SMU engineers are working to defeat cancer by shedding light on it. The SMU Photonics Group in the School of Engineering is conducting research on photodynamic therapy (PDT), which destroys cancer cells through the use of red laser light in combination with a photosensitizing drug. The drug, administered to a patient hours before treatment, accumulates mainly in cancerous cells. Illuminating the cancerous area activates the drug and kills the cells, with little damage to surrounding healthy tissue. Assistant Professor of Mechanical Engineering Gemunu Happawana uses semiconductor diode lasers as an optical source – equally powerful as but about 1,000 times smaller than existing PDT lasers, as well as less costly and more efficient. Happawana has developed a self-contained light delivery PDT system that positions semiconductor lasers at the end of a thin coaxial cable, which is inserted into a balloon catheter, allowing precise optical, electrical and thermal control at the tumor’s location. Read more at the SMU Photonics Group Web site.