Non-Invasive Glucose Monitoring Using Wireless Circular Spiral Resonator Sensor

The prevalence of diabetes patients is increasing daily. The necessity for non-invasive continuous glucose monitoring systems arises from the severity of this issue for individuals. This study specifies the design of a non-invasive glucose monitoring sensor employing two symmetrically positioned circular spiral-shaped resonators (CSSRs) on a dielectric substrate. This configuration increases sensitivity to variations in permittivity. The sensor's performance is assessed by simulations on a finger phantom and practical trials with aqueous glucose solutions, confirming its ability to detect glucose concentrations from 0 to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$400 \text{mg} / \text{dL}$</tex>. The experimental findings demonstrate a sensitivity of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$46 \text{KHz} /(\text{mg} / \text{dL})$</tex>, suggesting the sensor's performance for glucose monitoring in diabetic individuals. The dimensions of the sensor are <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$10 \times 10 \times 1.6 ~\text{mm}^{3}$</tex>.