Microstrip resonator as microfluidic sensor for blood-glucose monitoring

Diabetes Mellitus is a metabolic disorder, which makes high blood glucose level over an extended period. Approximately 1.5 to 5 million deaths were reported every year due to diabetes. In this work, a minimally invasive blood glucose measurement technique using a microstrip split-ring resonator sensor is formulated. This method is based on the shift in resonant frequency of the split-ring resonator with respect to the change in dielectric constant of the surrounding medium. The variation in dielectric constant of blood with change in glucose concentration is the fundamental reason for frequency shift. Microstrip resonator sensors are widely used for determining the dielectric permittivity of solvents. Several configurations of microstrip resonators are used for finding the dielectric constant. A Split Ring Resonator (SRR) model has been fabricated for performance at 2.45 GHz for the dielectric permittivity measurement of glucose-water solutions of various concentrations. This is extended to find glucose level in blood using the same concept. Different blood samples are studied and effective prediction of glucose is possible with this method. The dielectric permittivity is measured using Keysight E 5080 A Vector Network Analyzer.