A multichannel SPR biosensor with a fixed detection system

Surface plasmon resonance (SPR) sensors with spectral interrogation provide a high refractive index resolution, a large dynamic range and a fixed optical detection module. In this work, we propose a new spectral detection unit that uses only one spectrometer to measure the SPR spectrum from multiple sensing spots rapidly and serially without any mechanical movement. This spectral detection unit is designed based on a spatial light modulator (SLM) configured as a programmable optical aperture for the spectrometer. To demonstrate this concept, a five-channel SPR sensor was built based on the proposed multichannel detection unit and we evaluated the device performance using a refractive index test. The average device refractive index resolution was 1.4 x 10(-6) refractive index units (RIU).