A microstrip resonant biosensor for aqueous glucose detection in microfluidic medical applications

A highly sensitive biosensor to detect small variations of glucose concentrations in water is proposed. The sensor structure is based on a planar half-wavelength (lambda/2) microstrip line (MSL) resonator with a microflu-idic container placed on top. The interaction between the electric field and the milliliter range water-glucose solutions under test can be observed measuring the phase shift of the S-parameter from 3.95 to 4.10 GHz. Combining the microwave detection and the microfluidic network, a time efficient and low cost architecture is presented. With this technique, a very sensitive water-glucose concentration of less than 50 mg/dl can be separated.