A new rectangular dielectric resonator sensor for glucose measurement: Design, modeling, and experimental validation

This study introduces a novel sensor for glucose measurement based on a rectangular dielectric resonator (RDR) excited by a rectangular slot fed by a 50-Ω microstrip line. The RDR operates at 6 GHz and incorporates a cubic portion section for accommodating a finger or container containing the test sample. By utilizing the distinctive resonant frequencies associated with varying dielectric permittivity of different glucose concentrations, the proposed RDR functions as a reliable sensor. The sensor's performance is evaluated through a 3D electromagnetic model of the human thumb and the application of the Cole-Cole method for modeling the blood layer. Experimental validation is conducted using three alternatives (water, glucose, and alcohol) and a range of glucose concentrations (70 to 2000 mg/dL) in simulation. During experimental verification, an invasive glucometer is employed as a reference for blood sugar levels. Results demonstrate that the proposed RDR sensor exhibits higher sensitivity (36.86 MHz/(mg/dL)) than other sensor counterparts. The experimental outcomes confirm the resonance frequency alignment between the manufactured sensor and the simulated projections. Considering its economic viability and applicability, this sensor represents a promising alternative biosensor for monitoring blood glucose levels.