Application of a Complementary Split Ring Resonator Based Biosensor for Detection of Micromolar Glucose Concentrations in Aqueous Solution

This paper presents the application of a complementary split ring resonator (CSRR) based biosensor to determine the concentration of glucose in aqueous solution. Two tightly coupled concentric CSRRs loaded on a patch were realized on a Rogers RT/Duroid 5870 substrate and then a glucose solution was applied on it. The resonant frequency of the bare (without any glucose solution applied) resonator was 5.0 GHz. Change in glucose concentration results in a corresponding change in dielectric properties of the solution. Due to changes in dielectric properties of the surrounding material, the resonant frequency of the resonator shifts. Such a shift can be used to measure the glucose level in the solution. The proposed sensor uses this principle and can sense the glucose concentration in the range of 3 – 7 mg/mL. The resonator has a sensitivity of 1.0 MHz/mgmL
⁻¹
and a simple structure. Thus the sensor has the potential to be used for noninvasive blood glucose level measurement.