Flexible screen printed biosensor with high-Q microwave resonator for rapid and sensitive detection of glucose

This paper presents a rapid and sensitive mediator-free glucose biosensor based on microwave resonator implemented using circularly folded T-shaped uniform impedance resonators, screen printed on flexible polyethylene substrate. As a result of high-Q factor of 160, the proposed glucose biosensor features high sensitivity and ultralow detection limit of 71 MHz/mgmL^-1 and 0.0167 μM, respectively, at a central frequency of 11.8 GHz, within linear detection range of 1 to 5 mg/mL. Additionally, the clear dependence of loaded quality factor (Q_L), return loss (S₁₁), propagation constant (γ), and impedance (Z) on glucose level enables the effective multidimensional detection of glucose sensor.