Silk Optics: Biodegradable and Biocompatible Optics

Photo courtesy of iStockphoto, Tor Lindqvist Biomedical engineers from Tuft's University have developed a novel silk-based optics that may be used in devices such as sensors which would combine sophisticated nanoscale optics with biological readout functions. In addition, silk optics offer further advantages in that they are biocompatible and biodegradable, and can be manufactured and stored at room temperatures without use of toxic chemicals. To form the devices, Tufts scientists boiled cocoons of the Bombyx mori silkworm in a water solution and extracted the glue-like sericin proteins. The purified silk protein solution was ultimately poured onto negative molds of ruled and holographic diffraction gratings with spacing as fine as 3600 grooves/mm. The cast silk solution was air dried to create solid fibroin silk films that were cured in water, dried and optically evaluated. A similar process was followed to create lenses, microlens arrays and holograms. Film thicknesses...