Improving cancer detection and water safety Dr. Chieu D. Tran, Pfletschinger-Habermann Professor of Chemistry, uses near-infrared multispectral images in his research. Tran’s NIR imaging instrument takes tens of thousands of pictures, each picture at a different wavelength within one millionth of a second. Until 15 years ago, infrared technology was restricted for military reasons, and Tran began working with it as soon as it became available. “It took us a long time to build this field-deployable, rapid-scanning and high-throughput NIR imaging instrument,” Tran says. He also created a special NIR multispectral imaging microscope, which allows him to perform studies and measurements that are impossible with other existing techniques. For one study, he makes a molecule that is one micron in diameter and heats it up in water, shrinking it and making it less water soluble. The technique could be applied to drug delivery, Tran says. For example, researchers could encapsulate a drug in a molecule and heat it up with a laser so that it shrinks, thus expelling and injecting the drug into a cancer cell. Tran’s NIR imaging system could also be used to detect cancer noninvasively and to very quickly detect biological agents and other
Dr. Chieu D. Tran
impurities in water.
Studying the life and death of stars This radio image shows the spiral galaxy M83, one of the systems studied by Dr. Christopher Stockdale, an associate professor of physics who specializes in stellar explosions called supernovae. M83, which has had at least six supernova explosions in the past century, is about 10 to 15 million light years away. “It’s actually relatively close — it’s in the neighborhood,” Stockdale says. The spiral arms extending out in this image are emissions from hydrogen gas, and the bright spots are areas where new stars are forming or where stars have died. Stockdale uses images from the Karl G. Jansky Very Large Array, a radio observatory in New Mexico. Until the observatory’s recent upgrade, researchers could only look at 10 percent of the L Band of the spectrum. “With the new telescope, we can now get up to 10 times the data we could before,” he says. Supernovae that astronomers first saw explode decades ago are still visible in the radio, allowing Stockdale and others to piece together hints of what happened to the stars before they died. “It give us a way to measure star formation,” Stockdale explains. “Then we can learn more about the dynamics of this galaxy.” Dr. Christopher Stockdale
Marquette University
5