Scientists Fine-Tune Thin Films of DNA with Eye Toward Biomedical Devices

Using DNA from salmon, researchers in South Korea hope to make better biomedical and other photonic devices based on organic thin films. Often used in cancer treatments and health monitoring, thin films have all the capabilities of silicon-based devices with the possible added advantage of being more compatible with living tissue. A thin film is just what it sounds like, a layer of material only nanometers or micrometers thick that can be used to channel light. If the film is a dielectric--that is, an insulator such as glass--it can be used without worrying that it might conduct electricity. "DNA is the most abundant organic material, and it is a transparent dielectric, comparable to silica," said Dr. Kyunghwan "Ken" Oh, of the Photonic Device Physics Laboratory at Yonsei University, Seoul, South Korea. In the November 1, 2017 issue of Optical Materials Express, from The Optical Society (OSA), Dr. Oh and his colleagues lay out their method for fabricating the thin films of DNA in a way that gives them fine control over the material's optical and thermal properties. The open-access article is titled “Cationic Lipid Binding Control in DNA Based Biopolymer and Its Impacts on Optical and Thermo-Optic Properties of Thin Solid Films." As the basis for the silica glass that makes up optical fibers, silicon has long been a dominant material in inorganic photonic devices because it's readily available and easy to work with from the materials perspective. Dr. Oh argues that DNA can play the same role in organic photonic devices because it can be found throughout the living world. It could, for instance, be used to make waveguides similar to silica fibers to carry light within the body.