Microwave and Impedance Spectroscopy as a Useful Tool for Testing Dielectric Properties of Glucose Solutions

Diabetes is one of the most common social disease in the world. Due to the patient discomfort associated with sample collection using a commercially available devices, there is a great need to design a more favorable and precise sensor of blood glucose level. Promising techniques are based on the correlation between glucose-induced variations and blood dielectric properties. This report presents two possible methods showing the variations of impedance modulus and relative permittivity values in glucose-sodium chloride (0.9%) and glucose-bovine plasma solutions at different concentrations, ranging from 50 to 500 mg/dl, occurring in human blood. It is worth noticing, that in each sample the dielectric properties depend on the glucose concentration of the sample over the whole studied range, that is 1 kHz-2 MHz for impedance measurements and 100 MHz-5.5 GHz for microwave spectroscopy. The experimental results as well as discussion of the results, are presented in this paper.