Plasmonic Platforms for Biodetection Devices

We designed and experimentally realized the prototype for a bio-recognition device based on Grating Coupled Surface Plasmon Resonance (GCSPR) which can find a wide range of applications for detection of chemical and biological species. A sinusoidal grating (period of 500 nm and peak-to-valley height of 40 nm) was realized by Laser Interference Lithography (LIL) and replicated onto a polymeric resin film. After substrate coating with a Cr/Au film a thio-mPEO (Mw 5000) layer with a medium thickness of 4 nm was deposited onto the plasmonic surface. The SPR detection system allowed to detect the biological layer with a refractive index sensitivity of 995.2°/RIU. Our solution has been demonstrated to be a very sensitive platform for the development of a complete GCSPR biosensor.