High-Q silk fibroin whispering gallery microresonator
  We have experimentally demonstrated an on-chip all-silk fibroin whispering gallery mode microresonator by using a simple molding and solution-casting technique. The quality factors of the fabricated silk protein microresonators are up to 10^5. A high-sensitivity thermal sensor was realized in this silk fibroin microtoroid with sensitivity of 1.17 nm/K, 8 times higher than previous WGM resonator based thermal sensors. This opens the way to fabricate biodegradable and biocompatible protein based microresonators on a flexible chip for biophotonics applications. 
Linhua Xu, Xuefeng Jiang, Guangming Zhao, Ding Ma, Hu Tao, Zhiwen Liu,   Fiorenzo G. Omenetto, Lan Yang
physics.optics