Brain cell activity detection using optical grating-based surface plasmonic resonance sensor

Optical neural recordings are label-free and non-toxic as compared to the other methods. We introduce a compact and reliable membrane activity detection sensor based on surface plasmon resonance (SPR) and optical grating. We utilized a fiber optic port to direct light to the optical grating, allowing us to avoid bulky optical setups. Commercial DVD serves as the optical grating, which is both cost-effective and of high quality. In this sensor, we place mouse hippocampal tissue on the Au-sputtered gratings, and by measuring the reflectance spectrum, we investigate the SPR wavelength shift. The introduction of a high-K + aCSF solution allows us to easily observe the effect of cell depolarization on the SPR wavelength can easily be observed. The proposed sensor achieves a high sensitivity of 628.06 nm/RIU.