Glucose Minimal Concentration Limit Determination Using Waveguide-Differential Dielectrometer at Microwaves

Minimal glucose concentration limit in water solution using dielectrometry method was determined at microwave frequency. The complex permittivity of water-glucose solutions measurements were carried out using a designed waveguide-differential dielectrometer. It allows us the real-time determination of the pharmaceutical ingredients existence in water solution by measuring the wave phase and amplitudes differences in a dielectrometer differential measurement cavity. Minimal glucose concentration limits in water solution are 0.28% and 0.059% have been obtained using the values of measured phase and amplitude differences, respectively. Using these values we have obtained the minimum concentration limit of glucose in the water solution as 1.5 and 0.33 mmol/l, respectively. These results can be compared with known high-cost methods. The waveguide-differential dielectrometer can be applied for the determination of the complex permittivity of any water solutions, for example, water-glucose solutions at microwaves that allow us to find out physical parameters of the liquid under test.