Resonant-based microwave biosensor for physiological liquid identification

This publication deals with a capacitive RF-based resonant biosensor applied to physiological solutions identification. The first two resonances of the structure correspond to 5.83 GHz and 18.72 GHz respectively. They have been considered to investigate the sensitivity of the biosensor regarding sodium-chloride and glucose content in aqueous solution. Transmission contrasts (with respect to pure water) of 0.4 and 0.1 dB at the resonant-frequencies have been achieved for 7 mg/ml of salt and 10 mg/ml of glucose respectively. Beyond the fact that such an approach is able to sense glucose content in physiological liquid, which is rich in ionic content, such multi-frequency analysis opens the route to multi-components analysis of biological and physiological aqueous solutions.