Myungjae Lee et al., report a Highly Tunable and Fully Biocompatible Silk Nanoplasmonic Optical Sensor. Novel concepts for manipulating plasmonic resonances and the biocompatibility of plasmonic devices offer great potential in versatile applications involving real-time and in vivo monitoring of analytes with high sensitivity in biomedical and biological research.
They report a biocompatible and highly tunable plasmonic bio/chemical sensor consisting of a natural silk protein and a gold nanostructure. Their silk plasmonic absorber sensor (SPAS) takes advantage of the strong local field enhancement in the metal−insulator−metal resonator in which silk protein is used as an insulating spacer and substrate. The silk insulating spacer has hydrogel properties and therefore exhibits a controllable swelling when exposed to water−alcohol mixtures. They experimentally and numerically show that drastic spectral shifts in reflectance minima arise from the changing physical volume and refractive index of the silk spacer during swelling. Furthermore, they apply this SPAS device as a glucose sensor with a very high sensitivity of 1200 nm/RIU (refractive index units) and high relative intensity change.
For more information please visit:
Source: M Lee, H Jeon, S Kim – Nano letters, 2015 – ACS Publications, DOI: 10.1021/acs.nanolett.5b00680
Publication Date (Web): March 30, 2015