An In-Vitro Study of Wireless Passive Inductor Integrated Cavity for Future long-term Implantable resonator-based Glucose Monitoring

In this paper, a label-free biosensor is developed for monitoring the glucose level in the solution. A wireless passive inductor integrated cavity (IIC)-based biosensor is studied. The proposed IIC consists of a passive spiral inductor integrated cavity resonator for continuous monitoring of capillary blood glucose. The proposed method is based on the cavity perturbation theory, where the solution with different glucose levels perturbs and interacts with the passive IIC-based biosensor. The variation in the effective permittivity ε_eff and permeability μ_eff of the cavity resonator due to different glucose levels changes the equivalent capacitance and inductance of the proposed IIC. In turn, the corresponding resonance frequency changes. The in-vitro measurements are performed on deionized water glucose solutions of various glucose concentrations within the range of 75 mg/dL to 250 mg/dL. The results demonstrate that the sensor's resonant frequency increases with the increase in glucose level in the solution with a sensitivity of 32 kHz/mgdL^-1.