesis, analysis, design, modeling and manufacturing is key to allow the introduction of micro and nano in our companies.



Safety: the emergence of any new technique requires an assessment of the risks and benefits involved in its operation and that is why the analysis of the impact of nanotechnology during its life cycle from production and processing, use and end of its useful life it is necessary for a proper use and requires a specific follow-up regulatory action and communication to society.


Synthesis of gold, silver and gold-silver nanostructures from organometallic precursors, plasmonic, bactericidal and catalytic properties. Miguel Monge, Julián Crespo, Jorge García-Barrasa, José M. López-de-Luzuriaga, M. Elena Olmos Universidad de La Rioja, Departamento de Química. Grupo de Síntesis Química de La Rioja, UA-CSIC. Complejo Científico Tecnológico. Madre de Dios 51. E-26004 Logroño (Spain) miguel.monge@unirioja.es

The synthesis and study of new noble metal nanostructures is one of the hottest research topics in the last years due to broad range of properties that can be reached at the nanometer size scale. This include plasmonic, bactericidal or catalytic properties and they can be tuned by varying the physical size, shape and composition of the nanostructures.[1,2] By the use of our experience in gold and silver organometallic chemistry we have developed a new approach for the synthesis of gold, silver and gold-silver nanostructures that is the decomposition under mild conditions of perhalophenyl organometallic precursors of these metals, in the presence of several types of organic stabilizers, leading to colored stable colloidal solutions. Monometallic silver and gold nanoparticles have been synthesized by the decomposition of the organometallic complex [Ag(C6F5)] or [Au(C6F5)(tht)] (tht = tetrahydrothiophene), respectively. The presence of long alkyl chain ligands such as amines, thiols or carboxylic acids or the presence of polymers like poly(vinyl)pyrrolidone (PVP), cellulose acetate (CA) or, even, SiO2-PVP nanocomposites has allowed us the stabilization of small size nanoparticles. We have studied both the surface plasmon resonance displayed by colloidal solutions of these nanoparticles, as well as the bactericidal or catalytic properties of some of them.[3-5] The synthesis of gold-silver nanostructures has been carried out using the heterometallic complex [Au2Ag2(C6F5)4(Et2O)2]n that is the unique source of both metals in the decomposition reaction. We have obtained alloyed gold-silver nanoparticles of different sizes and shapes depending on the reaction conditions and stabilizing agents. The use of nuclear magnetic resonance in solution and the characterization of the nanoparticles through their surface plasmon resonance bands allowed us to study the mechanism of formation of these bimetallic nanoparticles.

References [1] [2] [3] [4] [5]

C. N. R. Rao, A. Müller, A. K. Cheetham (Eds). The Chemistry of Nanomaterials. Synthesis, Properties and Applications Vols. 1 and 2. (Wiley-VCH Verlag, Weinheim, 2004). C. N. R. Rao, A. Müller, A. K. Cheetham (Eds). Nanomaterials Chemistry. Recent Developments and New Directions. (Wiley-VCH Verlag, Weinheim, 2007). E. J Fernández, J. García-Barrasa, A. Laguna, J. M López-de-Luzuriaga, M. Monge, C. Torres Nanotechnology 19 (2008) 185602 (6pp). J. García-Barrasa, J. M López-de-Luzuriaga, M. Monge, K. Soulantika, G. Viau J. Nanopart. Res. 13 (2011) 791-801. J. García-Barrasa, J. M López-de-Luzuriaga, M. Monge Cent. Eur. J. Chem. 9 (2011) 7-19.

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Figures

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Figure 1: Some examples of metal nanostructures synthesized from organometallic precursors: (a) PVP stabilized Ag nanoparticles; (b) hexadecylamine stabilized Au-Ag nanoparticles; (c) SiO2-PVP stabilized Ag nanoparticles; (d) Ag nanoparticles at the surface of SiO2 nanoparticles; (e) hexadecylamine stabilized Au-Ag hollow nanoprisms and (f) oleic acid stabilized Au-Ag ultrathin nanowires.


Low temperature optical emission of WZ InAs NWs M. Möller1, M. M. de Lima, Jr. 1, A. Cantarero1, T. Chiaramonte2, M. A. Cotta2, F. Iikawa2 1

Instituto de Ciencia de los Materiales, Universidad de Valencia, E-46071, Valencia, Spain 2 Instituto de Física Gleb Wataghin, UNICAMP, CEP-13083-859, Campinas-SP, Brazil Mauricio.Morais@uv.es

Semiconductor nanowires (NWs) are attracting considerable attention due to their potential application in advanced nanophotonic devices. In addition, it has been shown that III-V NWs, such as InP, GaAs and InAs, can exhibit wurtzite (WZ) crystal structure in contrast to the cubic zincblende (ZB) phase of their bulk materials. The change in crystal structure alters the optical and electronic properties of the material and results in different fundamental physical parameters such as the band gap energy, exciton binding energy and phonon energies. As a consequence of the novelty brought by the NW growth, even for GaAs, which is among the most well-known materials, an ample controversy regarding the band gap energy of the WZ structure still exists. In the the case of InAs much less information is available. The known theoretical studies predict a WZ band gap 40 – 66 meV higher than the one of the ZB phase.[1,2] Trägårdh et al. have predicted a WZ band gap of 0.54eV by extrapolating fitted photocurrent measurements on InAs1−xPx NWs[3] and Bao et al. observed a value of 0.52 eV in two-dimensionallike WZ structures.[4] In this contribution, we have investigated the low temperature emission of WZ InAs NWs using PL spectroscopy. A detailed study of the power and temperature dependence of two InAs NW samples, grown at different temperatures, is presented. The InAs NWs have been grown by the VLS method in a chemical beam epitaxy system using gold nanoparticles as catalysts on an (100) GaAs substrate. The growth temperatures were 420ºC and 450ºC for sample A and B, respectively. The structure of the NWs has been studied by transmission electron microscopy (TEM) and reveals a predominant WZ structure, grown along the [0001] direction, with presence of ZB stripes. The NWs of both samples have diameters in the range of 40 – 200 nm and lengths of 2 – 15 μm. PL measurements were carried out on ensembles of NWs of sample A and B using a pulsed Ti-sapphire laser (pulse width of ∼3 ps and repetition of ∼80MHz) as exciting source syntonized at 760 nm and focused on a spot of approximately 1 mm2. The sample was cooled with a cold-finger He cryostat with CaF2 optical windows, where the sample temperature was varied from 5 to 100 K. In Fig. 1, the PL spectra from sample A [Fig. 1(a)] and sample B [Fig. 1(b)] measured for different excitation powers at 5K are presented. Two optical emission bands are observed in both samples. The low energy emission band (LEB) does not shift with increasing excitation power while we detect a pronounced blue-shift for the high energy emission band (HEB). In both samples, LEB dominates at low excitation power and HEB dominates for high power, suggesting a saturation effect which is common for an impurity-like recombination process at high excitation power, generally observed in bulk. The PL spectra at different positions on both samples were fitted with two Gaussian functions and their PL peak energies are depicted in Figs. 2(a) and (b). The HEB peak position blue-shifts approximately 15 meV as the excitation power raises from 10 to 500 meV. This large energy shift is a behavior usually observed in quantum wells (QWs) with type II band alignment which is attributed to the band bending induced by the carrier accumulation at the interfaces and the band filling effect. Similar blue shifts have been observed in InP[5] and GaAs[6] NWs containing WZ and ZB phases, where type II interfaces between these phases were present. In our InAs NWs, in fact, two phases along the wire axis are observed in TEM images forming QWs as depicted in the schematic diagram in Fig. 1(c). It has been predicted theoretically that InAs ZB/WZ superlattices have a type-II band alignment.[1] At low excitation powers, electrons in the ZB sections recombine with the holes in the WZ sections [transition 1 in Fig. 1(c)] leading to an emission below both, the ZB and WZ, band gap energies. When the excitation power is increased, state filling (transition 2) of electrons in the ZB section results in a blue-shift and broadening of the HEB [see Fig. 2(a)]. Thus, we attribute the HEB to the QW related emission. Our NWs present a diameter much larger than the effective Bohr radius and we assume that the lateral quantum confinement is negligible.

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In Fig. 3(a) we present the temperature dependent PL spectra measured for a fixed intermediate excitation power (50mW) for sample B. In Fig. 3(b) we display the PL spectra for different excitation powers measured at 100K for sample B. The corresponding PL peak energies for the HEB as a function of temperature for a fixed intermediate excitation power (50mW) and as a function of different excitation powers measured at 100K are depicted in Figs. 3(c) and (d) for sample A (squares) and sample B (circles), respectively. A clear blue-shift with increasing temperature is observed. This behavior, which is opposite to the usual reduction of the band gap of semiconductors with increasing temperature, may be attributed to a temperature trigged band filling effect on the ZB phase, similar to that discussed for high excitation powers. In addition, rising the excitation power at 100K [see Fig. 3(b) and (d)] further blue-shifts the emission band. We associate this to the appearance of the band-toband transition in the WZ phase. When the excitation power is increased at 100 K, this band becomes more evident and starts to dominate. This results in an overall blue-shift that is much larger than those observed in Fig. 2(a) attributed to the QW related emission. In fact, if we assume that at high temperatures the electrons in the QWs could be thermally excited to the WZ phase barrier, the recombination in the WZ phase [transition 3 in Fig. 1(c)] should increase while the QW related emission reduces. From the peak positions shown in Fig. 3(d), we estimate the fundamental gap of WZ InAs at 100K to be 0.453 ± 0.010 eV. Assuming that the temperature dependence of the band gap of InAs is the same for the WZ and ZB phases, the 5K band gap energy can be estimated as: EWZ,5K = EWZ,100K + (EZB,5K− EZB,100K) = 0.453meV + 0.015meV = 0.468meV. This value is 53meV higher than that of the ZB structure and is in very good agreement with the available theoretical works which predict a 40 – 66meV higher value for the WZ structure and it is close to the experimental data of 0.52meV and 0.54meV mentioned before.

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References [1] M. Murayama, T. Nakayama, Phys. Rev. B, 49 (1994) 4710. [2] A. De, C. E. Pryor, Phys. Rev. B, 81 (2010) 155210. [3] J. Trägårdh, A. I. Persson, J. B. Wagner, D. Hessmann, L. Samuelson, J. Appl. Phys., 101 (2007) 123701. [4] J. Bao, D. C. Bell, F. Capasso, N. Erdman, D. Wei, L. Fröberg, T. Mårtensson, and L. Samuelson, Adv. Mater., 21 (2009) 3654. [5] K. Pemasiri, M. Montazeri, R. Gass, L. M. Smith, H. E. Jackson, J. Yarrison-Rice, S. Paiman, Q. Gao, H. H. Tan, C. Jagadish, X. Zhang, and J. Zou, Nano Lett., 9 (2009) 648. [6] T. B. Hoang, A. F. Moses, L. Ahtapodov, H. Zhou, D. L. Dheeraj, A. T. J. van Helvoort, B.-O. Fimland, and H. Weman, Nano Lett., 10 (2010) 2927. Figures

Figure 1: The PL spectra for different excitation powers measured at 5K from (a) sample A and (b) sample B, respectively. (c) Schematic diagram of the valence band (VB) and the conduction band (CB) of the WZ InAs NWs with ZB sections.

Figure 2: PL peak energies of the (a) high energy emission band (HEB) and (b) the low energy emission band (LEB) as a function of the excitation power for sample A (squares) and sample B (circles). Integrated PL intensities of (c) the HEB and (d) the LEB for both samples.

Figure 3: PL spectra from sample B measured at different temperatures. (b) PL spectra from sample B measured at 100K for different excitation powers. (c) PL peak energies of the HEB of sample A (squares) and sample B (circles) as a function of temperature. (d) PL peak energies at 100K as a function of excitation power.


Thermometry: a novel functionality for magnetic nanoparticles Carlos D.S. Brites1, Patricia Lima1, Rafael Piñol2, Nuno J.O. Silva1, Vitor S. Amaral1, Angel Millán2, Luis D. Carlos1*, Fernando Palacio2* 1

Department of Physics, CICECO, University of Aveiro, Campus Universitário de Santiago, 3810–193 Aveiro, Portugal lcarlos@ua.pt 2 Instituto de Ciencia de Materiales de Aragón. CSIC - Universidad de Zaragoza, 50009 Zaragoza, Spain. palacio@unizar.es

Temperature is a fundamental thermodynamic variable, the measurement of which is crucial in countless scientific investigations and technological developments, accounting at present for 75%–80% of the sensor market throughout the world. The traditional liquid-filled and bimetallic thermometers, the thermocouples, the pyrometers and the thermistors are generally not suitable for temperature measurements at scales below 10 μm. This intrinsic limitation has encouraged the development of new non-contact accurate thermometers with micrometric and nanometric precision, a challenging research topic increasingly hankered for. This work describes absolute temperature sensing/mapping − in the 10-350 K range and submicrometer spatial resolution − using magne…c siloxane-based hybrid nanoparticles (NPs) co-doped with Eu3+ and Tb3+ tris(β-diketonate) chelates. This unique luminescent self-referencing nanothermometer has been recently reported by us [1,2]. The developed thermometer has up to 4.9%⋅K-1 temperature sensitivity (1.5 times larger than the highest value reported previously) and it exhibits high photostability for long-term use. The variation of the Eu3+/Tb3+ ratio affords tunability to the temperature working range as shown in Figure 1. Alternatively, tunability is also accomplished by changing the host matrix, thus modifying the interaction between the Ln3+ and the host matrix energy levels. The nanothermometer is a versatile material which can be processed in different forms adapted to the desired application, e.g. a thick film coating an integrated circuit trough which we obtain a high resolution 2-D temperature mapping depicted in Fig. 2. The presentation will also include an account on current state of the art of thermometry at the nanoscale and in particular of lanthanide-based luminescent molecular thermometry.

References [1]

[2]

a) C.D.S. Brites, P.P. Lima, N.J.O. Silva, A. Millán, V.S. Amaral, F. Palacio, L.D. Carlos, Adv. Mater., 2010, 22, 4499; b) F. Palacio, A. Millán, N. J. Silva, L. D. Carlos, V. Amaral, P. P. Lima, C. D. S. Brites, Spain Patent P200930367, 2009. C.D.S. Brites, P.P. Lima, N.J.O. Silva, A. Millán, V.S. Amaral, F. Palacio and L.D. Carlos, New J. Chem., 2011, 35, 1177.

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Figures

Figure 1: a) Photoluminescence of the molecular thermometer inserted in g Fe2O3@TEOS/APTES magnetic nanoparticles excited at 357 nm and recorded between 14 and 300K: 1 and 2 are the 5D4  7F6,5 emissions of Tb3+ and 3, 4 and 5 are the 5 7 D0  F2-4 ones of Eu3+; b) CIE chromaticity diagram showing the temperature dependence of the (x,y) color coordinates of the nanoparticulate thermometer.

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Figure 2: Temperature profiles obtained with the molecular thermometer processed as a coating paint onto a variable resistance (blue circles, the size corresponds to the temperature uncertainly of 0.5 degree) as compared with the measurements performed using an IR camera (red squares).


Functionalization of electrode surfaces with three-dimensional networks of electropolymerized gold nanoparticles for biosensor design J.M. Pingarrón,1 R. Villalonga,1 P. Díez,1 P. Yáñez-Sedeño,1 M. Eguílaz,1 S. Casado,2 1

Department of Analytical Chemistry, Faculty of Chemistry, Complutense University of Madrid, 28040-Madrid, Spain 2 IMDEA Nanosciences, Cantoblanco University Campus, 28049-Madrid, Spain pingarro@quim.ucm.es

Nowaday, the construction of new electrochemical biosensors with improved bioanalytical performance and robustness is directly linked to the development of novel strategies for tailor-made design of electrode surfaces. Such strategies should provide electrical interfaces with nano- or microsized treedimensional topology that allow the successful and stable immobilisation of the biomolecules without affecting their biological function, but also favouring the fast and efficient occurrence of the electrochemical processes involved in the analytical reaction on such interface. During last recent years, nanosized materials have been exhaustively employed in the modification of electrodes for biosensing purposes [1]. In general, the development of methodologies for nanostructuring electrode surfaces with such purpose should consider the following points: i) the type of surface to be modified, ii) the nanomaterial to be used, iii) other compounds/materials that could be also employed, iv) the physical/chemical method for surface modification, v) the biomolecule to be immobilized and the method to do that, and vi) the electrochemical reaction to take place on the functionalized electrode surface. The present work describes an original approach for nanostructuring electrodes surfaces, based on the electrochemical preparation of a three-dimensional matrix of gold nanoparticles through the formation of bisaniline-cross-linked networks. These nanostructured networks were further employed as supports for the immobilization of redox enzymes for the construction of electrochemical biosensors. The rationale of our strategy is based on the design and synthesis of small polyfunctionalized gold nanoparticles (2.5-5.7 nm diameter), specifically capped with three different thiol derivatives: paminothiophenol as polymerizable unit, 2-mercaptoethanesulfonic acid as solubilising moiety and a third thiol ligand which should be employed for enzyme immobilization (Fig. 1). In the present work, we used as third capping ligands the following thiol derivatives: A) 3-Mercaptophenyl boronic acid for the oriented immobilization of the glycoenzyme horseradish peroxidase [2]. B) Cysteamine core polyamidoamine (PAMAM) G-4 dendron for the multipoint covalent immobilization of tyrosinase using glutaraldehyde as cross-linking agent [3]. C) 1-Adamantanethiol for the supramolecular immobilization of a cyclodextrin-xanthine oxidase neoglycoconjugate through host-guest interactions. The nanoparticles capped with the ligands described in A) and B) were electropolymerized on gold electrode surfaces, previously coated with a monolayer of p-aminothiophenol. Horseradish peroxidase was further immobilized on the boronic acid-modified nanostructured matrix (Fig. 1A), yielding a wired enzyme electrode which was employed to construct a third generation amperometric biosensor toward H2O2. This biosensor showed excellent analytical characteristics, with a linear behavior in the range between 5 µM and 1.1 mM of H2O2, a high sensitivity of 498 µA·M-1·cm-2, and a low detection limit of 1.5 µM.

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On the other hand, tyrosinase was covalently cross-linked on the electrode surfaces covered with the PAMAM dendron-coated Au nanoparticle networks (Fig. 1B). The biosensor constructed with these electrodes showed a very low detection limit of 20 nM toward cathecol, with a linear response from 50 nM to 10 µM of this analyte and a sensitivity of 1.94 A·M-1·cm-2. Au nanoparticles coated with 1-adamantanethiol moieties were finally electropolymerized on glassy carbon electrodes previously coated with single walled carbon nanotubes (Fig. 1C). This nanostructured surface was used for the supramolecular immobilization of a β-cyclodextrin-xanthine oxidase neoglycoconjugate, for the design of a biosensor device toward xanthine. This biosensor showed an excellent electroanalytical behavior, with a low detection limit of 30 nM and a sensitivity of 543 mA·M1 ·cm-2. All enzyme biosensors prepared also showed high reproducibility, selectivity and stability. Taking into account these results achieved in this research, it can be predicted that the use of a bisaniline-cross-linked nanostructured network of metal nanoparticles constitutes an excellent nanoelectrochemical strategy to construct scaffolds for the successful immobilization of redox enzymes in order to prepare amperometric biosensors with improved analytical characteristics. References [1]

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[2] [3]

J. Wang, Analyst 130 (2005), 421; J. Wang, Electroanalysis 17 (2005), 7; C.S.S.R. Kumar, Nanomaterials for biosensors. Nanotechnologies for the life sciences (2006), 8, Wiley-VCH, Weinheim; S. Li, J. Singh, H. Li, I.A. Banerjee, Biosensor Nanomaterials, 2011, Wiley-VCH, Weinheim. R. Villalonga, P. Díez, P. Yáñez-Sedeño, J.M. Pingarrón, Electrochim. Acta 56 (2011), 4672. R. Villalonga, P. Díez, S. Casado, M. Eguílaz, P. Yáñez-Sedeño, J.M. Pingarrón, Analyst 137 (2012), 342.

Figures

Figure 1: Preparation of the electrodes modified with electropolymerized Au nanoparticles-based networks for the detection of H2O2 (A), cathecol (B) y xanthine (C)


Optical enhancement effect in metal-organic nanohybrids integrated with whispering-galerymode Microcavities Y.P. Rakovich1,2, D. Savateeva1, D. Melnikau2, A. Chuvilin2,3, R. Hillenbrand2,3 1

Centro de Fisica de Materiales (CSIC-UPV/EHU), Paseo Manuel de Lardizabal 5, Donostia –San Sebastian, Spain 2 IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain 3 CIC nanoGUNE Consolider, Tolosa Hiribidea, 76, 20018 Donostia-San Sebastian, Spain yury.rakovich@ehu.es

We report on enhanced optical effects in novel type of hybrid structures that combine high-Q spherical microcavities with Ag nanoparticles and organic dye molecules in a J-aggregate state. A layer by-layer deposition technique provided controllable coating of the latex microspheres with a shell of close-packed Ag nanoparticles and J-nano-aggregates. Colloidal silver nanoparticles of 30 nm average size were synthesized by the conventional citrate reduction method. The formation of J-aggregates was promoted by electrostatic interaction between positively charged dye molecules and negatively charged polystyrenesulfonate, and confirmed using UV-VIS absorbance spectroscopy. A periodic structure of narrow peaks was observed in the photoluminescence spectrum of the Jnanoaggregates (Fig.1), arising from the coupling between the emission of J-nanoaggregates and the whispering gallery modes (WGMs) of the microcavity, which are which are electromagnetic waves that circulate and are strongly confined within the microcavity [1,2]. The most striking result of our study is the observation of polarization sensitive mode damping caused by re-absorption of J-nanoaggregate emission (Fig.1). This effect manifests itself in dominating emission from the transverse magnetic (TM) modes in the spectral region of J-nanoaggregates absorption band where the transverse electric (TE) modes are strongly suppressed. In contrast, the TE modes totally dominate emission spectrum in the region where absorption is negligible. Polarization sensitive mode damping observed in the spectral region of high J-aggregate absorption can be used for suppression of unwanted modes in high Q optical whispering gallery resonators. Our experiments also revealed that WGMs alone can be responsible for enhancement of optical responses from J-nanoaggregates. At the same time, coherent coupling between localized plasmons of the metalic nanoparticles and the exciton in molecular aggregates results in strongly plasmon-enhanced Raman signal. SEM analysis of surface of microcavity integrated with Ag nanoparticles revealed presence of fractal-like metallic aggregates which serve as so called “hot spots“. These spots are nanometer-scale spatial regions of high local electric field, and cause not only significant enhancement of Raman scattering, but also strong PL inhancement and shortening in PL lifetime of J-nanoaggregates observed in our lifetime-imaging experiments. Owing to the concerted action of “photonic hot spots” (the locally enhanced electric fields due to WGM resonances in microcavities) and “plasmonic hot spots” in the Ag aggregates, we observe strongly increased photoluminescence intensity, intensified spontaneous emission rate and enhanced Raman scattering from the J-nanoaggregates (Fig.1). Coupling of the plasmonic fields supported by metal nanoparticles and excitonic states of J-aggregates to microcavity local fields might be employed to manipulate the density and quality of modes and to control spontaneous emission rate in coupled hybrid system.

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References [1] [2]

.P. Rakovich, J.F. Donegan Laser & Photonics Reviews, 4 (2010) 179 Dzmitry Melnikau, Diana Savateeva, Andrey Chuvilin,Rainer Hillenbrand and Yury P. Rakovich Optics Express, 19 (2011) 22280.

Figures

Figure 1: Room-temperature PL spectrum from single MF microsphere covered by monolayer of J-nanoaggregates. Inserts show the results of mode identification using Mie scattering theory. Green and red squares indicate TM and TE modes of first order, respectively. Blue squares indicate TE modes of second order.

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Figure 2: Micro-photoluminescence spectrum of single WGM microcavity with hybrid shell. Insert shows SEM image (a) and confocal photoluminescence image of microcavity/shell structure.


Efficient organic distributed feedback lasers with active films imprinted by thermal nanoimprint lithography A. Retolaza1, I. Alonso1*, D. Otaduy1, A. Juarros1, S. Merino1, M.G. Ramirez2, P.G. Boj2, V. Navarro-Fuster2, I. Vragovic2, J.M. Villalvilla2, J.A. Quintana2, M.A. Diaz-Garcia2 1

Micro and Nano Manufacture Unit, Tekniker-IK4, Avda. Otaola 20, 20600, Eibar, Spain Instituto Universitario de Materiales de Alicante, Universidad de Alicante, 03080 Alicante, Spain *Dept. of Applied Physics II, University of the Basque Country, Paseo de la Universidad 7, 01006, Vitoria, Spain aretolaza@tekniker.es 2

Organic solid-state lasers (OSLs) have been a subject of intense research for many years [1] mainly due to the various advantages of organic materials, such as easy processability, chemical versatility, wavelength tunability and low cost. Among the various types of resonators used in the field of OSLs, distributed feedback (DFB) structures are probably the most extensively studied. As compared to other types of lasers, DFBs present several advantages, such as easy deposition of the organic film, low thresholds, single mode emission and no need of mirrors. In addition, DFBs have potential for new applications in the field of biosensing and chemical sensing, that are currently receiving a great deal of attention [2,3]. Among the methods generally used for grating engraving, nanoimprint lithography (NIL) [4] is one of the most promising technologies, even for future industrial applications, due to its high throughput, high resolution (sub-10 nm) and low cost. From the materials point of view, a wide variety of materials has been used to fabricate the active layers of organic DFBs [1]. Among them, our group has focused in the last years in polystyrene (PS) films doped with perylenediimide derivatives (PDIs) [5], mainly due to their excellent thermal and photostability properties, as well as their high photoluminescence quantum efficiencies. In addition, these materials are particularly interesting in the field of data communications based on polymer optical fibers because they emit at wavelengths around 570 nm, inside the second low-loss transmission window in poly(methylmethacrylate). We recently reported [6] low-threshold and highly photostable (under ambient conditions) DFB lasers, based on PDI-doped films, in which the DFB gratings were fabricated by thermalNIL on a resist and then transferred to the substrate (SiO2). In view of the good performance of these lasers, we thought about possible ways to further improve their performance. A very attractive strategy consists in engraving the DFB gratings directly on the active material, instead of on the substrate, in order to simplify the fabrication process and therefore reduce the cost of the devices. In this presentation we report on the fabrication and characterization, under optical pump, of organic DFB lasers based on PS films doped with a PDI derivative (PDI-C6, Figure 1a) as active material [7]. The use of thermal-NIL to imprint the gratings directly on the active film (see scheme of the device geometry in Figure 1b) has allowed, as opposed to room temperature or solvent-assisted techniques, high grating quality and excellent modulation depth (Figures 1c and 1d). In addition, the process is very simple (only one step) with no need of etching methods to transfer them to the substrate. It is also remarkable that the hightemperature treatment (155ºC for 900 s) used in the NIL process does not negatively affect the thermal stability and the optical properties of the active films. The emission wavelength of the devices was tuned between 565 and 580 nm by film thickness variation (Figure 2) and results were successfully modeled by considering an average effective index (“Model average neff”) or an average thickness of the active film “Model h+(d/2)”. These devices combine a simple and low-cost preparation method with good laser characteristics, i.e. thresholds of 1 µJ/pulse, single-mode emission with linewidths below 0.2 nm and photostability half-lives of ∼105 pump pulses under ambient conditions. In comparison to more standard DFBs with gratings on the substrate, their fabrication is much easier, while they show a similar laser performance.

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Acknowledgements This work has been funded by the “Ministerio de Ciencia e Innovación” and the European Community (FEDER) through the grant MAT2008-06648-C02. It was also partially supported by a CSIC fellowship within the program JAE. References [1] [2] [3] [4] [5] [6] [7]

D.W. Samuel, G.A. Turnbull, Chem. Rev., 107 (2007) 1272. M. Lu, S.S. Choi, C.J. Wagner, J.G. Eden, B.T. Cunningham, Appl. Phys. Lett., 92 (2008) 261502. M.B. Christiansen, J.M. Lopacinska, M.H. Jakobsen, N.A. Mortensen, M. Dufva, A. Kristensen, Opt. Express, 17 (2009) 2722. S.Y. Chou, P.R. Krauss, P.J. Renstrom, Appl. Phys. Lett. 67 (1995) 3114. E.M. Calzado, J.M. Villalvilla, P.G. Boj, J.A. Quintana, R. Gómez, J.L. Segura, M.A. Díaz-García, J. Phys. Chem., C111 (2007) 13595. V. Navarro-Fuster, E.M. Calado, P.G. Boj, J.A. Quintana, J.M. Villalvilla, M.A. Díaz-Gracía, V. Trabadelo, A. Juarros, A. Retolaza, S. Merino, Appl. Phys. Lett., 97, (2010) 171104. M.G. Ramirez, P.G. Boj, V. Navarro-Fuster, I. Vragovic, J.M. Villalvilla, I. Alonso, V. Trabadelo, Santos Merino, M.A. Díaz-García, Opt. Express, 19 (2011) 22443.

Figures

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Figure 1: (a) Chemical structure of PDI-C6; (b) Schematic of the DFB device (Λ = 368 nm, d = 260 nm, h = 320-890 nm), (c) SEM image and d) AFM profile of the grating engraved on the active film.

Figure 2: Laser wavelength of DFB devices with active films of different thickness h. Symbols: Experimental data; Thick full line: “Model h+(d/2)”; Dashed line: “Model average neff”; Thin full line: “Model h”.


Light Depolarization in Nanosphere-Dimers by Incoherent Mixing of Mueller Matrices J. M. Sanz1, P. Albella2, J. M. Saiz1, F. Moreno1 and F. González1 1

Grupo de Óptica-Dpto. Fis. Aplicada, Universidad de Cantabria, 39005, Santander, Spain 2 CIC Nanogune, Avda. de Tolosa 76, 20018, San Sebastian, Spain sanzjm@unican.es

In this work, we report on the influence that mixing basic configurations has on the depolarization of the light scattered by two coupled nanospheres. Both the Discrete Dipole Approximation (DDA) and The TMatrix method have been used as intermediate tools to calculate the scattering matrices of coupling metallic nanospheres. When the polar decomposition (PD) is applied to the mixed Mueller matrix (MM), the principal decomposition parameters can be obtained and depolarization turns up. Principal depolarization parameters are sensitive to the gap between nanospheres. This study can be of interest in applications where depolarization has to be avoided. Gas sensing or colloid analysis techniques are two examples of such applications. System Geometry and Numerical Method The scattering system we analyze consists on two silver spheres (n=0,135+3,988i, λ=633nm) of radius r=0.1λ, and with gap distances ranging from 0.1λ to 0.8λ. We have considered three different geometries (X, Y and Z geometry, corresponding to Figs.1a, 1b and 1c, respectively), all illuminated by a monochromatic plane wave of λ=633nm. We numerically obtain the elements of the MM by using DDA [1] and T-Matrix [2]. These computational procedures are suitable for studying scattering and absorption of EM radiation in this kind of electromagnetic systems [3, 4]. The MMs obtained from these procedures have been post-processed in all cases with an algorithm that performs the PD [5]. After testing the purity of the matrices [6], it was found that in the cases analyzed, the MMs obtained for single states were pure. This means that the system does not produce any depolarization. However, depolarization -as incoherent process- could be expressed as a linear combination of pure contributions [6]. In a first approach, we suppose that identically contribution of each pure state (pondered sum of the MMs obtained for X, Y and Z geometries) could lead to depolarization. This procedure can be understood in terms of a randomly contribution from two spherical nanoparticles places along X, Y or Z axis. The system matrix can be decomposed as M4x4= MΔ·MR·MD, where MΔ, the depolarization matrix, is the Identity 4x4 in pure states case, MR is the retardance matrix and MD is the diattenuation matrix. Due to the symmetry properties, and as a result of the PD, we can decompose our problem in an equivalent system composed by an ideal diattenuator aligned with the scattering plane, MD(t), with the fast axis of a lineal retarder, MR(δ), and with the principal axis of a linear depolarizer, MΔ (d1,d2,d3). Examining in detail the polarimetric properties of our system and making use of the PD, we can describe the behavior of our system by just considering from three to six independent parameters: the total system transmittance (M11), the transmission along one of the diattenuator axes (t), the phase shift introduced by the retarder (δ) and, in the case of non-pure systems, the principal depolarization parameters (d1,d2 and d3). Once the meaning of the PD parameters is well understood, this polarimetric method provides us with a handy tool to approach the analysis of the system [7]. Results and Conclusions Principal PD parameters of pure geometries are shown in Fig. 2 a), b) and c), while diattenuation and retardance parameters of a MMs mixing are shown in Fig. 2 d). It is observed that in mixed (non-pure) cases interaction-dominant contributions are smoothed and, although qualitatively the interaction effects remain, quantitatively changes occur. These changes could be analyzed from the depolarization point of

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view. In fact, we can observe depolarization contribution in Fig. 3: When principal depolarization parameters (di) decrease, depolarization increases. Furthermore, depolarization by mixing pure states contribution increases when gap decreases. We are now working in increasing the number of random states (not only X, Y, and Z geometries), so this theoretical approach could be involved with real experimental situations by associating both mean free path in a nanoparticles sample with the gap distance between nanospheres and depolarization with incoherent addition of states due to any type of movement (Brownian, convection flow, etc.). Polarimetric measures in gas sensing, aerosols or colloidal solutions are issues that could be sensitive to depolarization in the terms outlined in this paper. Acknowledgements This research has been supported by the Ministry of Education of Spain under project FIS2010-21984. The authors thankfully acknowledge the computer resources provided by the RES node at University of Cantabria. References [1] [2] [3] [4] [5] [6] [7]

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B. T. Draine, P. J. Flatau, User Guide for the Discrete Dipole Approximation Code DDSCAT 6.1, 2004. URL http://arxiv.org/abs/astro-ph/0409262v2 M. I. Mishchenko, L. D. Travis and D. W. Mackowski, JQSRT, 55 (1996) 535-575. P. Albella, F. Moreno, J. M. Saiz, F. González, Optics Express 15 (11) (2007) 6857-6867. B. Setién, P. Albella, J. M. Saiz, F. González and F. Moreno, New J. Phys. 12 (2010) 103031. J.M. Sanz, P. Albella, F. Moreno, J. M. Saiz and F. González, JQSRT 110 (2009) 1369–1374. J. J. Gil, Eur. Phys. J. of Appl. Phys. 40 (2007) 1-47. J.M. Sanz, J. M. Saiz, F. González, and F. Moreno, Appl. Opt. 50 (21) (2011) 3781–3788.

Figures

Figure 1: Dimer Scattering Geometries

Figure 2: PD Principal Parameters vs. Scatt. Angle for Gap=0,1λ: a), b) and c) Pure Geometries, d) Pondered Mixing Geometries.

Figure 3: Mixing MMs Principal Depolarization Parameters vs. Scatt. Angle: a) Gap=0,1λ, b) Gap=0,2λ c) Gap=0,8λ.


Electronic Structure of Graphene V. M. Silkin, E.V. Chulkov, P.M. Echenique Donostia International Physics Center (DIPC), P. de Manuel Lardizabal 4, 20018 San Sebastián, Basque Country, Spain Depto. de Física de Materiales, Facultad de Química, Universidad del País Vasco, Apdo. 1072, 20080 San Sebastian, Basque Country, Spain IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain waxslavas@sc.ehu.es

Recently it shown that polarization of a two-dimensional graphene sheet by an external charge produces an attractive image potential that supports, in addition to the well-known π* bands, a double series of Ridberg-like image potential states converging onto the vacuum level. Being quantified in the perpendicular to the graphene sheet direction, in the parallel plane these states have nearly free electron character like similar states on metal surfaces. A large extension of wave function of image-potential states into the vacuum implies that they are very sensitive to any change of shape and environment of the graphene sheet. Thus the properties of these states can be modified by an external electric field and a shape/geometry variation. The lowest-energy members of such states have been experimentally observed in graphene sheets grown on some substrates. Some examples of the such unoccupied electronic states in other cabon-based materials, like graphite, multilayer graphene, fullerenes, and nanotubes as having common origin with the graphene imagepotential states will be presented.

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Life science at the sharp end: recent developments in tip-based nanolithography in sensing, cell biology and diagnostics Robert J. Stokes NanoInk Inc, 8025 Lamon Ave, Skokie, IL 60077 USA, rstokes@nanoink.net

The depostion of biomaterials at the micro and nanoscale holds huge potential for medical and life sciences. Dip Pen Nanolithography速 (DPN速) is an established method of nanofabrication in which materials are deposited onto a surface via a sharp tip.[1] Recent advances in DPN technology have resulted in the ability to directly print biologically relevant materials, including DNA, antibodies and smaller proteins, onto a variety of surfaces under ambient conditions thus maintaining biological activity. We will present data that demonstrates the generation of features for ELISA-type systems and biosensors (electronic, optical and mechanical). Direct deposition of biomaterials onto existing chips or microstructures is significant in the development of biosensors and diagnostics.[2] In recent years several different micro mechanical machining systems (MEMS)-based sensing elements have found applications in biomolecular and chemical detection. An important advantage of MEMS sensors is that they can be easily multiplexed in a high density fashion to simultaneously detect multiple analytes from very small volumes. One of the factors limiting a wider application of these sensors is the fact that chemical or biological functionalization of these elements has been challenge. We will present data demonstrating the feasibility of placing multiple proteins on microscale structures. Examples presented will include placement of proteins on microcantilever and microelectrodes. Recent research has focused on precisely controlling the microenvironment of cells. Tip-based direct protein printing is a relatively new technique in this field. The flexibility of the methods presented here enable the construction of complex patterns for cell culture studies and the ability to address cells at an individual level. We will report novel and fundamental demonstrating the placement of multiple proteins with subcellular resolution. We will also present the effect of these patterns on cell polarization.[3] Coculture studies have been useful for mimicking the in vivo environment and studying effects on stem or progenitor cell function. However, there are many experimental variables that cannot be properly controlled and may lead to confounding results. Herein we demonstrate a technique that allows spatial control of multiple cell types at single cell levels on a substrate. This single cell co-culture concept is demonstrated by utilizing the binding dynamics with fibronectin and laminin of 3T3 fibroblasts and C2C12 myoblasts. We further demonstrate the delivery of biology-effecting agents, including toxins, to a fraction of cells on a surface and determine the effects.

References [1] [2] [3]

R. D. Piner, J. Zhu, F. Xu, S. Hong, C.A. Mirkin, Science 283 (1999) 661. R. J Stokes, J. A. Dougan, D. Graham Chem. Commun. (2008) 5734. D.K. Hoover, E. W. L. Chan, M. N. Yousaf. J. Am. Chem. Soc. 130 (2008) 3280.

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Figures

Figure 1: A: Arrays of Fibronectin and Laminin depositions enabling cell co-culture. B: Flexible patterning at sub-cellular scales. C: Example fluorescence response curves from IL-1β (example from library) in an ELISA type assay showing the increase in sensitivity that is obtained from smaller features fabricated by the DPN process.

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Dynamics of magnetic nanoparticle with cubic anisotropy in a viscous liquid N. A. Usov1-3, M. L. Fdez-Gubieda1, and J. M. Barandiarán1 1

Departamento de Electricidad y Electrónica, Universidad del País Vasco (UPV/EHU), Apartado 644, 48080 Bilbao, Spain Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences, (IZMIRAN), 142190, Troitsk, Moscow region, Russia 3 IKERBASQUE, The Basque Foundation for Science, 48011 Bilbao, Spain usov@izmiran.ru

2

Magnetic nanoparticles are important for applications in various areas of nanotechnology, especially for biomedicine [1]. Bacterial magnetosomes are magnetite (Fe3O4) nanoparticles with nearly spherical shape. They have a magnetite core of a perfect crystal structure surrounded by a thin lipidic membrane. Magnetosomes are promising for applications in hyperthermia due to their biocompatibility and the very high specific absorption rate (SAR) [2] from high frequency magnetic fields. For a suspension of magnetic nanoparticles in a liquid, both Brownian and Néel relaxation mechanisms may be equally important [3], depending on the particle size, magnetic parameters and liquid viscosity. In the present report, the process of energy absorption from the alternating external magnetic field by a dilute assembly of magnetosomes nanoparticles with cubic type of magnetic anisotropy is studied by means of numerical simulation. Let n1, n2, n3 be an orthogonal set of the unit vectors that describes the space orientation of one nanoparticle and determines the directions of the easy anisotropy axes of its magnetic anisotropy. The kinematics equations of motion for these vectors are given by  dni   = [ω, ni ]; dt

i = 1 - 3,

(1)

where ω is the angular velocity of the particle rotation as a whole, as determined [4] by the corresponding Euler-Langevin stochastic equation   dω   (2) I + ξω = N m + N th , dt

Here I is the moment of inertia of a spherical particle and ξ = 6ηV is the drag coefficient, η being the dynamic viscosity of the liquid and V being the particle volume. In Eq. (2) Nm is the regular torque due to the external magnetic field acting on the particle, whereas Nth is the white noise torque related with the viscous friction forces. It has the following statistical properties [4] (i,j = x,y,z)

N th,i (t ) = 0 ;

N th,i (t )N th , j (t1 ) = 2kB Tξδij δ (t − t1 ),

(3)

where kB is the Boltzmann constant and T is the absolute temperature. The dynamics of the unit magnetization vector of the nanoparticle α is governed [5,6] by the stochastic Landau-Lifshitz equation    ∂α      (4) = −γ1 [α , H ef + H th ]− κγ1 α, [α, H ef + H th ] ,

[

∂t

]

where γ1 = |γ0|/(1+κ ), κ is the damping constant and γ0 is the gyromagnetic ratio. In Eq. (4) Hef is the effective magnetic field and Hth is the thermal field. The latter is assumed to be a Gaussian random process with the following statistical properties for its components [5] 2

H th ,i (t ) = 0 ;

H th,i (t )H th, j (t1 ) =

2k BTκ . δij δ (t − t1 ) γ 0 M sV

(5)

The total energy of a magnetic nanoparticle, with a cubic magnetic anisotropy in the alternating magnetic  field H 0 sin (ω t ) reads:

153


(

)

 2  2  2  2  2  2  W = K cV (α n1 ) (α n2 ) + (α n1 ) (α n 3 ) + (αn2 ) (α n3 ) − M sV α H 0 sin (ω t ) ,

(6)

where Ms is the saturation magnetization, Kc is the cubic magnetic anisotropy constant and ω = 2πf is the angular frequency of the applied magnetic field. Using Eq. (6) the effective magnetic field can be calculated as (7)  ∂W , H ef = −

 VM s∂α

whereas the regular torque acting on the particle is given by:   ∂W    ∂W    ∂W   . N m =   , n1  +   , n2  +   , n3   ∂n1   ∂n2   ∂ n3 

(8)

In the present paper, calculations of the low frequency hysteresis loops are carried out according to Eqs, (2)-(5) for magnetosome like spherical nanoparticles with saturation magnetization Ms = 480 emu/cm3 and cubic magnetic anisotropy constant Kc = - 105 erg/cm3. The single domain diameter of a particle having such magnetic parameters is estimated to be Dc = 64 nm. Therefore, the particle diameters are only investigated within the range D = 20 – 60 nm. The dynamic viscosity of a liquid is assumed to be close to that of water, η = 0.01 – 0.1 g/(cm*s). The ranges of magnetic field amplitudes and frequencies considered are typical for magnetic nanoparticle hyperthermia, i.e. H0 = 30 – 100 Oe and f = 100 – 500 kHz, respectively. To ensure the accuracy of the simulations performed, we use simple Milshtein scheme [6,7] and keep the physical time step lower than 1/50 of the characteristic particle precession time. For every particle diameter a time-dependent particle magnetization M(t) = Msα(t) is calculated in a sufficiently large series of numerical experiments, Nexp = 500 - 1000, for the same frequency and magnetic field amplitude. Because various runs of the calculations are statistically independent, the magnetization of a dilute assembly of nanoparticles is obtained [7] as a correspondent average value, <M(t)>. As Fig. 1 shows, in contrast to a uniaxial nanoparticle assembly in a rigid matrix [7], nanoparticles with cubic magnetic anisotropy show hysteresis loops of appreciable squareness even for a low amplitude of the external magnetic field, H0 = 30 Oe. The loops shown in Fig. 1 correspond to a stationary regime that is achieved after several periods of the alternating magnetic field have been elapsed. The optimal particle diameter for the parameters of Fig 1 is approximately D = 45 nm, and the corresponding SAR value is 207 W/g. It increases greatly as a function of H0. The dependence of the SAR of a dilute assembly of magnetosomes on the magnetic field parameters H0 and f, liquid viscosity η and particle diameter D will be fully discussed in the report. References [1] Q.A. Pankhurst, N.K.T. Thanh, S.K. Jones, J. Dobson, J. Phys. D: Appl. Phys. 42 (2009) 224001. [2] R. Herdt, et. al., J. Magn. Magn. Mater. 293 (2005) 80. [3] R.E. Rosensweig, J. Magn. Magn. Mater. 252 (2002) 370. [4] W.T. Coffey, Yu.P. Kalmykov, J. Magn. Magn. Mater. 164 (1996) 133. [5] W.F. Brown, Jr., Phys. Rev. 130 (1963) 1677. [6] J.L. Garcia-Palacios, F.J. Lazaro, Phys. Rev. B 58 (1998) 14937. [7] N.A. Usov, J. Appl. Phys. 107 (2010) 123909. Figures 1.0 Reduced magnetization

154

H0 = 30 Oe f = 300 kHz

0.5

η = 0.01 g/(cm*s)

Figure 1: Hysteresis loops of a dilute assembly of magnetosome like nanoparticles as a function of their diameter: 1) D = 30 nm; 2) D = 40 nm; 3) D = 50 nm; 4) D = 60 nm.

4

0.0

1 3

-0.5

2 -1.0 -30

-20

-10

0

10

Magnetic field (Oe)

20

30


Soft-organic Thin-films, based on Nanostructured Polymeric Composites, as Ultra-sensitive Piezoresistive Sensors for Biomedical Applications Jaume Veciana,1,2 Elena Laukhina,2,1 Raphael Pfattner,1,2 Lourdes R. Ferreras,1,2 Marta Mas-Torrent,1,2 Vladimir Laukhin,3,1,2 Concepció Rovira,1,2 1 Institut de Ciencia de Materials de Barcelona (CSIC), 08193- Cerdanyola, Spain CIBER de Bioingeniería, Biomateriales y Nanomedicina 08193-Cerdanyola, Spain 3 Institució Catalana de Recerca i Estudis Avançats , Barcelona, Spain. vecianaj@icmab.es

2

The development of intelligent materials that can respond to the application of an external stimulus is of major interest for the fabrication of artificial sensing devices able to sense and transmit information about the physical, chemical and/or biological changes produced in our environment. If these materials can be deposited or integrated on flexible and transparent substrates and processed employing low-cost techniques their appeal is greatly increased. Here, we present soft organic bi-layered thin films [1], composed of a polymeric matrix with a top-layer formed by a nanocrystalline network of a conducting molecular charge-transfer salt. These bilayered thin films are prepared by simple chemical methods that do not require any special conditions and facilities. One of the most surprising properties of such nanostructured thin films is their capacity to translate micron-scale elastic elongations of the film into reversible deformations of the soft organic charge-transfer salt crystals at the nanoscale [2,3]. These multiple length scale movements are responsible of the ultra sensitive piezoresistive properties of the nanostructured thin films that are extremely sensitive to strain changes with durable, fast and completely reversible responses. Such conducting, transparent, and flexible thin films showing a sensitivity one order of magnitude larger than the most commonly used electromechanical sensors have integrated in textiles that exhibit the same ultrasensitive piezoresistive sensitivity [4]. In addition, a few proof-of-concept experiments with simple prototypes for bio-medical applications (see Figures), based on such soft nanocomposite polymeric materials, will be reported [5,6]. References [1] [2] [3] [4] [5] [6]

M. Mas-Torrent, E. Laukhina, V. Laukhin, C.M. Creely, D.V. Petrov, C. Rovira, J. Veciana., J. Mater. Chem . 16, (2006) 543-545. E. Laukhina, R. Pfattner, L.R. Ferreras, S. Galli, M. Mas-Torrent, N. Masciocchi, V. Laukhin, C. Rovira, and J. Veciana, Adv. Mater. 22, (2010) 977-981. E. Laukhina, M. Mas-Torrent, C. Rovira, J. Veciana, V. Laukhin, Patent Appl., WO2008059095. L.R. Ferreras, R. Pfattner, M. Mas-Torrent, E. Laukhina, L. López, V. Laukhin, C. Rovira, J. Veciana. J. Mater. Chem., 21, (2011) 637-640. V. Laukhin, I. Sánchez, A. Moya, E. Laukhina, R. Martin, F. Ussa, C. Rovira, A. Guimera, R. Villa, J. Aguiló, J.-C. Pastor, J. Veciana, Sensors & Actuators: A, 170 (2011) 36-43 I. Sanchez, V. Lauhkin, A. Moya, R. Martin, F. Ussa, E. Lauhkina, A. Guimera, R. Villa, C. Rovira, J. Aguilo, J. Veciana, J.C. Pastor, Invest. Ophthalmol. Vis. Sci., 52 (2011) 83100.

Figures

Figure 1: Examples of biomedical prototypes made with the piezoresistive thin film

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Multifunctional Composites Based on Nanocarbons J.J. Vilatela, B. Mas, J.P. FernĂĄndez-BlĂĄzquez, M. MonclĂşs, J. Molina IMDEA Materials, Profesor Aranguen s/n 28040, Madrid, Spain juanjose.vilatela@imdea.org

This talk starts with a review of the different strategies to incorporate nanocarbons (CNTs, graphene) in polymer matrices and their relative merit in terms of mechanical reinforcement, improvement in electrical/thermal conductivity and emergence of other functional properties, such as sensing capabilities [1] [2]. Three types of nanocomposites are discussed: the first type corresponds to composites where the nanocarbon is used as a filler added to a polymer matrix, the second consists of hierarchical composites with macroscopic fibres and nanocarbon in a polymer, typically thermosetting matrix; the third type are nanocarbon-based macroscopic fibres which can be processed to form standard fibre reinforced polymer (FRP) composites (Figure 1). We then show examples of experimental results of low volume fractions nanocomposites with a high level of reinforcement and a significant increase in thermal conductivity. The effects of the nanofiller on the matrix are particularly noticeable in the low volume fraction regime; in this work we use by Raman spectroscopy to study the stress-transfer between nanocarbons and the matrix, and the possible residual strains in the composites due to mismatch in coefficients of thermal expansion. The stiffening of the polymer through reduced mobility and its increase in thermal stability are analysed by standard DMA and related to results obtained using a state-of-the-art nanoindentation DMA system. References [1] [2] [3]

[4] [5]

J J Vilatela and D Eder, "Nanocarbon composites and hybrids in sustainability: a review," Chem. Sus. Chem., vol. In press, 2012. R Guzman de Villoria, N Yamamoto, A Miravete, and B Wardle, "Multi-physics damage sensing in nano-engineered structural composites ," vol. 22, p. 185502, 2011. E Logakis et al., "Low electrical percolation threshold in poly(ethylene terephthalate)/multiwalled carbon nanotube nanocomposites," European Polymer Journal, vol. 46, pp. 928 - 936, 2010. E J Garcia, B L Wardle, and A J Hart, "Joining prepreg composite interfaces with aligned carbon nanotubes," Composites: Part A, vol. 39, pp. 1065 - 1070, 2008. R J Mora, J J Vilatela, and A H Windle, "Properties of composites of carbon nanotube fibres," Comp. Sci. Tech. , vol. 69, pp. 1558 - 1563, 2009.

Figures

Figure 1: Electron micrographs of different nanocarbon composite types (top) and their schematic representation (bottom). Micrographs from references [3] [4] [5].

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Synthesis and Characterization of Graphene Alba Centeno1, Andrey Chuvilin2, Amaia Pesquera1, Beatriz Alonso1 and Amaia Zurutuza1 1

Graphenea, Tolosa Hiribidea 76, E-20018 Donostia-San Sebastian, Spain CIC nanoGUNE Consolider, Tolosa Hiribidea 76, E-20018 Donostia-San Sebastian, Spain a.zurutuza@graphenea.com

2

Researchers envision many different applications for graphene. Depending on the application the required graphene format can vary from powder/flake to homogeneous film form. The powder form can be obtained starting from graphite while the large area graphene films can be obtained using silicon carbide sublimation and chemical vapor deposition (CVD) methods. In the CVD method, graphene is synthesized via the deposition of a carbon source on a metallic catalyst substrate at high temperatures. Copper and nickel metals have been widely used as graphene catalysts during CVD growth. Copper has been reported to control better the monolayer graphene growth [1]. However, the growth is not the only process that needs to be optimized in order to have high quality graphene on insulating substrates. The graphene transfer process is as important as the growth since the synthesized graphene can easily be damaged during the transfer. After a careful characterization of our monolayer graphene by means of Raman and optical microscopy, the limiting factors for a successful graphene transfer were determined. Moreover, we have also obtained suspended graphene samples which were characterized via High Resolution TEM and Scanning mode TEM [2].

References [1] [2]

X. Li, W. Cai, J. An, S. Kim, J. Nah, D. Yang, R. Piner, A. Velamakanni, I. Jung, E. Tutuc, S. K. Banerjee, L. Colombo, R. S. Ruoff Science, 324 (2009) 1312. H. J. Park, J. Meyer, S. Roth, V. Skรกkalovรก Carbon, 48 (2010) 1088.

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Orals - Parallel Sessions

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Tunable Diffraction Devices Based On Spin Crossover Materials Akou Amal,a , Gural’skiy Il’ya,a Thibault Christophe,b Bartual Carlos,b Salmon Lionel,a Molnár Gábor,a Bousseksou Azzedinea a

Laboratoire de Chimie de Coordination, CNRS UPR 8241 and Université de Toulouse (UPS, INP), 205 route de Narbonne, 31077 Toulouse Cedex 04 France b CNRS ; LAAS ; 7, avenue du Colonel Roche, F-31077 Toulouse, France Amal.akou@lcc-toulouse.fr

The spin crossover phenomenon in transition metal complexes is one of the most spectacular examples of molecular bistability. The switching between the two different electronic states of these molecules can be achieved using various external perturbations like a change of temperature or by applying an external pressure, light irradiation, pulsed magnetic field, and even a change of the concentration of chemical species around the samples. Hence the potential applications of these materials for the construction of sensor and memory devices continue to draw much attention.[1] In our team we have succeeded to elaborate thin films[2] and nanopatterns[3] of these materials displaying room temperature spin crossover. Different methods were developed to detect the spin crossover phenomenon in the films, but these techniques become limited when the film thickness decreases below ca. 100 nm (depending on the compound). To overcome this limitation we propose an alternative method where sensing is based on the variation of the diffracted intensity by a periodic pattern of the thin film material due to the change of the optical properties associated with the spin state change.[4] In this presentation, we will discuss the fabrication of surface-relief gratings of the complex [Fe(hptrz)3(OTs)2] by using “soft lithography“ methods (micro-molding in capillaries[5]) as well as their physical properties. These spin crossover gratings can respond reversibly to various external stimuli with fast response times. The response can be either transient (gating) or non-volatile (switching) – depending on the compound and on the experimental conditions. We believe that these assets provide a clear technological interest in a variety of applications including optics, photonics and chemical sensors. References [1] [2] [3] [4] [5]

A. Bousseksou, G. Molnár, L. Salmon, W. Nicolazzi, Chem. Soc. Rev., 40 (2011) 43313–3335. S. Cobo, G. Molnár, J.A. Real, A. Bousseksou, Angew. Chem. Int. Ed., 45 (2006) 5786-5789. G. Molnár, S. Cobo, J. A. Real, F. Carcenac, E. Daran, C. Vieu, A. Bousseksou, Adv. Mater., 19 (2007) 2163-2167. A. Akou, I. Gural’skiy, L. Salmon, C. Thibault C. Bartual. C. Vieu, G. Molnár, A. Bousseksou, J. Mater. Chem. in press (2012) DOI:10.1039/C2JM15663F. Y. Xia, E. Kim, G.M. Whitesides, Chem. Mater., 8 (1996) 1558-1567.

Figures

Figure 1: (a) Diffraction pattern of a 100 lines/mm surface-relief grating of the spin crossover complex [Fe(hptrz)3(OTs)2], (b) schematic picture of the grating geometry, (c) its AFM image and (d) the temperature dependence of the diffraction efficiency through two thermal cycles.

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Magneto-optical effects in nano-disks as a perturbation of the optical response R. Alcaraz de la Osa1, J. M. Saiz1, F. Moreno1, P. Vavassori2,3 and A. Berger2 1

Grupo de Óptica, Dept. Física Aplicada. Universidad de Cantabria, Avda. de los Castros s/n, Santander, Spain 2 CIC nanoGUNE Consolider, Tolosa Hiribidea 76, E-20018 Donostia-San Sebastián, Spain 3 IKERBASQUE, Basque Foundation for Science, E-48011 Bilbao, Spain alcarazr@unican.es

Electromagnetic scattering from nanometer-scale particles is currently a topic of considerable interest, which is being investigated both theoretically and experimentally for the purpose of understanding the underlying physics and to study novel near- and far-field optical and magneto-optical effects [1–5]. To address fundamental issues of magneto-optical scattering from nanometer-scale magnetic structures, we have investigated the optical and magneto-optical responses of nano-scale ferromagnetic (cobalt) disks arrays by means of self-consistent numerical simulations, using an extension of the discrete dipole approximation [6]. We also implemented an approach to the problem by modeling the nanoscale-disk with an array of radiating dipoles interacting as if they were belonging to an infinite film. This infinite layer (IL) approach neglects the effects of the lateral confinement on the induced dipoles distribution and it is used as a reference for the full calculations. Specifically, we studied the case of 5 nm thick cobalt disks in the diameter range from 200 to 1000 nm, illuminated under normal incidence with a wavelength of λ = 632.8 nm. We furthermore assumed the magnetization to lie in the plane of the disk and being oriented perpendicular to the electric field of the incoming electromagnetic wave, i.e. the transverse magnetooptical Kerr effect (T-MOKE) configuration. The induced polarization pattern and the near- and far-field optical and magneto-optical responses have been calculated, finding clear nano-scale confinement effects as one reduces the diameter of the disks (see Fig. 1). However, we also observe that the rather weak magneto-optical response essentially mimics the optical response, and we demonstrate that it can be calculated as a perturbation of the latter with a high degree of accuracy. This strong similarity between the optical and magneto-optical nano-scale confinement effects also results in the fact that the normalized magneto-optically induced far-field light intensity change, which is the quantity measured in experiments, is only weakly affected even in the case of sub-wavelength sized disks (see comparison with results from our IL approach in Fig. 2). Acknowledgements This research has been supported by MICINN under projects #FIS2010-21984 and MAT2009-07980. Work at nanoGUNE acknowledges funding from the Basque Government under Program #PI2009-17. R. Alcaraz de la Osa thanks the Ministry of Education of Spain for his FPU grant. The authors thank F. González for his valuable comments and helpful discussions.

References [1] [2] [3] [4] [5] [6]

M. Grimsditch and P. Vavassori, J. Phys.: Condens. Matter 16, R275 (2004). J. B. González-Díaz, J. M. García-Martín, A. García-Martín, D. Navas, A. Asenjo, M. Vázquez, M. Hernández-Vélez and G. Armelles, Applied Physics Letters 94, 263101 (2009). M. I. Stockman, Physics Today 64, 39 (2011). V. Bonanni, S. Bonetti, T. Pakizeh, Z. Pirzadeh, J. Chen, J. Nogués, P. Vavassori, R. Hillenbrand, J. Åkerman and A. Dmitriev, Nano Letters (2011), 10.1021/nl2028443. R. Alcaraz de la Osa, J. M. Saiz, F. Moreno, P. Vavassori and A. Berger, submitted to Phys. Rev. B. R. Alcaraz de la Osa, P. Albella, J. M. Saiz, F. González and F. Moreno, Opt. Express 18, 23865 (2010).

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Figures

D = 200 nm

D = 400 nm D = 600 nm D = 800 nm D = 1000 nm 1.5

1

0.5 Figure 1: Absolute value of the primary optical (upper panel) and the magneto-optical (lower panel) components of the induced dipole moment for several disk diameters D normalized to an equivalent infinite layer (IL) calculation.

166

Figure 2: Normalized magneto-optical intensity change signal ΔI/I vs. diffraction angle φ for several horizontal diffraction orders m: D=200nm with λ=632.8nm.


In vitro toxicity studies of polymer coated superparamagnetic iron oxide nanoparticles Lamiaa M.A.Ali1, 2, Víctor Sorribas2*, Rafael Piñol1, Lierni Gabilondo1, Angel Millán1,Fernando Palacio1* 1

Instituto de Ciencia de Materiales de Aragón. CSIC - Universidad de Zaragoza, Spain. palacio@unizar.es 2 Laboratory of Molecular Toxicology, Universidad de Zaragoza, Spain. sorribas@unizar.es

Superparamagnetic iron oxide nanoparticles (SPIONs are inorganic nanomaterials involved in many biological and medical applications, e.g., in diagnosis as MRI contrast agent or in therapy as an agent in hyperthermia treatments. Our model consists of ferric oxide nanoparticles embedded within poly(vinylpyridine) (P4VP) and coated with polyethylene glycol (PEG). A fraction of coating PEG can also be functionalized for the conjugation of fluorescent dyes, antibodies and drugs. The particles are dispersed in phosphate buffer saline (PBS) at pH 7.4 to mimic physiological conditions. The resulting ferrofluids have core diameter (ferric oxide nanoparticles diameter) ranging between 4 to 15 nm, with 10% size dispersion, and hydrodynamic diameter ranging between 50 to 164 nm. Cytotoxicity studies of the ferrofluids have been carried out in two different cell lines [1], opossum kidney cells (OK) and vascular smooth muscle cells (VSMS). The activity of the lactate dehydrogenase in culture media was determined as a function of the dose. LC50 has been calculated and the toxic effect was due to accumulative effects with time. Ethidium bromide/acridine orange tests with the help of the fluorescent microscope show that the cell death is due to necrosis rather to apoptosis. These results are confirmed by DNA fragmentation test. No oxidative stress findings have been observed. The studies have been extended to determine the cytotoxicity effects of the magnetic core particles as a function of their size. The results show that cytotoxicity increases as the diameter of the nanoparticles decreases. Sub cellular tracking studies have been carried out using fluorescent nanoparticles. The results show the localization of the nanoparticles after 24h of incubation with the cells inside the endolysosomal system, as shown in the Figure. Kinetic studies show the internalization of the nanoparticles inside the cells after 4h of incubation, increasing with time until 12 h and then decreasing. Nanoparticles uptake takes place by clathrin-dependent endocytosis and the rate of internalization depends on cell line and nanoparticles size. References [1]

Figures

R. Villa-Bellosta, G. Ibarz, A. Millan, R. Piñol, A. Ferrer-Dufol, F. Palacio, V. Sorribas. Toxicol. Lett., 180, S221, (2008).

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Assessing toxicity of citrate-gold nanoparticles at different marine trophic levels (microalgae, copepods and bivalve mollusks) Julián Blasco1, Ignacio Moreno-Garrido1, Miriam Hampel1, Jorge Otero1, Gonzalo Quiroga1, Moritz Volland1, Carlos. A García-Negrete2, A. Lapresta-Fernández2, Asunción Fernández2 1

2

Instituto de Ciencias Marinas de Andalucía (CSIC). Campus Río San Pedro.11510 Puerto Real (Cadiz). Spain Instituto de Ciencia de Materiales de Sevilla, CSIC-Univ.Sevilla, Avda. Américo Vespucio 49, 41092-(Seville). Spain julian.blasco@csic.es

Engineered nanoparticles (ENPs) may offer benefits to society in general, although they sometimes inherently have unintended effects on ecosystems. As a consequence, assessment of the environmental safety of ENPs has become a major issue worldwide [1]. Within the metallic ENPs, gold nanoparticles have been used extensively in drug delivery, gene therapy, biosensing and contrast agent for imaging [2]. However, studies about the effects of gold nanoparticles are limited and they are specially focused on “in vitro” experiments rather than “in vivo” systems. Additionally, estuaries and coastal ecosystems are the final receptors of substances dumped in the environment wherefore the effects of these substances should be tested in representative site specific organisms. In order to assess the effect of gold-citrate nanoparticles on aquatic ecosystems, toxicity tests were carried out in three groups of model organisms belonging to different trophic levels: the marine microalgae species Cylindrotheca closterium, Chlorella autotrophyca, Phaeodactylum tricornutum, Pleurochrysis pseudoroscoffensis and Rhodomonas salina (Fig. 1), the copepod, Tisbe battagliai (Fig. 2) and the clam Ruditapes philippinarum (Fig. 3). The gold-citrate NPs employed were citrate reduced AuNPs in the range of 20 – 30 nm, or soluble gold, H(AuCl4) as positive control. For the toxicity test with microalgae, the selected endpoint was population growth after 72 hours of exposure. The cells were incubated in batch cultures of 50 mL in artificial seawater enriched with simple medium (nitrate, phosphate, silica) and exposed under continuous light conditions at 20±1ºC to different dissolved Au or NPs concentrations. Growths of experimental populations were compared with controls, and concentrations which imply an inhibition of 50% respect the controls (EC50%) are calculated (Fig. 4). Dissolved Au toxicity ranged from 0.052 ± 0.001 mg•L-1 for Rhodomonas salina to 0.50 ± 0.15 mg•L-1 for Chlorella autotrophyca. Concentrations at ecologically significant values for NPs (up to 0.3 mg•L-1) did not imply growth inhibitions over 50%. For copepods, nauplii (< 24 h-old) were exposed (48 h) to increasing concentrations of Au-NPs in 12-well plates (5 ml/well, 4 nauplii/well and 5 replicates/concentration) under the above described laboratory conditions [3]. The results are shown in Figure 5. The clam, Ruditapes philippinarum was exposed for 28 days to two Au-NPs concentrations: 6 and 30 μg·L-1. Clams were collected different at sampling points and target tissues (gills, digestive gland and mantel) were dissected and stored at -80ºC until their analysis. No significant mortality was recorded during the experiment and bioaccumulation in the digestive gland along the experiment was measured (Figure 6). In summary, no acute toxicity was recorded at ecological relevant concentrations for assayed Au-NPs. Nevertheless, further research should be necessary to know the effect of chronic exposure to these NPs and to improve the knowledge about their environmental risk assessment. References [1] [2] [3]

A. Lapresta-Fernández, A. Fernández, J. Blasco. Environmental International, 39 (2012) 148-149. O. Bar-Ilan, R. M. Albrecht, V. E. Fako, D. Y. Furgeson. Small, 5 (2009) 1897-1910 Diz F.R., Araujo C.V.M., Moreno-Garrido I., Hampel M., Blasco J. Ecotoxicol. Environ. Safety 72 (2009) 1881-1886

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Figures

Figure 1: Phytoplankton species (A. Chlorella autotrophyca (CHLOROPHYCEAE) B. Cylindrotheca closterium (BACILLARIOPHYCEAE), C. Phaeodactylum tricornutum (BACILLARIOPHYCEAE); D. Pleurochrysis pseudoroscoffensis (PRIMNESIOPHYCEAE); E. Rhodomonas salina (CRYPTOPHYCEAE))

Figure 2: Second stage copepodid and naupliae stage of Tisbe battagliaĂ­ (crustacean: Copepoda)

170

Figure 3: Specimens philippinarum

of

the

clam

Ruditapes Figure 4: Effect of AU-NPs and Au(III) on P. tricornutum

Figure 5: Tisbe battagliai mortality (%) vs Au-NPs concentration

Figure 6: Gold concentration in digestive gland of R. philippinarum collected at several exposure times


Design of a competitive electrochemical biosensor based on affinity reaction between deoxynivalenol and its polyclonal antibody L. Bonel2 , S. Hernández2, JC. Vidal1 and JR. Castillo1 1 Institute of Environmental Sciences (IUCA) Analytical Spectroscopy and Sensors Group (GEAS) University of Zaragoza. Ciudad Universitaria, 50009, ZARAGOZA. Spain 2 CAPHER IDI S.L, C/Ermesinda de Aragón, 4, nº116, 50012, ZARAGOZA, Spain lbonel@capher.es

Deoxynivalenol (DON) is a mycotoxin produced by Fusarium fungi, which are abundant in certain cereals such as wheat, corn, barley, oats, and rye and their processed grains such as malt, beer or bread. DON inhibits the synthesis of DNA and RNA and protein ribosomes. DON causes vomiting, and if the concentration taken in the diet is lower growth and reduced food consumption (anorexia). Due to the great importance of mycotoxins in food contamination, the Spanish and European legislation are demanding in recent years a extrict control. Maximum permissible concentrations of DON for different foods, are between 200 and 1750 µg/Kg, and the tolerable daily intake is 1 µg/Kg body weight (Commission Regulation No. 1126/2007). This work proposes a direct competitive electrochemical immunosensor where we immobilize the biorecognition element and then the competitive reaction takes place between DON and DON-HRP. Electrochemical transduction is done by the chronoamperometry technique (CRA). Previously to the development of this immunosensor, we have optimized the different parameters and variables with the technique ELISA. A highly specific polyclonal antibody to DON is immobilized onto magnetic nanoparticles modified with different functional groups. Nanoparticles magnetic beads (MBs) functionalized have been modified with a polyclonal antibody specific to DON (pAbDON). After separation and washing steps, the modified magnetic beads were localized on disposable screen-printed carbon electrodes (SPCEs), and the product of the enzymatic reaction with the substrate was detected by chronoamperometry. This biosensor will be a direct immunosensor (immobilized biorecognition element) and competitive and electrochemical detection is performed by an electrochemistry technique.

Acknowledgments: Science and Innovation Ministry for two new contracts INC10-0178 (INNCORPORA 2010) PTQ-10-03580 (TORRES QUEVEDO 2010), one project IPT-2011-1766-010000 (INNPACTO 2011) and a predoctoral grant AP2010-4609.

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Superparamagnetic Core-Shell Nanoparticles: Synthesis, Characterization and Application in Targeted Drug Delivery Eugenio Bringas‡, Elena Aznar#,Δ, Inmaculada Ortiz‡, Ramón Martínez-Mañez#,◊,Δ, Pieter Stroeve† ‡

Department of Chemical Engineering and Inorganic Chemistry, ETSIIT, University of Cantabria, Avda. de los Castros s/n, 39005 Santander, Cantabria, Spain. # Centro de Reconocimiento Molecular y Desarrollo Tecnológico (IDM). Unidad Mixta Universitat Politècnica de ValènciaUniversitat de València, Spain. ◊ Departamento de Química. Universitat Politècnica de València. Camino de Vera s/n, 46022, Valencia, Spain. Δ CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Valencia, Spain. † Department of Chemical Engineering and Materials Science, University of California, Davis, California 95616, United States. bringase@unican.es

In recent years, since research into the targeting and delivery of therapeutics is right at the forefront of nanomedicine, scientists have developed different kinds of drug delivery systems. In this field, the design of chemical and physical stimuli-responsive gated mesoporous materials have recently demonstrated to be an excellent approach for the development of smart nanodevices. In fact, the unique characteristics of functionalized mesoporous silica supports such as high homogeneous porosity, inertness, robustness, thermal stability, the presence of tunable pore sizes, homogeneous pore distribution and high loading capacity, makes these scaffoldings ideal for hosting functional guest molecules. Additionally, the possibility of incorporating in the external surface functional groups able to open or close at will or including capping molecules, provides advanced control release applications. One of the most captivating features of such systems is the possibility to prepare “zero release” devices that deliver entrapped guests exclusively upon the application of an external stimulus [1,2]. Among different physical triggers, such as light and temperature, the use of magnetic fields is captivating [3,4]. This work reports the on-command cargo controlled delivery using an alternating magnetic field (AMF) from magnetic silica mesoporous supports capped with a lipid bilayer [5]. Silica mesoporous nanoparticles containing superparamagnetic iron oxide nanocrystals (solid S1) were synthesized and loaded with the dye methylene blue [6]. Further, the pores were capped with a lipid bilayer of 1,2-dioleoyl-sn-glycero-3phosphocholine (solid S2). The synthesis procedure is summarized in Figure 1.

Figure 1: Synthesis of superparamagnetic core-shell nanoparticles.

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Delivery of the dye from S2 in the presence of an isolated AMF (50 Hz and 1570 G) was studied in a phosphate-buffered saline medium (PBS; pH 7.4) at 20 ºC and compared with the release behavior in absence of the magnetic field (see Figure 2).

Figure 2: i) Solid S2 expected performance; ii) Cumulative release profile of methylene blue from solid S2 a) without AMF and b) in the presence of an AMF.

Whereas solid S2 displayed no release of the cargo, the application of an AMF induced the delivery of more than 90% of the maximum deliverable methylene blue dye during the first four hours. Delivery mechanism occurs most likely due to changes in the permeability of the lipid bilayer (and eventually its total or partial rupture) promoted by the vibration of the nanoparticles in the presence of an AMF.

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The easy preparation of the nanomaterial, the robustness and high loading capacity of the cargo reservoir, the wide range of possibilities as well as the biocompatibility of lipid bilayers, combined with the remote release activation using a friendly simple alternating magnetic field make these new hybrid nanomaterials attractive systems for the future design of on command delivery nanodevices in a wide range of applications. Acknowledgement: Financial support from the Spanish Government (projects CTQ2008-00690 and MAT2009-14564-C04-01) is gratefully acknowledged. References [1] [2] [3] [4] [5] [6]

Aznar, E.; Martínez-Máñez, R.; Sancenón, F. Expert Opin. Drug Deliv.6 (2009) 643-655. Cotí, K.; Belowich, M. E.; Liong, M.; Ambrogio, M.W.; Lau, Y.A.; Khatib, H.A.; Zink, J.I.; Khashab, N.M.; Stoddart, J.F. Nanoscale, 1 (2009) 16-39. Ruiz-Hernández, E.; Baeza, A.; Vallet-Regí, M. ACSNano, 5 (2011) 1259-1266. Bringas, E.; Köysüren, O.; Quach, D.V.; Mahmoudi, M.; Aznar, E.; Roehling, J.D.; Marcos, M.D.; Martínez-Máñez, R.; Stroeve, P. submitted, Angew. Chemie Int. Ed. (December 2011). Zhang, L.; Longo, M.L.; Stroeve, P. Langmuir, 16 (2000) 5093-5099. Bruce, I.J.; Taylor, J.; Todd, M.; Davies M.J.; Borioni, E.; Sangregorio, C.; Sen, T. J. Magnet. Magnet. Mater. 284 (2010) 145-160.


The frontier of the Environmental Analytical Nanotechnology Single Nanoparticle Detection by ICP-Mass Spectrometry Cell Toxicity and Genotoxic Assays J.R.Castillo1, F. Laborda1, J. Jiménez-Lamana1, E. Bolea1, G.Cepria 1 L. Arola2, M.J. Salvadó2, C. Bladé2 1

Institute of Environmental Sciences (IUCA), Group of Analytical Spectroscopy and Sensors (GEAS), University of Zaragoza, Pedro Cerbuna, 12, 50009, Zaragoza, Spain. 2 Group of Nutrigenomics, University Rovira i Virgili, Campus Sescelades, C. Marcel.li Domingo s/n43007, Tarragona, Spain. jcastilo@unizar.es

The use of engineered nanoparticles (ENPs) is rapidly increasing and it is inevitable that they are released in the environment, where their fate and behaviour are largely unknown. Nowadays, the lack of reliable methods to determine ENPs identity, concentrations and characteristics in complex environmental samples at environmentally relevant concentrations, is one of the largest gaps in environmental nanosciences. Single particle detection using ICP-MS can be considered as one of the challenging analytical approaches necessary to assess the environmental impact of the release of ENPs into the environment. In single particle detection, when one nanoparticle is introduced into the ICP, the atoms of the analyte produce a flash of gaseous ions in the plasma, which are measured as a single pulse by the detector. The number of counts of this single pulse is related to the quantity of analyte atoms in the nanoparticle, and the frequency of the pulses is proportional to the number concentration of nanoparticles. Adequate time resolutions are required to ensure that each pulse correspond to just one nanoparticle. On the other hand, the analyte in dissolved forms will produce pulses of averaged constant intensity. The different behaviours of dissolved silver and silver nanoparticles under ICP-MS single particle detection conditions have been used to differentiate directly between both forms of silver. A methodological approach based on single particle detection using ICP-MS for identification, characterization and determination of mass and number concentration of silver nanoparticles in aqueous samples will be presented. The recommended minimum physical and chemical parameters for characterizing nanomaterials in toxicological studies should include [2]: Particle size/size distribution, agglomeration state/aggregation, shape, overall composition, surface composition, purity, surface area, surface chemistry and surface charge. In addition, some overarching considerations should be taken into account: (i) Stability—how do material properties change with time storage, handling, preparation, delivery...? including the material release through dissolution. (ii) Context/media—how do nanomaterial properties change in different media? [3] In vitro cell-based assay systems are important tools in the field of nanotoxicology. The considerations mentioned above with respect to knowing how the nanomaterial behaves in the test system are especially important for in vitro systems because nanoparticles can exhibit strong interactions with culture media. The formulation of the culture medium with respect to serum concentration, pH, and other factors can influence the behavior of nanoparticles and their response in the cellular system. We are going to describe the effects of a commercial nano silver product described in pharmacopeia as strong antiseptic, has been extensively characterized and its toxicity in hepatic human cells has been

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studied. Furthermore, silver nanoparticles and other forms of soluble silver have been identified and characterized in different culture media. The nanomaterial is a granulated powder with a total silver content of around 70%. It contains metallic silver nanoparticles below 20 nm, but small amounts of Ag(I) are also present. Toxicity test were performed with the human hepatocellular carcinoma cell line HepG2. Cell viability and genotoxicity were evaluated by the Neutral Red Uptake Cytotoxicity Test and the Alkaline Single-Cell Gel Electrophoresis (Comet Assay), respectively. Cell viability test showed that the product has no effect up to 15 mg/L. At higher concentrations, the antiseptic drug reduces the cell viability significantly, showing a dose-response effect. IC50 for product on HepG2 is 35-37 mg/L. The drug is moderately genotoxic at 10 and 20 mg/L, whereas it is highly genotoxic from 40 mg/L. The stability and behavior of silver components in this material was studied in the culture media DMEM (Dulbecco Modified Eagleâ&#x20AC;&#x2122;s medium) and RPMI (Roswell Park Memorial Institute medium) supplemented with fetal bovine serum, used along the toxicity tets. Asymmetric Flow Field Flow Fractionation (AsFlFFF) coupled to UV-Visible and ICP-MS detection was used for characterization of silver nanoparticles and Ag(I) species in these media. Nanoparticle aggregation as well as dissolution and complexation of Ag(I) with serum proteins were observed. Analytical methodology as well as detailed results will be presented.

This work has been sponsored by the Project CTQ 2009-14237-CO2-01 of the Spanish Ministry of Science and Innovation, and the Project CTP P06/10 (Comunidad de Trabajo de los Pirineos)

References

176

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Boverhof, D.R., David, R.M., Analytical and Bioanalytical Chemistry, 396 (2010) 953-961. Card, J.W., Magnuson, B.A., Journal of Food Science, 74 (2009) viâ&#x20AC;&#x201C;vii. http://www.characterizationmatters.org.


Compression enhanced conductivity in carbon nanotubes Elena del Corro,1,2 Elizabeth Castillo-Martínez, 2,3 Mercedes Taravillo, 1 Ray H. Baughman,2 Valentín García Baonza1 1

2

MALTA-Consolider Team, Depto. de Química Física I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain NanoTech Institute of the University of Texas at Dallas, P.O. Box 830688, M/S: BE26 Richardson, Texas 75083-0688, USA 3 CIC energigune, Parque Tecnológico de Álava, Albert Einstein 48-ED, CIC 01510 Miñano, Spain edelcorro@quim.ucm.es

The applicability of carbon nanotubes as field effect transistors [1], has stimulated large investigations of the electronic transport in this kind of devices. The understanding of the transport properties goes trough the study of the tunneling phenomena which play a key role. In this work, we have studied the electronic properties of multi-walled carbon nanotubes (MWCNTs) samples which were produced as continuous, free standing, lightweight, translucent and conducting sheets where nanotubes are preferentially oriented along their longitudinal direction [2]. Continuous stress cycles (between 3 and 10) up to 5 GPa were performed using a sapphire anvil cell [3], shown in the figure, and, at the same time, the resistance and the Raman spectrum of the sample were registered. The combination of both measurements with stress allowed us to identify the different mechanisms invoked to explain the conductivity in CNTs samples [4, 5]. During the first stress cycles some irreversible phenomena could be observed; on one hand with applying stress the original sample is debundled which affects the inter-tube conductivity, on the other hand the stress cycles cause the generation of hopping defects in the graphene lattice leading to a progressive increase of the resistance along the tubes, only after performing enough stress cycles the defect concentration reach a constant value and the resistance stop increasing. However, the changes of resistance due to the aforementioned phenomena are negligible in comparison with the abrupt and reversible variations observed at around 2 GPa. The large changes of resistance are consequence of variations of the inter-tube distance when the nanotubes are squeezed with the anvil cell, which demonstrate the effect of the tunneling phenomena on the conductivity of carbon nanotubes samples already described in the literature. Interestingly, we have found that the Raman intensity of the D band, as well as other double resonance Raman modes of carbon nanotubes, suffers a similar reversible variation to that observed for the resistance; consequently we can assume that, apart from the defect concentration, other factor such as the inter-tube distance is modulating the intensity of this band. This novelty result clearly indicates that the tunneling phenomena have a strong influence on the electronic band structure of carbon nanotubes.

References [1] [2] [3] [4] [5]

Knoch, J., Appenzeller, J. Phys. Stat. Sol. A, 205 (2008) 679. Zhang, M., Fang, S., Zakhidov, A. A., Lee, S. B., Aliev, A. E., Williams, C. D., Atkinson, K. R., Baughman, R. H. Science, 309 (2005) 1215. del Corro, E., Taravillo, M., González, J., Baonza, V. G. Carbon, 49 (2011) 973. Stahl, H.; Appenzeller, J., Martel, R., Avouris, Ph., Lengeler, B. Phys. Rev. Lett., 85 (2000) 5186. Bulat, F. A., Couchman, L., Yang, W. Nano Lett., 9 (2009) 1759.

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Figures

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Figure 1: (a) Photograph of the open SAC coupled with the pin. (b) Photograph of the freestanding MWCNTs sheet supported between the poles of the pin. (c) Photograph of the MWCNTs sheet on top of the sapphire culet after removing some of the sample. (d) Schematic representation of lateral view of the experimental set up used in these experiments; the numbered parts of the device are: (1) cell, (2) sapphire, (3) pin, (4) MWCNT sheet and (5) height adapter.


Electronic structure influence on the conductivity through open- and closed-shell molecules N. Crivillers,1,2 C. Munuera,1 M. Paradinas,1 M. Mas-Torrent,1,2 C. Simão,1,2 S. T. Bromley,3,4 C. Ocal,1 C. Rovira,1,2 J. Veciana1,2 1 Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra,Spain. 2 Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN) ICMAB-CSIC,Bellaterra,Spain. 3 Departament de Quıímica Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona,08028 Barcelona, Spain. 4 Institució Catalana de Recerca i Estudis Avançats (ICREA),08010 Barcelona, Spain ncrivillers@icmab.es

Molecular Spin Electronics or Molecular Spintronics[1] is a novel field in which the effort is being placed on exploring the spin transport properties of organic systems (i.e. spin injection and spin conservation). Its high potential in applications such as novel spin-based magnetic recording and memory devices has recently aroused high attention. Our study relies on the transport properties comparison between two self-assembled monolayers (SAMs) based on polychlorinated triphenylmethyl (PTM) derivatives, in the radical (magnetic) and non radical (diamagnetic) form. These SAMs exhibit small differences in their molecular structure but strongly differ in their electronic configuration (closed and open-shell forms). The investigation of the transport properties was performed by the so-called 3D operation mode of C-SFM. Similar measurements were carried out on SAMs prepared following two different approaches. In the first one, PTM molecules were grafted to a gold surface which was previously modified[2] and second, a novel PTM molecule was designed to be anchored to the Au in one step leading to a fully conjugated system bonded to the surface thus, resulting in a larger hybridization of the molecules with the metal (Figure 1).[3] In both cases the open-shell form resulted being significantly more conducting. By density functional calculations, this observation was suggested to occur due to a single-unoccupaied orbital (SOMO) mediated transport in the case of the open-shell system. Interestingly, at larger bias applied negative differential resistance (NDR) was observed for the fully conjugated closed- and open-shell SAMs (Figure 1).[3] The fact that the LUMO energy level of nonradical PTM is close to the LUMO-α of radical PTM suggests that if a high negative voltage is applied to the tip shifting upwards its work function, resonant conduction through these unoccupied orbitals could take place in both SAMs. Such an effect could account for the NDR peaks. The observation of NDR could be used to perform logic and memory functions in electronic circuits.[4]

References [1] [2] [3] [4]

S. Sanvito. Chem. Soc. Rev., 40 (2011) 3336. N. Crivillers, C. Munuera, M. Mas-Torrent, C. Simão, S. T. Bromley, C. Ocal, C. Rovira, J. Veciana. Adv. Mater., 21 (2009) 1177. N. Crivillers, M. Paradinas, M. Mas-Torrent, S. T. Bromley, C. Rovira, C. Ocal, J. Veciana et al. Chem. Commun.,47 (2011) 4664. I. Kratochvilova, M. Kocirik, A. Zambova, J. Mbindyo, T. E. Mallouk, T. S. Mayer. J. Mater. Chem.,12 (2002) 2927.

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Figures

180 Figure 1: Scheme of the fully conjugated open (SAM 1rad) and closed-shell (SAM 1H) PTM SAMs and their corresponding I窶天 curves as a function of the applied load.


Nanoscale optical hydrophilic characterization Maysoun Douas1,2, M. I. Marqués1, P. A. Serena2 1

Departamento Física de Materiales, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco 28049 Madrid, Spain. 2 Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco, 28049 Madrid, Spain. maysoun.douas@uam.es

Water vapor is generally present in environmental air during experiments development, unless explicit vacuum is required[1]. For surface science, water adsorption in hydrophilic samples is usually stressed, implying nanoscale experimental effects for scanning probe microscope techniques[2]. Scanning Near Field Optic microscope (SNOM), deals with the study of the dielectric properties of matter making use of near field optics[3]. Thus, the humidity presence causes relevant effects, especially when water condensation appears between tip and sample. We combine two simulation methods (FDTD for light propagation and a Lattice-Gas Monte Carlo simulations for water condensation) to study this effect on optical signals detected by a SNOM setup. The results obtained show how the water bridge formation plays an important role not only in the optical image, allowing for the achieving of a high contrast for hydrophilic patches Fig (1), but also in the tip-sample distance control[4]. This work contributes with new data retrieving the original application of SNOM, an instrument able to study the optical properties of matter overcoming the diffraction limit, and extending it to study the hydrophilic character of polymeric and biological samples. References [1] [2] [3] [4]

James, M. et al. Nanoscale condensation of water on self-assembled monolayers. Soft Matt. 7, 5309-5318 (2011). Moing, K. et al. Manipulation of gold nanoparticle: Influence of surface chemistry, temperature, and environment (vacuum versus ambient conditions). Langmuir 24, 1577-1581 (2008). Courjo, D & Bainier, C. Near-Field Microscopy and Near-Field Optics. Rep. Prog. Phys. 57, 9891028 (1994) Taylor, R. S., et al. Damping behavior of bent fiber NSOM probes in water. J. Appl. Phys 107, 043526 (2010).

Figures

Figure 1: (Left) Intensity distribution of the SNOM transmitted signal using two different hydrophilic character samples. (Right) Contrast map of the two samples.

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Process-related mechanical properties of conductive Nanocomposites based on CNT-filled Polypropylen Michael Heinrich, Lothar Kroll, Freddy Sichting Chemnitz University of Technology, Institute of Lightweight Structures, Reichenhainerstrasse 70, 09126 Chemnitz, Germany michael.heinrich@slb.tu-chemnitz.de

The increasing miniaturisation of products including electronic and mechatronic assemblies leads to a maximal integration of functions and developments of manufacturing technologies for very small multicomponent devices. For this purpose the micro injection moulding technology for plastic based micro parts is outstandingly appropriated. This technology is able to produce plastic parts with a high degree of shapefreedom in a high quantity without post processing. The flexibility of this process allows the combination of different materials and the integration of metallic and ceramic inserts as well as electronic or magnetic functional parts [1, 2]. Compared to inherent conductive plastics, filled polymers gain their electrical conductivity through additives, e.g. metals or carbon in different modifications [3]. Depending on volume fraction and filling material, the electrical resistivity can be influenced in a wide range. Especially nano carbon tubes are appropriate to build a conductive network with a low filling material concentration, the so-called percolation threshold [4]. The typical curve of electrical conductivity depending on additive volume fraction shows fig. 1. A characteristic of the injection moulding process is a distinct molecular orientation, which is caused by the flow of polymer melt induced shear and stretching forces [5]. Unlike the extrusion and compression moulding processes, the process forces are high enough to align the additives accordingly [6]. With regard to a shift of the percolation threshold to higher levels of carbon nano tube with an increasing orientation of the additives in the matrix, it is important to minimize this negative influence by a process optimization [7, 8]. The focus of the investigation is the influence of injection speed, melt temperature, cavity temperature and holding pressure were on the orientation of the nano tubes within the polymer matrix. Hence mainly the injection speed and the melt temperature have decisive influence on the mechanical properties and on the conductivity of the composites. Since an increasing injection speed leads to a significant decrease in the yield modulus (fig. 2a), in the strength as well as in the electrical conductivity by several orders of magnitude, an increase of melt temperature leads to improved electrical conductivity but to decrease in the yield modulus (fig. 2b) and also the strength. The influence of the melt temperature is significantly lower compared to the injection speed and the effect of cavity temperature as well as holding pressure is only marginal. Particularly for the PP matrix plastic, these results could be detected with high significance. They thus contradict the well-known phenomenon from the conventional injection molding of an increase in strength with increase in energy input by increasing the focus and distribution of carbon nano tubes within the polymer matrix [8]. It can therefore be assumed that the orientation and distribution of carbon nano tubes have smaller influence on the mechanical properties of the micro-injection molded nanocomposites. As possible causes for the progression of results in micro injection molding, there are two explanations: With the increase of energy input the aspect ratio of carbon nanotubes changes and by increasing the energy input the molecular structure of the matrix resins changes.

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References [1]

[2] [3]

[4]

[5] [6]

[7]

[8]

[9]

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Heinle, C.; Vetter, M.; Brocka-Krzeminska, Z.; Ehrenstein, G. W.; Drummer, D.: Mediendichte Materialverbunde in mechatronischen Systemen durch Montagespritzguss. Kunststofftechnik / Journal of Plastics Technology, Nr. 6, 2009, S. 428-450. Ehrenstein, G. W.; Drummer, D.: Hochgefüllte Kunststoffe mit definierten magnetischen, thermischen und elektrischen Eigenschaften. Springer-VDI-Verlag, 2009. Wong, Y. W.; Lo, K. L.; Shin, F. G.: Electrical and thermal properties of composite of liquid crystalline polymer filled with carbon black. In: Journal of Applied Polymer Science. Bd: 82. (2001), Nr. 6, S. 1549–1555. Kumar, A.; Depan, D.; Singh Tomer, N.; Singh, R.: Nanoscale particles for polymer degradation and stabilization--Trends and future perspectives. In: Progress in Polymer Science. Bd: 34. (2009), Nr. 6, S. 479–515. Johannaber, F.; Michaeli, W.: Handbuch Spritzgießen. München. Hanser, 2002. ISBN 3446156321. Li, Z.; Narh, K. A.: Experimental determination and numerical prediction of mechanical properties of injection molded self-reinforcing polymer composites. In: Composites Part B: Engineering. Bd: 32. (2001), Nr. 2, S. 103–109. Villmow, T.; Pegel, S.; Pötschke, P.; Wagenknecht, U.: Influence of injection molding parameters on the electrical resistivity of polycarbonate filled with multi-walled carbon nanotubes. In: Composites Science and Technology. Bd: 68. (2008), Nr. 3-4, S. 777–789. Abbasi, S.; Carreau, P.; Derdouri, A.: Flow induced orientation of multiwalled carbon nanotubes in polycarbonate nanocomposites: Rheology, conductivity and mechanical properties. In: Polymer. Bd: 51. (2010), Nr. 4, S. 922–935. Domininghaus, H.; Elsner, P.; Eyerer, P.; Hirth, T.: Kunststoffe. Springer Berlin Heidelberg, 2008.

Figures

Figure 1: Electrical conductivity depending on additive volume fraction [9]

Figure 2: a) Yield modulus depends on the injection speed of PP with 5-wt% CNT; b) Yield modulus depends on the melt temperature of PP with 5-wt% CNT


Electrophoretic deposition to develop new optical sensing materials: application to a wireless oxygen sensing microrobot M. Marín Suáreza, S. Medina-Rodrígueza, O. Ergenemanb, S. Panéb, J.F. Fernández Sáncheza, B.J. Nelsonb, A. Fernández Gutiérreza a

Department of Analytical Chemistry, University of Granada, C/Fuentenueva s/n, Granada, Spain b Institute of Robotics and Intelligent Systems, ETH Zurich, Tannenstrasse 3, Zurich, Switzerland mmarinst@ugr.es

Molecular oxygen is one of the most important gases in our environment since it is present in a variety of reactions with industrial, medical and biological applications [1, 2]. In the field of clinical diagnosis and treatments, an inadequate oxygen supply is related with major eye diseases such as diabetic retinopathy, glaucoma, retinopathy, age-related macular degeneration and retinal vein occlusions [3]. However, their relationship is not well known and in vivo oxygen measurements are essential for a better diagnosis and treatment. In this aspect, optical detection of oxygen combined with microrobots offer an interesting tool for in vivo measurement of oxygen concentration inside the eye. Firstly, optical methods are a good alternative towards electrochemical methods due to its advantages such as no oxygen consumption and minimally invasive, among others. In addition to this, wireless microrobots have the potential to revolutionize many aspects of medicine, since they can develop minimally invasive procedures. Therefore, an intraocular optical oxygen sensor using a luminescence coating can be developed with a magnetic platform which is controlled wirelessly with magnetic fields and tracked visually through the pupil, as can be seen in Fig. 1 [4].

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Figure 1: Scheme of the wireless oxygen sensing microrobot.

This sensing microrobot is based on the quenching of luminescence produced by oxygen over a luminescent dye, which is normally deposited on a matrix that acts as coating. Fig. 1 also shows the magnetic microrobot, which was first coated with gold by electroless plating for biocompatibility. In order to obtain the sensing surface it became necessary to develop a method to make surface coating compatible according to the shape and size of the microrobot. To address this issue, gold chips were first used to simulate the gold surface of the microrobot and evaluate the deposition of oxygen sensing nanoparticles by electrophoretic deposition (EPD). This type of film pretends to conjugate the properties of classical polymeric films (in terms of solubility of the dye and selective permeability to oxygen [2]) and the advantages of nanoporous materials (which normally produce a better efficiency of the quenching [5].) Polymeric sensing nanoparticles were produced by precipitation-evaporation method.[6] After optimization, polystyrene-co-maleic anhydride polymer and the oxygen sensitive dye PtTFPP (Platinum tetrakis(pentafluorophenyl)porphyrin) were dissolved in THF and the cocktail was subsequently drop over water under stirring. Monodisperse 140 nm nanoparticles were obtained after the evaporation of the THF, showing a zeta potential of -40 mV.


The EPD was performed straight forward from the solution of nanoparticles, using a self-made electrophoretic cell. The cell consists of a platinum sheet acting as the negative electrode (cathode), a plastic container where the solution is added, and a gold chip, acting as the anode, inserted opposite to the platinum electrode. As the maleic groups of the surface of the sensing nanoparticle are negatively charged, the particles move towards the gold surface when a voltage is applied between the platinum and the gold surfaces. By changing the applied voltage and deposition time it is possible to tune the nanostructured arrays of particles. Therefore, different voltage were applied from 20 V to 5 V, since no deposition was found with lower voltage, while the formed polymer became dark with voltages higher than 20 V. Deposition time was also limited to 15 minutes, since for longer times the darkening of the chip also occurred for all the selected voltages. For each experimental condition, three replicas were done in order to evaluate reproducibility. After the electrophoretic deposition, each gold chip was measure at different oxygen concentration using a fiber optic measurement system based on a phase-modulation technique [7]. The results show good response to oxygen in all the cases, with a slight increased in oxygen sensitivity when lower voltage or times are used. This could be explained by the thickness of the film, which allow the oxygen to better penetrate the pores if the layer is thinner. In fact, as can be observed in the SEM photograph of Fig. 2, the nanoparticles seems to form a single layer, although no total assembly of the particle was reached. This could explain that the sensitivity to oxygen is enhanced when comparing to a film produced by dropping and drying 30 µL of the solution of nanoparticles onto a gold chip.

186 Figure 2: SEM picture of the surface of nanoparticle coated gold chip.

Further optimization of the coating in the real microrobot will be carried out. Nevertheless, electrophoretic deposition of sensitive nanoparticles opens a new field in the development of optical materials that can easily adapt to any surface, regardless of the size and shape, while improving the performance of the sensor, which is of great interest in the development of nanometric scale devices. References [1] [2] [3] [4]

[5] [6] [7]

Y. Amao, Microchimica Acta, 143 (2003) 1. O.S. Wolfbeis, Journal of Materials Chemistry, 15 (2005) 2657. C.A.K. Lange, P. Stavrakas, U.F.O. Luhmann, D.J. de Silva, R.R. Ali, Z.J. Gregor, J.W.B. Bainbridge, American Journal of Ophthalmology, 152 (2011) 406. O. Ergeneman, G. Chatzipirpiridis, F.B. Gelderblom, J. Pokki, S. Pane, M. Marín Suárez del Toro, J.F. Fernández Sanchez, G.A. Sotiriou, B.J. Nelson, Oxygen sensing using microrobots, Engineering in Medicine and Biology Society (EMBC), 2010 Annual International Conference of the IEEE, 2010, p. 1958. J.F. Fernández-Sánchez, R. Cannas, S. Spichiger, R. Steiger, U.E. Spichiger-Keller, Analytica Chimica Acta, 566 (2006) 271. S.M. Borisov, T. Mayr, G.n. Mistlberger, K. Waich, K. Koren, P. Chojnacki, I. Klimant, Talanta, 79 (2009) 1322. C. McDonagh, C. Kolle, A.K. McEvoy, D.L. Dowling, A.A. Cafolla, S.J. Cullen, B.D. MacCraith, Sensors and Actuators B: Chemical, 74 (2001) 124.


Cell behavior by the controlled immobilization of biotinylated proteins in a gradient fashion: non-linear concentration effects produced by unnoticed ligand nanoclustering E. Martíneza,b, A. Lagunasb,a, J. Comellesa,b, S. Oberhansla,b, E. Prats-Alfonsob,d, G. A. Acostab,d, F. Albericiod,e,b, J. Samitiera,b,c a

Nanobioengineering group, Institute for Bioengineering of Catalonia (IBEC),C/ Baldiri Reixac 10-12, 08028 Barcelona, Spain Centro de Investigación Biomédica en Red. Bioingeniería, Biomateriales y Nanomedicina (Ciber-bbn), C/ María de luna 11, Edificio CEEI, 50018 Zaragoza, Spain c Department of Electronics, University of Barcelona, C/ Martí i Franquès 1, 08028 Barcelona, Spain d Institute for Research in Biomedicine (IRB), Barcelona Science Park, C/ Baldiri Reixac 10-12, 08028, Barcelona, Spain e Department of Organic Chemistry, University of Barcelona, C/ Martí i Franquès 1, 08028, Barcelona, Spain emartinez@ibecbarcelona.eu

b

Cell behavior onto bioengineered surfaces, in terms of adhesion, morphology, proliferation and differentiation, is affected by a number of variables including the former substrate derivatization process [1,2]. In this context, it is crucial to avoid uncontrolled exogeneous stimuli as far as possible by using surfaces with immobilized factors presented to the cell in a controlled way. Several examples of biomolecule immobilization strategies onto biomaterials have been described, involving both physical adsorption and chemical binding methods [3,4]. In general, chemical immobilization methods are preferred, since they provide a more stable link between the biomolecules and the biomaterial surface, thus avoiding uncontrolled desorption under physiological environments. However, strong and irreversible immobilization of sensitive biomolecules such as cytokines on surfaces often diminishes their biological functionality. Therefore, chemical immobilization has to ensure that the protein retains its biological activity. Moreover, it has been proven that cell response to many biomolecules is also dose-dependent, thus the biomolecule amount should be the optimal for maintaining its effective local concentration and extend its availability without a systematic risk of high dose. Therefore, it is of primary interest to find strategies that permit the correlation between the concentration of surface-bound growth factors and cell behavior. One of the strategies proposed for the systematic screening of the effects of surface-immobilized biomolecules is the use of the so called surface gradients, surfaces with a gradually varying composition along their length. They can be generated by different methodologies such as controlled diffusion, gradual immersion of the substrate in a reactive solution or microfluidic devices [5,6,7]. However, surface modification for biomolecule anchoring is often accompanied by changes of very relevant surface properties such as wettability, roughness or stiffness, making their effects very difficult to decouple from those coming from the bioactive motives introduced. This work describes a simple method for the construction of universal surface chemical gradient platforms based on the biotin/streptavidin model and its application in cell adhesion and differentiation studies [8]. In this approach, surface chemical gradients were prepared in poly(methyl methacrylate) (PMMA), a biocompatible polymer, by a controlled hydrolysis procedure. The resulting modified surfaces were extensively characterized in their physico-chemical properties. Chemical analysis carried out with time-offlight secondary ion mass spectrometry (ToF-SIMS) and X-Ray Photoelectron Spectroscopy (XPS) showed the formation of a smooth, highly controllable carboxylic acid increasing concentration gradient along the sample surface. Atomic Force Microscopy (AFM) and contact angle (CA) results point out that, in contrast with most of the chemical gradient methods published in literature, the chemical modification performed on the polymer surface barely affects its physical properties. The introduction of carboxylic acid functionality along the surface was then further used for biomolecule anchoring. For this purpose, the surface was allowed the subsequent activation and derivatization with biotin and finally, with streptavidin (SAV) in a directed orientation fashion. SAV gradient was qualitatively assessed by fluorescence microscopy analysis and, later on, quantified by Surface Plasmon Resonance (SPR) technique in order to establish a quantitative relationship between SAV surface densities and surface location. Such a gradient platform was first used to investigate the correlation between cell adhesion and cell-adhesive ligand surface concentration and organization due to substrate modification [9]. For this purpose, RGD

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gradient surfaces were created (Fig. 1). Cell culture shows that adhesion behavior changes in a non-linear way within the narrow range of RGD surface densities assayed (2.8 to 4.4 pmol/cm2) with a threshold value of 4.0 pmol/cm2 for successful cell attachment and spreading (Fig. 2). This non-linear dependence may be explained by a non-homogeneous RGD surface distribution at the nanometer scale, conditioned by the stochastic nature of the hydrolysis process. Atomic Force Microscopy analysis of the gradient surface shows an evolution of surface morphology compatible with this hypothesis. Moreover, the gradient platform was also used to check effects of the concentration of Bone Morphogenic Factor 2 (BMP2) on the osteoblastic commitment of C2C12 cells in a single experiment. The narrow range of BMP-2 surface densities covered by the gradient allows for the precise tracking of the dose-guided activation of osteogenic markers Osterix (OSX) and Alkaline Phosphatase (ALP). A non-linear dependence of cell differentiation response with BMP-2 surface concentration has been found (Fig. 3). We hypothesize that BMP2 ligands, pre-clustered on the surface due to the hydrolysis procedure, can favor ligand-receptor interactions, as reported with integrins, thus enhancing cell signaling.

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References [1] Langer, R.; Tirrell, D. A. Nature 2004, 428, 487-492. [2] Lutolf, M. P.; Hubbell, J. A. Nat. Biotechnol. 2005, 23, 47-55. [3] Maheshwari, G.; Brown, G.; Lauffenburger, D. A.; Wells, A.; Griffith, L. G. J. Cell. Sci. 2000, 113, 1677-1686. [4] Reyes, C. D.; Garcia, A. J. J. Biomed. Mater. Res. A. 2003, 65, 511-523. [5] Lieberg B, Wirde M, Tao Y-T, Tengwall P, Gelius U., Langmuir 1997; 13: 5329-5334. [6] Baker BE, Kline NJ, Treado PJ, Natan MJ, J Am Chem Soc 1996; 118: 8721-8722. [7] Caelen I, Bernard A, Juncker D, Michel B, Heinzelmann H, Delamarche E, Langmuir 2000; 16: 91259130. [8] Lagunas A, Comelles J, Martínez E, Samitier J., Langmuir 2010; 26: 14154-14161. [9] Lagunas A, Comelles J, Martínez E, Prats-Alfonso E, Acosta GA, Albericio F, et al., Nanomedicine: NBM (in press). [10] Lagunas A, Comelles J, Oberhansl S, Martínez E, Samitier J, under review. Figures Figure 1: Scheme of the functionalization procedure followed to fabricate streptavidin gradients. Here, a biotin-PEG-RGD molecule has been attached, but the platform provides a universal mechanism to create gradients of any biotinylated molecules. Figure 2. Cell adhesion in RGD-modified gradients. (a) Phase-contrast micrographs of NIH/3T3 mouse embryonic fibroblasts adhering to the RGDgradient surface after 1 h of incubation at 37°C (number of seeded cells: 2 × 103 2 cells/cm , n = 3). Scale bar, 500 μm. (b) Number of cells adhering as a function of slide distance, showing a sharp increase in the cell adhesion number for RGD surface densities larger than 4.0 pmol/cm2. Figure 3: Tracking OSX activation and translocation into the cell nuclei as an effect of surface density. (A) Representative immunofluorescent images of C2C12 cells fixed and immunostained for OSX after 24h in culture at different positions on the BMP-2 gradient. Scale bar = 50 µm. (B) Plot of the OSX distribution percentages (selected following the Polak and coworkers criteria) as a function of the slide position (from the less hydrolyzed part of the slide). At least 30 cells were evaluated per selected region in three independent experiments.


Preparation of graphenic materials of different structure Rosa Menéndez, Cristina Botas, Clara Blanco, Marcos Granda, Ricardo Santamaría and Patricia Alvarez Instituto Nacional del Carbón, CSIC, Apartado 73, 33080 Oviedo, Spain rosmenen@incar.csic.es

A summary of the activities of the Composites Group in the field of graphenic materials is presented. These activities include: i) the use of the chemical route through the oxidation of graphites of very different crystalline structure to obtain graphene oxides; ii) the reduction of the graphene oxides by thermal treatment, with hydrazine or with hydrogen and iii) the mechanical exfoliation of highly crystalline graphites. A detailed study on the structural changes of the different materials in the whole chain graphite-graphite oxide-graphene oxide-reduced graphene oxide by spectroscopic (Raman, FTIR, XPS, Xray diffraction) and microscopy techniques (SEM, TEM, HR-TEM, AFM) provide novel information about the effect of the parent graphite and processing conditions on the characteristics of graphenic materials. Two different approaches can be used to prepare graphene: the so-called top-down and bottom-up methods [1]. The top-down strategy involves carbon sources of a large size that are cut into graphene nanoplatelets. Examples of these are to be found in the mechanical cleavage of graphite[2,3], the exfoliation of graphite (via graphite oxides and intercalation compounds, so-called chemical approach)[4] or the longitudinal unzipping of carbon nanotubes[5]. This work describes the approaches used by our group to produce graphenic materials with different characteristics. Graphenes obtained by successive peeling of highly oriented graphites with different angular spread of the crystallite c-axes have shown an excellent behaviour as components in microwave frequency multiplication systems[6]. This work is part of collaboration with the Department of Electrical Engineering at the University of Oviedo. The advantage of this method is that it yields graphene layers of a high quality. The size and shape of the graphene flakes are heavily dependent on the graphite’s crystalline structure. Its main limitation is related to its scalability, and to date it has only been used in fundamental laboratory studies. The exfoliation of graphite to produce graphene oxide (based on the Hummers[7], Brodie[8] or Staudenmaier[9] methods) is nowadays the most widely applied top-down strategy for the preparation of graphenic materials of different structure, mainly due to its scalability and low cost. By using specifically prepared graphites from the same precursor with controlled crystal properties, it was demonstrated experimentally that the crystalline structure of the initial graphite has a marked influence on the atomic structure of graphene oxides and also on the average area of the sheets. [10] The reduction of graphene oxides is required in order to produce thinner flakes through the elimination of the oxygen functional groups (heat treatment, hydrogen, hydrazine, etc) [11,12]. In collaboration with Catalonia Institute for Energy Research (IREC) and the Institute of Materials Science of CSIC in Barcelona (ICMB), we have studied the effect of graphene oxide atomic structure (degree of structural perfection, type of oxygen functional groups and location) on its behaviour upon reduction with hydrazine, and on the characteristics of resultant reduced graphene oxides. It was experimentally proved the theoretical model of Gao et al[13] who claim that deoxygenation is more effective when the oxygen functional groups are located in the interior of the aromatic domains than when located at the edges. The reduced graphene oxides exhibited a very different atomic structure and stacking tendency (Figure 1). The location of the remaining hydroxyl groups at the edges in one of the materials propitiated lateral interactions which brought about a substantial increase in the size of the sheets. Furthermore, in collaboration with ITQ-CSIC, the graphene structure was restored after the chemical reduction, through the reconstruction of the C sp2-hybridized bonds with carbon monoxide.[14]

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Exfoliation and thermal reduction of graphene oxides offers a simple and clean way to obtain graphenes. We have performed studies on the effect of temperature (from 120 º C to 2,400 º C), on the exfoliation/reduction behaviour of graphite oxides (Figure 2), determining the critical temperatures that affect the efficiency of the process and quality of the products. The results obtained show that the exfoliation temperature and the effectiveness of the thermal reduction are largely dependent on the chemical structure of the graphene oxide (type of functional groups and location) which in turn depends on the characteristics of the parent graphite. Moreover, employing temperatures above 1000 ºC improves the structural order of the graphene sheets although facilitates their stacking References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10]

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[11] [12] [13] [14]

Luo B, Liu S, Zhi L, Small, 25 (2011) 1. Lu XK, Yu MF, Huang H, Ruoff RS, Nanotechnology, 10 (1999) 269. Geim AK, Novoselov KS, Nature Materials, 6 (2007) 183. S. Stankovich et al., Nature, 422 (2006) 282. Kosynkin DV, Higginbotham AL, Sinitskii A, Lomeda JR, Dimiev A, Price BK, Tour JM, Nature, 2009, 872. G. Hotopan, S. Ver Hoeye, C. Vázquez, R. Camblor, M. Fernández, F. Las Heras, P. Álvarez, R. Menéndez, Progress In Electromagnetics Research, 118 (2011) 57. Hummers W, Offeman R, J. Am. Chem. Soc., 80 (1958) 1339. Brodie BC, Ann. Chim. Phys., 59 (1860) 466. Staudenmaier L, Ber Dtsch Chem Ges, 31 (1898) 1481. Botas C, Álvarez P, Blanco C, Santamaría R, Granda M, Ares P, Rodríguez-Reinoso F, Menéndez R. Carbon, 50 (2011) 275. Stankovich S, Piner R D, Chen X, Nguyen S T, Ruoff R S, J. Mat. Chem., 16 (2006) 155. Kaniyoor A, Baby TT, Ramaprabhu S, J. Mat. Chem.,20 (2010) 8467. Gao, X.; Jang, J.; Nagase, S. J. Phys. Chem., 114 (2010) 832. Pulido A, Concepción P, Boronat M, Botas C, Alvarez P, Menendez R, Corma A, J. Mat. Chem. (2012), in press

Figures

Figure 1: TEM (a) (d), AFM (b) (e) images and XPS 1CS results (c) (f) showing twopartially reduced graphene oxides obtained from graphites of different crystallinity.

Figure 2: XRD results showing the variation of Lc and d(002) of thermally reduced graphene oxides with temperatures.


Optical biosensors based on graphene Eden Morales-Narváez1,2, Briza Pérez-López1,3, Arben Merkoçi*,1,4 1

Nanobioelectronics & Biosensors Group, Catalan Institute of Nanotechnology, CIN2 (ICN-CSIC), Barcelona, Spain. 2 Polytechnic University of Catalonia, ESAII department, Barcelona, Spain, 3 LEITAT Technological Center, Barcelona, Spain. 4 ICREA, Barcelona, Spain. *arben.merkoci@icn.cat

Since graphene bears innovative mechanical, electrical, thermal and optical properties, this twodimensional material is under active research [1–7]. In this regard, graphene displays advantageous characteristics to be used in biosensing platforms owing to the excellent capabilities for direct wiring with biomolecules, heterogeneous chemical and electronic structure, the possibility to be processed in solution and the availability to be tuned as insulator, semiconductor or semi-metal [3,6,8,9]. Moreover, after oxidation treatments, graphene can exhibit an interesting photoluminescence property in relation to resonance energy transfer donor/acceptor molecules exposed in a high planar surface and even can be proposed as a highly efficient quencher, which is opening the way to new biosensing strategies. We will discuss some exploitable properties of graphene in optical biosensig and our experimental results of the excellent capabilities of oxidized graphene as fluorescence quencher in order to be employed in biosensing applications. Graphene based optical biosensing platforms are versatile in configurations in addition of being highly sensitive, robust enough beside offering interesting multidetection capabilities in association to other nanomaterials (i.e. quantum dots). The preliminary results obtained so far seems to be with interest for future applications such as diagnostics (biomarkes detection) or safety and security applications (i.e. bacteria). References [1] [2] [3] [4] [5] [6] [7] [8] [9]

S. Park, R. S. Ruoff, Nature nanotechnology 2009, 4, 217-24. O. C. Compton, S. T. Nguyen, Small 2010, 6, 711-23. K. P. Loh, Q. Bao, G. Eda, M. Chhowalla, Nature chemistry 2010, 2, 1015-24. Y. Zhu, S. Murali, W. Cai, X. Li, J. W. Suk, J. R. Potts, R. S. Ruoff, Advanced materials 2010, 22, 3906-24. K. S. Novoselov, Angewandte Chemie (International ed. in English) 2011, 6986 - 7002. Y. Wang, Z. Li, J. Wang, J. Li, Y. Lin, Trends in biotechnology 2011, 29, 205-12. F. Schedin, a K. Geim, S. V. Morozov, E. W. Hill, P. Blake, M. I. Katsnelson, K. S. Novoselov, Nature materials 2007, 6, 652-5. M. Pumera, Materials Today 2011, 14, 308-315. A. Bagri, C. Mattevi, M. Acik, Y. J. Chabal, M. Chhowalla, V. B. Shenoy, Nature chemistry 2010, 2, 581-7.

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Assessing ionic silver availability to algae from differently coated silver nanoparticles Enrique Navarro1*, Bettina Wagner2, Niksa Odzak2, Laura Sigg2 and Renata Behra2 1

Instituto Pirenaico de Ecología (CSIC), Av. Montañana 1005, Zaragoza 50059, Spain 2 Eawag, Überlandstrasse 133, Postfach 611, 8600 Dübendorf, Switzerland enrique,navarro@ipe.csic.es

Introduction Because its biocide properties [1-4], silver nanoparticles (AgNP) are present in numerous consumer products. Toxicity of AgNP to organisms is related with both the formation of ionic silver (Ag+) and interactions between AgNP and Ag+ with cell membranes [1-3]. Hence, studies on AgNP toxicity are challenged by understanding the contribution of these causes to the whole toxicity [5]. Thus, characterization of AgNPs in toxicity experiments also requires determining the bioavailable concentration of ionic silver. At present methodological limitations result in under estimation of readily bioavailable ionic silver, especially if ionic silver is formed at nanoparticles-cell interface and is immediately taken up by cells [3]. In addition, nanotechnological development relies not only in nanomaterials synthesis but in functionalization of their surfaces, adding more complexity to these studies. In this case, the availability of ionic silver might be strongly determined by the chemistry of the different products used as a coating. In this work we propose a method to examine the role of Ag+ in explaining toxicity of differently coated AgNPs to algae, by using cysteine to assess Ag+ bioavailability. We thus assessed the toxicity of AgNPs coated with 5 different chemicals, on the photosynthesis of Chlamydomonas reinhardtii. Experiments in presence of cysteine which is a strong Ag+ ligand was used to estimate the amount of Ag+ present in the exposure media. From our previous work on AgNP toxicity [3] we hypothesize: a) the importance of Ag+ to explain the toxicity of AgNP and b) toxicity to photosynthesis might help us to assess the ionic silver readily bioavailability for algae. This approach allows us to estimate ionic silver bioavailable for algae, overcoming methodological limitations associated to the use of direct chemical analysis. Results Experiments were carried out using 5 different AgNP, coated with carbonate -CO3-, polyetheleneglycol PEG-, lactate -LAC-, chitosan -CHI- and polyvinyl pyrrolidone -PVP-. Toxicity of AgNP to photosynthesis was assessed by concentration-response experiments exposing algae to increasing concentrations of the different AgNP (Tab. 1). Algal photosynthetic yield was measured over 1 hour exposure time by fluorometry [3]. AgNP CO3 PEG LAC CHI PVP

% of Ag+ 1 16,2 9,2 3,7 20

EC50 (μM Agtot) 2,98 1,29 2,15 2,84 0,78

EC50 (μM Ag+) 0,030 0,209 0,199 0,106 0,154

μM Cys 0,405 0,420 0,510 0,500 0,491

Table 1: AgNP’s EC50 have been calculated as a function of the total Ag present in the suspensions, as a function of Ag+ present (calculated using chemical analysis). Last column shows the amount of Cysteine required to completely abolish the toxicity of EC50.

Based on total Ag concentration (Tab. 1), AgNP EC50 ranged from 0,78 to 2,98 μM (Tab. 1). Cysteine completely abolished AgNP toxicity (previous experiments, data not shown), indicating that toxicity was

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mediated by Ag+ and at the same time that different coatings were not toxic to photosynthesis. Hence, it was expected that EC50 values calculated as a function of the Ag+ present in the experimental suspensions (assessed using chemical analysis) would converge to similar values. But, these values (Tab.1) showed again a wide range of variation (from 0.03 to 0.2).

Figure 1: Effect of increasing cysteine concentrations on the toxicity of AgNPs EC50. The cysteine required to abolish toxicity was calculated as the intersection of every curve with the 100% line.

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Then, we considered the possibility that Ag+ concentration used to calculate EC50 was underestimated (see introduction). We calculated the cysteine concentration required to completely abolish toxicity of AgNPs EC50, as an estimate of bioavailable Ag+ (Fig.1). Cysteine concentrations needed to completely abolish AgNP toxicity showed similar values for all AgNP, regardless their coatings (from 0,405 to 0,500 ÎźM). This experiment strongly suggested that Ag+ bioavailable to algae was in all cases around 0,4-0,5 ÎźM (cysteine binds Ag+ in 1:1 stoichiometry). Together, results indicate that chemical analyses are not enough to characterize exposure conditions. Use of cysteine and algal photosynthesis might be a helpful control method, especially when dissolved metals might be released or formed upon nanoparticles-cell interface interactions. References [1]

[2]

[3]

[4]

[5]

Pal, S., Y.K. Tak, and J.M. Song, Does the antibacterial activity of silver nanoparticles depend on the shape of the nanoparticle? A study of the gram-negative bacterium Escherichia coli. Applied and Environmental Microbiology, 2007. 73(6): p. 1712-1720. Panacek, A., L. Kvitek, R. Prucek, M. Kolar, R. Vecerova, N. Pizurova, V.K. Sharma, T. Nevecna, and R. Zboril, Silver colloid nanoparticles: Synthesis, characterization, and their antibacterial activity. Journal of Physical Chemistry B, 2006. 110(33): p. 16248-16253. Navarro, E., F. Piccapietra, B. Wagner, F. Marconi, R. Kaegi, N. Odzak, L. Sigg, and R. Behra, Toxicity of Silver Nanoparticles to Chlamydomonas reinhardtii. Environmental Science & Technology, 2008. 42(23): p. 8959-8964. Navarro, E., A. Baun, R. Behra, N.B. Hartmann, J. Filser, A.J. Miao, A. Quigg, P.H. Santschi, and L. Sigg, Environmental behavior and ecotoxicity of engineered nanoparticles to algae, plants, and fungi. Ecotoxicology, 2008. 17(5): p. 372-386. Kim, J.S., E. Kuk, K.N. Yu, J.H. Kim, S.J. Park, H.J. Lee, S.H. Kim, Y.K. Park, Y.H. Park, C.Y. Hwang, Y.K. Kim, Y.S. Lee, D.H. Jeong, and M.H. Cho, Antimicrobial effects of silver nanoparticles. Nanomedicine-Nanotechnology Biology and Medicine, 2007. 3(1): p. 95-101.


Need for guidelines specifically adapted for the toxicity testing of nanomaterials Porredon, C1, de Lapuente, J1, Ramos-López, D1, De Marzi, L2, Minatta, V3, González-Linares, J1, Brull N1 and Borràs M.1 1

Unitat de Toxicologia Experimental i Ecotoxicologia. Parc Científic de Barcelona. Baldiri i Reixac 10-12; 08028-Bacelona. España 2 Dipartimento di Biologia di base ed applicata, Facoltà degli Studi dell’Aquila, Italia 3 Stagiaire in the Leonardo Unipharma grant, Italia jlapuente@pcb.ub.cat

In the last two decades the scientific world has been involved in what we can call a Nanorevolution. Thanks to their surprising and promising physical and chemical properties, nanoparticles (NPs) have attracted the attention of scientists in different fields such as Electronic, Mechanic, Biomedicine and Diagnosis. In this way, the aim of the researchers is the development of appealing devices for a widespread range of applications. However, this could mean that the use of NPs for commercial products will let these nanomaterials get in contact with Humans and Environment in a dose/time concentration ratio higher than the expected one. Moreover, the possible reactions and the effects that NPs can induce in human’s health are still unknown. Due to the starting use of NPs in commercial products, from electrical devices to food additive, and the increasing attention and warning of the consumers, the European Governments and the EE UU have focused their attention on the “NPs safety issue” in the last decade. Nowadays, there are lots of validation tests to estimate and evaluate the impact of NPs in the humans and the environment. These tests include in vitro, in vivo and ecotoxicological assays and, thanks to the results obtained, it is possible to have a general overview on the possible impact of nanocompounds. The problem, anyway, is that the results obtained till now are chaotic and not well organized, due the lack of standard procedure protocols. That is the reason why the European Commission has located financial grants in the last Seventh Framework Program (NMP.2012.1.3-3 Regulatory testing of nanomaterials) to develop a way of standardized and put an order on the nanomaterial world. To help the understanding of the NPs interactions with cells and living systems, some groups of scientists are now using the QSAR ideas of the computational approach and have developed the so-called quantitative nanostructure-activity relationships (QNAR) modeling (Fourches et al., 2011). In this work, we focus our attention on the difficulties in understanding the behavior that NPs can have into a living system. In our laboratory we have made in vitro and in vivo tests on different types of NPs: gold (with and without coating and with different sizes), cobalt ferrite, cerium oxide and graphene oxide NPs. The first step was to perform in vitro tests of NPs taking into account size, chemical nature and eventual coating to evaluate the possible internalization, cytotoxicity, genotoxicity and embryotoxicity. The results show different effects depending on the type, size and coating (di Guglielmo et al., 2010) (Fig1). We performed a wide in vivo analysis (in Rattus novergicus) by exposing the animals to three types of NPs: gold NPs with and without coating and cobalt ferrite NPs. The obtained results showed differences in kinetic behavior and in deposition in different organs (Fig 2). In particular, the inhalation exposure to gold NPs for 21 days demonstrates the presence of pneumoconiosis in all treated groups. On the other side, cerium oxide NPs seems to alterate the DNA structure in the in vitro tests inducing genotoxic effects. Interestingly, these NPs in the presence of a well known oxidant compound are able to protect the cells from oxidative stress damages due to its chemical nature.

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Seed germination test was performed to evaluate ecotoxicity of these NPs. Different effects were obtained according to different plant species tested. It was especially noticeable that smaller seeds showed a higher level of toxic effects than the bigger ones at the same concentration of nanoparticles. Even graphene oxide NPs showed interesting results. This nanomaterial seems to be very well tolerated by cells as we have tested its cytotoxicity with MTT tests and it revealed no acute toxic effect. Anyway, it can produce a decrease in the % of viability when considering a chronic effect. Concerning genotoxicity, a very high toxic response was obtained as it can be compared to the positive control used in the comet assay. What we would underline is to focus the general attention on the characteristics, behavior and way of interactions of the NPs in the living systems and how these factors should be taken into consideration when we analyze the toxicological results. Particular factors such as distribution, internalization and surface coating can modify the fate of NPs in the cells. Differences in size, shape, coating and chemical nature increase the difficulty level for a unique, linear and coherent understanding of the results. Finally, since the industrial and biomedical industries has a need for standards and well fixed parameters, it’s necessary to start establishing the basis for a European guideline that should be followed Europewide. This project has been co-funded by MICINN and ERDF NanoSost, towards a sustainable, responsible and safe nanotechnology PSE–42000–2008–003 References

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Fourches, D, Pu, DQ and Tropsha, A. Combinatorial Chemistry and High Throughput Screening 14 (2011): 217-225 Claudia Di Guglielmo, David Ramos López, Joaquín De Lapuente, Joan Maria Llobet Mallafre Miquel Borràs Reproductive Toxicology 30 (2010) 271–276 C. Porredon, D. Ramos, J. De Lapuente, L. Camps, M. Borràs Toxicology Letters, 196 (2010): S280S281

Figures

Figure 1: Histogram of the potential degree of toxicity in embryos with the in vitro Embryonic Stem Cell Test.

Figure 2: Results of in vivo assays for blood kinetic (left) and body biodistribution of NPs (right).


Assessment of nanoceria toxicity in aquatic photosynthetic organisms Ismael Rodea-Palomares1, Soledad Gonzalo2, Javier Santiago2, Francisco Leganés1, Eloy García-Calvo3, Roberto Rosal2,3, Francisca Fernández-Piñas1 1

3

Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid. E-28049, Madrid, Spain 2 Departamento de Ingeniería Química, Universidad de Alcalá, E-28871, Alcalá de Henares, Madrid, Spain Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805, Alcalá de Henares, Madrid, Spain francisca.pina@uam.es

The commercial applications of engineered nanoparticles (ENPs) have widely expanded over the last years with subsequent increased release into the environment. The particular physicochemical properties of nanoparticles with regards to the same non-nano compound have raised serious concerns about their potential environmental risks. Algae and cyanobacteria are ecologically relevant organisms which are at the base of aquatic food webs and have essential roles in nutrient cycling; both are ideal models to study potential effects of released ENPs. Cerium oxide nanoparticles, which have widespread applications, are interesting nanomaterials due to their unique redox properties which are based in the mixed valence state of CeO2 (Ce3+ and Ce4+). Our group have reported that nanoceria exhibited strong toxicity to the green alga Pseudokirchneriella subcapitata and the cyanobacterium Anabaena CPB4337; in both organisms nanoceria exposure resulted in highly damaged cells with extensive membrane disruption [1]. We found no evidence of nanoparticle uptake by cells, but our observations suggested that their toxic mode of action required direct contact between nanoparticles and cells; in the case of the cyanobacterium, cells completely coated by layers of ceria nanoparticles were observed [1]. Free cerium was highly toxic for both organisms but the negligible amount found dissolved in the nanoparticle suspensions could not explain the observed toxic effect of nanoceria on the aquatic organisms [1]. In order to to gain insights into the mechanisms of the observed toxicity by nanoceria, the main bioenergetic process of these organisms, photosynthesis, was studied both by measuring oxygen evolution and chlorophyll a fluorescence emission parameters. Nanoceria significantly inhibited photosynthesis in the cyanobacterium in the whole range of concentrations tested (0.01 to 100mg/L); a dual effect of nanoceria was found in the green alga with slight stimulation at low concentrations and strong inhibition at the highest concentrations tested; chlorophyll a fluorescence experiments indicated that nanoceria had a significant impact on the primary photochemical processes of photosystem II (Fig. 1). The primary cause of the observed photosynthetic inhibition by nanoceria could be an excessive level of ROS formation; the results indicated a strong generation of reactive oxygen species (ROS) as indicated by an increase in DCF fluorescence, a general oxidative stress indicator (Fig. 2) which caused oxidative damage in both photosynthetic organisms. It is proposed that nanoceria increase the production of hydrogen peroxide (a normal ROS by-product of light-driven photosynthesis) in both the green alga and cyanobacterium; this ROS, through a Fenton-like reaction, may increase lipid peroxidation, compromising membrane integrity and also seriously impairing photosynthetic performance, eventually leading to cell death.

Acknowledgements This work was funded by Comunidad de Madrid grants S-0505/AMB/0321 and S2009/AMB/1511 (Microambiente-CM) and by the Spanish Ministry of Science and Innovation [grant CGL2010-15675, sub-programme BOS].

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References [1]

Rodea-Palomares I, Boltes K, Fernández-Piñas F, Leganés F, García-Calvo E, Santiago J and Rosal R. Toxicological Sciences 119 (2011): 135-145.

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Figure 2: Flow cytograms of cell/filament complexity (SS) as a function of cell/filament size (FS) and corresponding DCF fluorescence histograms of Anabaena CPB4337 (A) and P. subcapitata (B) exposed for 72 h to CeO2 nanoparticles. Cell/filament subpopulations were identified based on size and complexity: AI = main subpopulation (green dots), N = subpopulation which included cells/filaments with the highest size, complexity and DCF fluorescence signal (red dots) and J = Cells/filaments with the smallest size/complexity and/or cell debris (blue dots).


Intermolecular H-Bonding for Porphyrin Molecules on Surfaces: experimental evidences and theoretical investigation A. Garcia-Lekue,1 R. González-Moreno,1,2 S. Garcia-Gil,3 L. Floreano,4 A. Verdini,4 A.Cossaro,4 J. A. Martin-Gago,5 A. Arnau,1,2,6 and C. Rogero1,2 1

Donostia International Physics Center (DIPC), San Sebastian, Spain, Centro de Física de Materiales (CSIC-UPV/EHU), Materials Physics Center MPC, San Sebastian, Spain, 3 Centre d’Elaboration de Matériaux et d’Etudes Structurales (CEMES), Toulouse, France, 4 Istituto Officina dei Materiali (CNR-IOM), Laboratorio TASC,Trieste, Italy, 5 Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Madrid, Spain, 6 Departamento de Física de Materiales UPV/EHU, Facultad de Química, San Sebastian, Spain celia_rogero@ehu.es, wmbgalea@ehu.es

2

The study of the chemical bond of adsorbates on and with surfaces is of particular importance for new widespread developments, from healthcare to electronics or environment. In most cases these interactions are weak and they can be considered in the context of supramolecular chemistry, which studies the organization of systems based on weak and reversible non-covalent interactions. Among them, hydrogen bond is one of the most important. It is defined as X-H⋯Y where the H atom is in between another two, X and Y, and acts like a bridge between them. X and Y can be the same or different elements and depending on their nature the strength of the bond varies. Thus, bonds of the type C-H⋯F are one of the weakest interactions whereas it has been demonstrated that the most strongest, ubiquitous and persistent H-bonds are those formed between O and N atoms in the carboxylic acids and pyridine groups (therefore N-H⋯O-C or C-O-H⋯N). [1] In the present work we detect the formation of this type of H bond for porphyrin molecules adsorbed on metal surfaces. Particularly, by the comparison of the experimentally observed shifts of the core-levels with first principle calculations, it is possible to identify the nature of the interaction of protoporphyrin IX molecules (H2PPIX) evaporated on Cu surfaces at low-temperature By X-ray photoelectron spectroscopy (XPS) it was observed that the shape of the N 1s core level of H2PPIX evaporated on Cu surfaces at low temperature (around 200K) was different than the expected one: the component related to the N atoms in a N-H form is higher than expected [2]. Figure 1 illustrate this effect comparing the N1s of the H2PPIX power with the H2PPIX adsorbed on Cu(110). The ab-initio calculation of the XPS core level shift (CLS) [3] determines the new intermolecular interactions for H2PPIX on Cu surfaces. Calculated values of CLS of the order of 2eV explain the formation of bonds: covalent H-N Hbonds as well as N-H⋯O-C H bonding between the carboxylic group and the pyrrolic ring of adjacent molecules has been revealed. Moreover, the unexpected high value of the CLS for H-bonding gives a relation between H-bond strength and shifts in the core level position: as higher the core level, stronger the hydrogen bond. Thus, since CLS are strongly affected by the local and chemical environment of each atom, valuable information on the conformation of the system can be extracted by calculating core-level shifts and comparing them to measured XPS spectra.

199


References [1] [2]

[3]

Weyna, D. R.; Shattock, T.; Vishweshwar, P.; Zaworotko, M. J. Crystal & Growth Design 2009, 9, 1106; Desiraju G. R. Acc. Chem. Res. 2002, 35, 565 González, R.; Sánchez-Sánchez, C.; Trelka, M.; Otero, R.; Cossaro, A.; Verdini, A.; Floreano, L.; Ruiz-Bermejo, M.; Garcia-Lekue, A.; Martín-Gago, J. A.; Rogero, C. J. Phys. Chem. C 2011, 115, 6849; Garcia-Lekue A., González-Moreno R., Garcia-Gil S., Floreano L., Verdini A., Cossaro A., Martin-Gago J. A., Arnau A., and Rogero C. Submitted. Pehlke, E.; Scheffler, M. Phys. Rev. Letters 1993, 71, 2338; Soler, J. M.; Artacho, E.; Gale, J. D.; Garcia, A.; Junquera, J.; Ordejón, P.; Sanchez-Portal, D. J. Phys.: Condens. Matter 2002, 14, 2745; Garcia-Gil, S. Theoretical Characterization of Metallic and Semiconducting Nanostructures by means of DFT using Localized Basis Sets. Ph.D. thesis, Universitat Autònoma de Barcelona, 2011.

Figures

200

Figure 1: Experimetnal N 1s core levels of the H2PPIX in powder (top) and H2PPIX on Cu(110) (bottom)and the calculated CLS for both different N environments. The molecules adsorved on the surface exhibit the formation of H bonds (covalent H-N H-bonds as well as N-HO-C H bonding


Nanotechnology in the Hemostasis Laboratory Dr. Miguel Roncales Poza mroncales@alphasip.es

Nanotechnology is the study, design, creation, synthesis, manipulation and application of materials, devices and functional systems through the control of nano-scale material and the exploitation of the phenomena and properties of this nano-scale material (1 to 100nm/ 1nm= 10-9). [1] The latest advances in atomic-scale research have fostered the awakening of a new discipline known as Nanomedicine. This emerging discipline consists of the application of techniques that come from the Nanotechnology field to human health. Nanomedicine covers all medical practices, including prevention, diagnostics and therapy, which require technologies based on the interaction between the human body and materials, structures or devices whose properties are defined at nano-scale. [2] Nanomedicine, in its nanodiagnostics aspect, offers great opportunities in early diagnostics and monitoring of different disorders such as cardiovascular diseases and hematological diseases. Nanobiosensors are analytical devices that turn a biological response into an electrical signal. They are composed of a biological element (analyte) and a physical element (a transducer which translates the results of the biological response into electrical signals). The biological part of the sensor is formed by a coating that usually contains a receptor layer fixed to the transducer by different types of bonding (adsorption, covalent bond, polymeric, etc.). The receptors bind specifically to the target analyte resulting in modifications which are transformed into electrical signals. The transducer is the element in charge of detecting the signal derived from the biological reaction. Carbon Nanotubes (CNTs) are transducer elements highly studied in the past years due to their exceptional properties. CNTs are the strongest fibers known. One single perfect nanotube is 10 to 100 times stronger than steel (weight per unit) and have very interesting electrical properties, conducting electrical current hundredths of times more efficiently than traditional copper cables. [3] The inherent properties of CNT’s together with their easy incorporation in an electrode, have promoted their use in numerous electroanalytical and bioelectroanalytical applications. The sensibility of the nanobiosensors based on CNTs is much higher than conventional sensors, favoring fast and efficient diagnostics. Currently, nanotechnology and nanomedicine are focusing on molecular biology which makes it possible to design electrical microchips capable of identifying, in only eight minutes, and with a single drop of blood, the patient’s illness, his family history and even which diseases he could suffer in the future. [4] Nanobiosensors based on carbon nanotubes have a promising application in the field of Hematology and Hemostasis. There is a great interest incorporate, to daily routines, chips that allow the doctor’s to work at Point of Care, with only a drop of capillary blood. With these devices one can measure antibody-antigen reactions with a sensibility and specificity much higher than current techniques such as ELISA (EnzymeLinked ImmunoSorbent Assay) and furthermore, detect modifications in DNA, i.e. genetic mutations. In the Hemostasis and Thrombosis laboratory nanotechnology chips, as the ones aforementioned, can be introduced to determine different profiles which are usually studied in these types of laboratories: TromboSIP® allows the determination of a thrombophilic profile, by measuring Antithrombin and Factor V Leiden, amongst other factors.

201


TAO Chip® cann be employed in the treatment with antivitamin K. The INR determination can be substituted by PC (Prothrombin Complex) or others. These factors suppress Antivitamin K, not like INR that measures Factor V which isn’t Vitamin K dependent but not Factor IX which is. [5] These two examples are just a small representation of the possibilities that portable nanobiosensors offer in the hemostasis laboratory. Some advantages of these devices are: fast and precise diagnostics that only require one test and simple monitoring which helps clear emergency departments and accelerates treatment application. Finally, it is necessary to keep in ming that the industry is struggling to satisfy the emerging demands of the diagnostic field, increasingly decentralized, promoted by the need of achieving more productivity and efficiency in healthcare, reducing waiting lists and the lack of beds in the hospitals, and –without doubt- to improve disease management. [6] Nanobiosensors are the response to the demands of a decentralized diagnostic system, offering diagnostics where and when needed. References [1] [2] [3] [4]

202

[5] [6]

Clavijo D., García G., et al. De las nanopartículas a los nanodispositivos. Universitas Médica. 2006;46:134-7 González, J. M., López, M .y Ruiz, G.; Informe de Vigilancia Tecnológica en Nanomedicina. Circulo de Innovación en Biotecnología, Comunidad de Madrid, 2007 Biosensing using nanomaterials. Arben Merkoçi. John Wiley & Sons, Inc New Jersey, 2009 Applications of carbon nanotubes in drug delivery. 2005. Alberto Bianco, Kostas Kostarelos and Maurizio Prato. Current Opinion in Chemical Biology 9, 674-679) www.alphasip.es Kalorama; Point of Care Diagnosticis, November 2009.


Compressed fluids: unique media for preparing vesicles with high structural homogeneity Elisa Elizondo, Ingrid Cabrera, Evelyn Moreno, Lidia Ferrer, Mildrey Sánchez, Jaume Veciana*, Nora Ventosa* Department of Molecular Nanoscience and Organic Materials. Institut de Ciència de Materials de Barcelona (ICMABCSIC), Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, Campus de la Universitat Autònoma de Barcelona (UAB), 08193-Bellaterra (Spain) ventosa@icmab.es; vecianaj@icmab.es

Vesicles are nano/microparticulate colloidal carriers, usually 0.05-5.0 µm in diameter, which form spontaneously when certain lipids are hydrated in aqueous media. They consist of a small enclosed liquid compartment separated from its surroundings by one or more lipid bilayers. In particular, small unilamellar vesicles (SUVs) have gained a lot of attention in the drug delivery field because they can be used as smart nanocapsules with a precise response to external stimuli and can be functionalized to obtain active drug delivery systems [1]. Despite their versatility, a high degree of structural homogeneity is crucial for an optimal performance of vesicles as drug delivery carriers. Thus, the formation stage of these supramolecular entities must be tightly controlled in order to achieve a homogeneous self-assembling of the lipids constituting the vesicular membrane [2]. In this sense, compressed fluids (CFs) like compressed CO2 have a great deal of promise as solvent media for material processing, since their unique characteristics between those of liquid and gases, allow the achievement of materials presenting highly homogeneous structure [3]. In this communication will be shown the influence of the preparation route on the assembly of lipids as vesicles and the potential of CF-based methods for providing more homogeneous non-crystalline ordered materials [5,6]. References [1] [2] [3] [4] [5]

R Sawant, V. Torchilin., Soft Matter 2010 6, 4026 G.M. Whitesides, B. Grzybowski,. Science 2002, 295, 2418. J.D. Holmes, K.P. Johnston, R.C. Doty, B.A. Korgel, Science 2000, 287, 1471 M. Cano-Sarabia, N Ventosa, S.Sala, C. Patino, R. Arranz,; J. Veciana Langmuir 2008, 24, 2433. E. Elizondo, J. Larsen, N. S. Hatzakis,I. Cabrera, T. Bjørnholm, J. Veciana, D. Stamou, N. Ventosa, J.Am.Chem. Soc. 2012 134, 1918.

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204


An electrochemical competitive biosensor for fumonisin B1 (FB1) based on a DNA biotinylated aptamer JC. Vidal1, L. Bonel2, JR. Castillo1 and A.Ezquerra1 1 Institute of Environmental Sciences (IUCA) Analytical Spectroscopy and Sensors Group (GEAS) University of Zaragoza. Ciudad Universitaria, 50009, ZARAGOZA. Spain 2 CAPHER IDI S.L, C/Ermesinda de Aragón, 4, nº116, 50012, ZARAGOZA, Spain jcvidal@unizar.es

Fumonisin B1 (FB1) is one of the most important mycotoxin contaminants of foods, particularly cereals and cereal products, with strict low regulatory levels (of mg/l) in many countries worldwide. An electrochemical competitive aptamer-based biosensor for FB1 is described. The determination of FB1 is essential to minimize the consumption of contaminated foods. Many of the analytical methods for FB1 in foodstuffs have been validated in collaborative studies of the AOAC. These usually use liquid extraction, solid-phase extraction or immunoaffinity columns for the extraction and cleanup of the sample, and high-performance liquid chromatography with fluorescence detection (HPLC– FLD) for determination, obtaining limits of detection below 0.1g kg−1. However, HPLC–FLD methods require sophisticated instrumentation and expertise. Selected aptamers for FB1 were recently described for the first time [1], following characterization by fluorescence polarization and equilibrium dialysis, and were demonstrated to be useful for the determination of FB1 in wheat. The binding affinities of the selected FB1 aptamer, determined by equilibrium dialysis, are in the nanomolar range, comparable to or below the binding constants of antibodies to FB1, and they are very selective to FB1 target molecule, for which they can be used as useful biorecognition elements in biosensors for this mycotoxin. Paramagnetic microparticle beads (MBs) modified with streptavidin were functionalized with an aptamer specific to FB1 and they were allowed to compete with a solution of the mycotoxin. Voltammetric measurements were carried out, connected to three electrode screen-printed carbon electrodes (SPCEs). After separation and washing steps, the modified MBs were localized on disposable screen-printed carbon electrodes (SPCEs) under a magnetic field, and the product of the enzymatic reaction with the substrate was detected with differential-pulse voltammetry (DPV).

Acknowledgments: Science and Innovation Ministry for two new contracts INC10-0178 (INNCORPORA 2010) PTQ-10-03580 (TORRES QUEVEDO 2010), one project IPT-2011-1766-010000 (INNPACTO 2011) and a predoctoral grant AP2010-4609.

Reference [1]

Maureen McKeague, Charlotte R. Bradley, Annalisa De Girolamo, Angelo Visconti , J. David Miller and Maria C. DeRosa, Int. J. Mol. Sci, 11, (2010), 4864-4881.

205


206


Index - Posters

207


208


Only Posters submitted by registered participants are listed below. Last update (16/02/2012) (Please, find your final poster number by looking up your name in the Author Index displayed in the Registration and the Poster Exhibition Areas)

Alphabetical Order (60) Presenting Author Akou

Amal

Alcaraz de Rodrigo la Osa

Country

Topic

Poster Title

Student/ Senior

France

Nanophotonics/NanOptics/ Tunable Diffraction Devices Based On Spin Crossover Materials Plasmonics

Student

Spain

Nanophotonics/NanOptics/ Magneto-optical effects in nano-disks as a perturbation of the optical response Plasmonics

Student

Ali

Lamiaa M. A. Spain

Aranburu Okariz

Nora

Nanotoxicology and Nanosafety

In vitro toxicity studies of polymer coated superparamagnetic iron oxide nanoparticles

Senior

Spain

Nanotubes

Morphology and properties of polyamide 12/mwcnt nanocomposites

Student

Bitri Hamdi Nabila

France

Scanning Probe Microscopies (SPM)

Multiwalled carbon nanotube probes for electrochemistry

Senior

Blasco

Julian

Spain

Nanotoxicology and Nanosafety

Assessing toxicity of citrate-gold nanoparticles at different marine trophic levels (microalgae, Senior copepods and bivalve mollusks)

Bonel

Laura

Spain

NanoBiotechnology / Nanomedicine

Design of a competitive electrochemical biosensor based on affinity reaction between deoxynivalenol and its polyclonal antibody

Senior

Bringas

Eugenio

Spain

NanoBiotechnology / Nanomedicine

Superparamagnetic core-shell nanoparticles: synthesis, characterization and application in targeted drug delivery

Senior

Castillo

Juan Ramon

Spain

Nanotoxicology and Nanosafety

The frontier of the Environmental Analytical Nanotechnology Single Nanoparticle Detection Senior by ICP-Mass Spectrometry Cell Toxicity and Genotoxic Assays

del Corro

Elena

Spain

Nanotubes

Douas

Maysoun

Spain

Compression enhanced conductivity in carbon nanotubes

Senior

Nanophotonics/NanOptics/ Nanoscale optical hydrophilic characterization Student Plasmonics

Echegoyen Yolanda

Spain

Nanotoxicology and Nanosafety

Echevarria Cristina Bonet

Spain

Nanomagnetism

Ezquerra

Spain

NanoBiotechnology / Nanomedicine

Nanostructured biosensor for fumonisin B1 based on paramagnetic beads and a monoclonal antibody

Student

Portugal

NanoBiotechnology / Nanomedicine

Physisorption of Cytochrome c to Nanostructured Gold Surfaces: Relevance for Bionano-Devices and Composites

Senior

Alba

Fernandez InĂŞs Gomes

Migration of nanoparticles from nano-silver food containers

Senior

Field-dependence of the resistivity minimum in Student intermediate valence nanometric YbAl3

209


Presenting Author

210

Country

Topic

Poster Title

Student/ Senior

FernandezJorge Fernado Spain Sanchez

NanoMaterials

Synthesis of a novel polyurethane-basedmagnetic imprinted polymeric nanoparticles for Senior the selective optical detection of 1naphthylamine in drinking water

Fornaguera Cristina

Spain

NanoMaterials

Formation of dexamethasone-loaded nanoparticle dispersions from nano-emulsions Student as inhaled anti-inflammatory drug delivery systems

Franco

Alfredo

Mexico

GallegoGómez

Beatriz

Spain

NanoMaterials

García

Carlos

Spain

Nanotoxicology and Nanosafety

Exposure of the bivalve RUDITAPES PHILIPPINARUM to gold nanoparticles: Location Student study by electron microscopy

García Marín

Antonio

Spain

NanoBiotechnology / Nanomedicine

High-sensitivity ellipsometric immunosensors based on au nanoparticle plasmon resonance in Student al-doped zinc oxide thin films

Garcia Nuñez

Carlos

Spain

NanoMaterials

NanoBiotechnology / Nanomedicine

Photoactive nanoimpellers in sio2 films for controlled drug delivery

Senior

New Generation of Low-Cost/High-Efficiency Solar Photocatalysts for Solar-Driven Energy and Environmental Applications

Senior

Zinc oxide and gallium doped zinc oxide nanowires for optoelectronics Dye-sensitized Solar Cells with enhanced performance using modified ZnO vertically aligned nanorods Synthesis of Upconverting Nanophosphors micelles. A new class of nanoparticles with a potential application for optical biomedical imaging.

Student

GonzalezValls

Irene

Spain

NanoMaterials

Groult

Hugo

Spain

NanoBiotechnology / Nanomedicine

Heinrich

Michael

Germany

Nanotubes

Hermsdörfer Anne

Germany

NanoBiotechnology / Nanomedicine

Horga

Félix

Spain

Nanomagnetism

Izquierdo

Armando

Spain

Other

The Supercontinuum Laser as a Flexible Source for Quasi-Steady State and Time Resolved Senior Fluorescence Studies

Jamier

Vincent

Spain

Other

Centre for NanoBioSafety and Sustainability: “because the world deserves better Nanotechnolgy”

Kangur

Triin

Estonia

Khan

Abid Ali

LagoCachón

David

Student

Student

Process-related mechanical properties of conductive Nanocomposites based on CNTfilled Polypropylen

Senior

Quantitative characterization of biomaterials and their interaction with living cells by AFM

Senior

Magnetic polarization of finite zigzag single walled carbon nanotubes by Fe clusters

Student

Senior

NanoBiotechnology / Nanomedicine

Chemical and topographic effects on fibroblasts Student

Spain

NanoMaterials

Gluing negatively charged Au nanoparticles to Student negatively charged TMV rods

Spain

NanoBiotechnology / Nanomedicine

Specific magnetic cell separation using receptor-mediated endocyted iron oxide nanoparticles

Student


Presenting Author

Country

Topic

Poster Title

Student/ Senior

Impact of process variability and noise on the radiofrequency performance of carbon nanotube field-effect transistors

Student

NanoBiotechnology / Nanomedicine

Electrophoretic deposition to develop new optical sensing materials: application to a wireless oxygen sensing microrobot

Student

Spain

NanoBiotechnology / Nanomedicine

Structuration and improvement of the resistance to culture medium of a modified photocrosslinkable glycosaminoglycan

Senior

Menendez Rosa

Spain

Graphene

Preparation of graphenic materials of different Senior structure

MoralesNarváez

Eden

Spain

Graphene

Optical biosensors based on graphene

Navarro

Enrique

Spain

Nanotoxicology and Nanosafety

Assessing ionic silver availability to algae from Senior differently coated silver nanoparticles

OchoaZapater

María Amparo Spain

Nanotoxicology and Nanosafety

Preliminary results of gold nanoparticles toxicity Student in Blattella germanica

Ortiz

Maria Dolores Spain

Landauer

Gerhard Martin

Spain

Nanotubes

Marín Suárez del Marta Toro

Spain

Márquez

Mª Carmen

Student

Numerical analysis of the plasmonic spectra of

Nanophotonics/NanOptics/ Palladium, Copper, Platinum and Magnesium nanoparticles. New possibilities for UV Plasmonics

Senior

plasmonics

Ortuño

Natalia

Spain

NanoChemistry

Injected bottles based on biopolymers reinforced with modified nanonoclays.

Senior

Peer

Maryam

United States

NanoMaterials

Synthesis and characterization of porous carbon spheres with controlled size

Student

PeñaÁlvarez

Miriam

Spain

Nanotubes

Raman spectra of single walled carbon nanotubes

Student

Pérez López Briza

Spain

Graphene

Graphene for electrochemical biosensing platforms

Senior

Porredon Guarch

Constança

Spain

Nanotoxicology and Nanosafety

Renero Lecuna

Carlos

Spain

NanoMaterials

Rodea Ismael Palomares

Spain

Nanotoxicology and Nanosafety

Rogero

Celia

Spain

NanoChemistry

Intermolecular H-Bonding for Porphyrin Molecules on Surfaces: experimental evidences Senior and theoretical investigation.

Rosal

Roberto

Spain

NanoMaterials

Anti-biofouling efficiency of electrospun polylactic acid membranes doped with silver and copper nanoparticles supported on sepiolite

Ruiz

Carlos

Spain

NanoMaterials

Room Temperature Relative Humidity Sensing Senior using Polypyrrole Conductive Thin-films

Salinas

Beatriz

Spain

NanoChemistry

New methodologies for the functionalization of superparamagnetic nanoparticles; cross olefin Student metathesis

Need for guidelines specifically adapted for the Student toxicity testing of nanomaterials Synthesis and optical properties of Zn1-xCoxO as nanoparticles, thin film and single crystal

Student

Assessment of nanoceria toxicity in aquatic photosynthetic organisms

Senior

Senior

211


Presenting Author

Country

Topic

Poster Title

Student/ Senior

Savateeva Diana

Spain

NanoMaterials

Hybrid organic-inorganic nanostructures combining semiconductor quantum dots and J- Senior aggregates

Sousa

Célia

Portugal

NanoMaterials

Nanoporous alumina template assisted growth Student of nanotubes and nanowires

Vidal

Juan Carlos

Spain

NanoBiotechnology / Nanomedicine

Vílchez

Alejandro

Spain

NanoMaterials

Meso/macroporous dual TiO2 materials, prepared using highly concentrated emulsions Student as templates, and study of its photocatalytic activity

Villalonga Santana

Reynaldo

Spain

NanoChemistry

Decorating carbon nanotubes with polyethyleneglycol-coated magnetic Senior nanoparticles for implementing highly sensitive enzyme biosensors

Spain

Graphene

Magnetic properties of Fe4 cluster adsorbed on Senior a triangular nanographene

Villanueva Pedro

An electrochemical competitive biosensor for fumonisin B1 (FB1) based on a DNA

Senior

Washington

Jasmine

United States

NanoBiotechnology / Nanomedicine

Investigation of Polymer-Functionalized Carbon Senior Nanotubes for Nanomedicine

Zaffino

Rosa Eltizia

Spain

NanoElectronics / Molecular Electronics

DNA’s hybridization detection based on DNA mediated charge transport.

Student

Zamiri

Reza

Malaysia

Laser Assisted Fabrication of ZnO/Ag and ZnO/Au Core/Shell Nanocomposites

Senior

NanoMaterials

212 Poster Contributions by Topics (60) Presenting Author

Country

Poster Title TOPIC: Graphene

Menendez

Rosa

Spain

Preparation of graphenic materials of different structure

MoralesNarváez

Eden

Spain

Optical biosensors based on graphene

Pérez López Briza

Spain

Graphene for electrochemical biosensing platforms

Villanueva

Spain

Magnetic properties of Fe4 cluster adsorbed on a triangular nanographene

Pedro

TOPIC: Nanobiotechnology/Nanomedicine Design of a competitive electrochemical biosensor based on affinity reaction between deoxynivalenol and its polyclonal antibody

Bonel

Laura

Spain

Bringas

Eugenio

Spain

Superparamagnetic core-shell nanoparticles: synthesis, characterization and application in targeted drug delivery

Ezquerra

Alba

Spain

Nanostructured biosensor for fumonisin B1 based on paramagnetic beads and a monoclonal antibody

Fernandez Gomes

Inês

Portugal

Physisorption of Cytochrome c to Nanostructured Gold Surfaces: Relevance for Bionano-Devices and Composites


Presenting Author

Country

Poster Title

Franco

Alfredo

Mexico

Photoactive nanoimpellers in sio2 films for controlled drug delivery

García Marín

Antonio

Spain

High-sensitivity ellipsometric immunosensors based on au nanoparticle plasmon resonance in al-doped zinc oxide thin films

Groult

Hugo

Spain

Synthesis of Upconverting Nanophosphors micelles. A new class of nanoparticles with a potential application for optical biomedical imaging.

Hermsdörfer

Anne

Germany

Quantitative characterization of biomaterials and their interaction with living cells by AFM

Kangur

Triin

Estonia

Chemical and topographic effects on fibroblasts

Lago-Cachón

David

Spain

Specific magnetic cell separation using receptor-mediated endocyted iron oxide nanoparticles

Marín Suárez del Toro Marta

Spain

Electrophoretic deposition to develop new optical sensing materials: application to a wireless oxygen sensing microrobot

Márquez

Mª Carmen Spain

Structuration and improvement of the resistance to culture medium of a modified photocrosslinkable glycosaminoglycan

Vidal

Juan Carlos Spain

An electrochemical competitive biosensor for fumonisin B1 (FB1) based on a DNA

Washington

Jasmine

United States

Investigation of Polymer-Functionalized Carbon Nanotubes for Nanomedicine TOPIC: Nanochemistry

Ortuño

Natalia

Spain

Injected bottles based on biopolymers reinforced with modified nanonoclays.

Rogero

Celia

Spain

Intermolecular H-Bonding for Porphyrin Molecules on Surfaces: experimental evidences and theoretical investigation.

Salinas

Beatriz

Spain

New methodologies for the functionalization of superparamagnetic nanoparticles; cross olefin metathesis

Villalonga Santana

Reynaldo

Spain

Decorating carbon nanotubes with polyethyleneglycol-coated magnetic nanoparticles for implementing highly sensitive enzyme biosensors

TOPIC: NanoElectronics / Molecular Electronics Zaffino

Rosa Eltizia Spain

DNA’s hybridization detection based on DNA mediated charge transport.

TOPIC: Nanofabrication Tools and Nanoscale Integration Mahmud

Syeda Faria Japan

Low energy ion beam fabrication of ultra smooth and sharp AFM nanotips from single crystal diamond rods

Nikulina

Elizaveta

Electron-beam-induced cobalt deposition

Spain

TOPIC: Nanomagnetism Echevarria Bonet Cristina

Spain

Field-dependence of the resistivity minimum in intermediate valence nanometric YbAl3

Horga

Spain

Magnetic polarization of finite zigzag single walled carbon nanotubes by Fe clusters

Félix

213


Presenting Author

Country

Poster Title TOPIC: NanoMaterials

214

FernandezSanchez

Jorge Fernado

Spain

Synthesis of a novel polyurethane-based-magnetic imprinted polymeric nanoparticles for the selective optical detection of 1-naphthylamine in drinking water

Fornaguera

Cristina

Spain

Formation of dexamethasone-loaded nanoparticle dispersions from nanoemulsions as inhaled anti-inflammatory drug delivery systems

Gallego-Gómez

Beatriz

Spain

New Generation of Low-Cost/High-Efficiency Solar Photocatalysts for SolarDriven Energy and Environmental Applications

Garcia Nuñez

Carlos

Spain

Zinc oxide and gallium doped zinc oxide nanowires for optoelectronics

Gonzalez-Valls

Irene

Spain

Dye-sensitized Solar Cells with enhanced performance using modified ZnO vertically aligned nanorods

Khan

Abid Ali

Spain

Gluing negatively charged Au nanoparticles to negatively charged TMV rods

Peer

Maryam

United States

Synthesis and characterization of porous carbon spheres with controlled size

Renero Lecuna

Carlos

Spain

Synthesis and optical properties of Zn1-xCoxO as nanoparticles, thin film and single crystal

Rosal

Roberto

Spain

Anti-biofouling efficiency of electrospun polylactic acid membranes doped with silver and copper nanoparticles supported on sepiolite

Ruiz

Carlos

Spain

Room Temperature Relative Humidity Sensing using Polypyrrole Conductive Thin-films

Savateeva

Diana

Spain

Hybrid organic-inorganic nanostructures combining semiconductor quantum dots and J-aggregates

Sousa

Célia

Portugal

Nanoporous alumina template assisted growth of nanotubes and nanowires

Vílchez

Alejandro

Spain

Meso/macroporous dual TiO2 materials, prepared using highly concentrated emulsions as templates, and study of its photocatalytic activity

Zamiri

Reza

Malaysia

Laser Assisted Fabrication of ZnO/Ag and ZnO/Au Core/Shell Nanocomposites

Akou

Amal

France

Tunable Diffraction Devices Based On Spin Crossover Materials

Alcaraz de la Osa Rodrigo

Spain

Magneto-optical effects in nano-disks as a perturbation of the optical response

Douas

Maysoun

Spain

Nanoscale optical hydrophilic characterization

Ortiz

Maria Dolores

Spain

Numerical analysis of the plasmonic spectra of Palladium, Copper, Platinum and Magnesium nanoparticles. New possibilities for UV plasmonics

Ali

Lamiaa M. A.

Spain

In vitro toxicity studies of polymer coated superparamagnetic iron oxide nanoparticles

Blasco

Julian

Spain

Assessing toxicity of citrate-gold nanoparticles at different marine trophic levels (microalgae, copepods and bivalve mollusks)

Castillo

Juan Ramon Spain

Echegoyen

Yolanda

TOPIC: Nanophotonics/NanOptics/Plasmonics

TOPIC: Nanotoxicology and Nanosafety

Spain

The frontier of the Environmental Analytical Nanotechnology Single Nanoparticle Detection by ICP-Mass Spectrometry Cell Toxicity and Genotoxic Assays Migration of nanoparticles from nano-silver food containers


Presenting Author

Country

Poster Title

García

Carlos

Spain

Exposure of the bivalve RUDITAPES PHILIPPINARUM to gold nanoparticles: Location study by electron microscopy

Navarro

Enrique

Spain

Assessing ionic silver availability to algae from differently coated silver nanoparticles

Ochoa-Zapater

María Amparo

Spain

Preliminary results of gold nanoparticles toxicity in Blattella germanica

Porredon Guarch Constança

Spain

Need for guidelines specifically adapted for the toxicity testing of nanomaterials

Rodea Palomares Ismael

Spain

Assessment of nanoceria toxicity in aquatic photosynthetic organisms TOPIC: Nanotubes

Aranburu Okariz Nora

Spain

Morphology and properties of polyamide 12/mwcnt nanocomposites

del Corro

Elena

Spain

Compression enhanced conductivity in carbon nanotubes

Heinrich

Michael

Germany

Process-related mechanical properties of conductive Nanocomposites based on CNT-filled Polypropylen

Landauer

Gerhard Martin

Spain

Impact of process variability and noise on the radiofrequency performance of carbon nanotube field-effect transistors

Peña-Álvarez

Miriam

Spain

Raman spectra of single walled carbon nanotubes TOPIC: Other

Izquierdo

Armando

Spain

The Supercontinuum Laser as a Flexible Source for Quasi-Steady State and Time Resolved Fluorescence Studies

Jamier

Vincent

Spain

Centre for NanoBioSafety and Sustainability: “because the world deserves better Nanotechnolgy” TOPIC: Scanning Probe Microscopies (SPM)

Bitri Hamdi

Nabila

France

Multiwalled carbon nanotube probes for electrochemistry

215


216

Cover image: HRSEM of the coaxial fibres Credit: Jorge F. Fernรกndez-Sรกnchez (University of Granada, Spain)

Edited by Phantoms Foundation Alfonso Gomez 17 28037 Madrid - Spain info@phantomsnet.net www.phantomsnet.net Deposito legal / Spanish Legal Deposit: BI-401/2012


www.nanospainconf.org

Edited by

Phantoms Foundation Alfonso Gomez 17 28037 Madrid - Spain info@phantomsnet.net www.phantomsnet.net

NanoSpain 2012 Conference  

During the last two decades, a revolutionary scientific new age, based on the capacity to observe, characterize, manipulate and organize mat...

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