Enzyme Modification by Immobilization

Enzyme Immobilization Creative Enzymes Inc.

Introduction of Enzyme Immobilization Enzyme Immobilization An immobilized enzyme is an enzyme attached to an inert, insoluble material—such as calcium alginate.

This can provide increased resistance to changes in conditions such as pH or temperature. It also lets enzymes be held in place throughout the reaction, following which they are easily separated from the products and may be used again - a far more efficient process and so is widely used in industry for enzyme catalysed reactions.

History and Commercialization of Immobilized Enzymes

Figure 1. Publication of articles (research and review) on enzyme immobilization (PubMed)

Figure 2. Enzyme-based biosensors: Significance in various sectors as well as their market in various countries across the world.

Methods of Enzyme Immobilization

Figure 3. Overview on the techniques being used for enzyme immobilization.

Physical Method

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Entrapment

Adsorption

Microencapsulation

This involves cross-linking of the enzyme to a polymer in every direction, covering almost every side chain present on the surface of the enzyme by physical entrapment within the polymer lattice. It allows permeation of appropriately sized substrate and release of product molecules, which ensures continuous transformation.

Enzyme is attached to the support material by non-covalent linkages including ionic or hydrophobic interactions, hydrogen bonding, and van der Waals forces without any preactivation of support. Here, the enzyme is directly added to the surface (active adsorbent) without the removal of any non-adsorbed enzyme during washing.

Enzymes are immobilized by enclosing them within spherical semi-permeable polymer membranes with controlled porosity (1–100 μm). Semi-permeable membranes can either be permanent or nonpermanent membranes based on the constituents. These membranes are also used in the encapsulation of dyes, drugs, and other chemicals.

Chemical Method

Covalent Attachment

Cross-Linking

Ionic binding

Conjugation by affinity ligands

The enzyme is attached to the

This involves formation of a

This is based on ionic

Attachment of the enzyme to

matrix by means of covalent

number of covalent bonds

interactions between enzyme

the matrix using specific

bonds. Enzyme molecules are

between enzyme and the

molecules with a charged

ligands; viz, his-tag on

attached either directly to the

matrix using bi- or multi-

matrix. Here, higher the

enzyme to a metal-containing

reactive groups present on the

functional reagents. Generally,

surface charge density on the

matrix, lectin-containing

matrix or by a spacer arm,

amino groups of lysine,

matrix, the greater would be

domain to carbohydrate

which is artificially attached to

sulfhydryl groups of cysteine,

the amount of enzyme being

moieties present on the matrix

the matrix through various

phenolic OH groups of

bound to the matrix. Enzyme

or sometimes substrate-

chemical reactions. Matrices

tyrosine, or imidazol group of

binding via ionic interactions

mimicking chemical

commonly used are either

histidine are used for enzyme

during immobilization depends

compounds are also used as

natural or synthetic.

binding under mild conditions.

on the pH of the solution, the

ligands.

concentration of the enzyme and temperature.

Properties of Immobilized Enzymes

Figure 4. Effects on enzymes being immobilized on various matrices by either method of immobilization.

Enzyme Modification by Immobilization Service

Creative Enzymes Inc.  Quick and rational design  Custom immobilization of enzyme of interest  Available at any scale with short lead times  Variable particle size of immobilized enzyme: 0.05-1mm  High loading rate: > 45%, up to 85%

Enzyme Modification by Immobilization Service

Contact Contact Us Us www.creative-enzymes.com Address: 45-1 Ramsey Road, Shirley, NY 11967, USA

Tel: 1-631-562-8517

Email: info@creative-enzymes.com

Fax: 1-631-938-8127

1-516-512-3133

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