Near-field radio sensing for continuous blood glucose characterization for type 2 diabetic patients

Predominant blood glucose detection techniques are based on finger stick testing with dry taps, finger trauma, pain, and dependency on biochemicals. The prevailing microwave-based approaches lack suitable dielectric contrast sensitivity due to far-field sensing, which displays unreliable characterization of blood glucose concentrations. This study addresses these gaps by developing a near-field sensor for continuous monitoring of blood glucose in interstitial fluid for type 2 diabetic patients. The proposed microwave sensor is based on a dual L-shaped symmetric parasitic element and a complementary rectangular mesh ring resonator. For variations in interstitial fluid permittivity, the former sensor displays a sensitivity of 139 – 605 MHz/RIU and the latter sensor displays a sensitivity of 701 – 748 MHz/RIU for glucose concentrations between 0 mg/dL and 500 mg/dL, respectively. With improved sensitivity, the complementary rectangular mesh ring resonator sensor has been prototyped, demonstrating reliable resonance variation for real-time glucose concentration measurements with stable performance for continuous monitoring in diabetes management.