Introduction of an angle interrogated, MEMS-based, optical waveguide grating system for label-free biosensing

An excellent refractometric sensitivity with a limit of detection towards effective refractive index changes of Δneff < 2 × 10−7 and long-term stability (<10−6 min−1) is reported, as well as the capability to perform affinity measurements for large (>150 kDa) and small (<250 Da) molecules. With fully-integrated optics, electronics and fluidics, the compact, low-power and affordable sensor unit is well-suited for in situ environmental monitoring or point-of-care diagnostics.