Effective and low-cost fluid concentration sensing biosensor based on step-impedance resonators

This article presents a cost-effective step impedance resonator (SIR) for fluid concentration sensing. The sensing mechanism is based on the frequency resonant zero shifting by loading dielectrics with different electrical permittivity. The proposed biosensor mainly consists of two parts: a pair of SIRs and a microfluidic channel. The SIRs are fabricated on a PCB substrate feeding by straight microstrip lines. The microfluidic channel is made by a 3D printing technique. The microfluidic channel is loaded across the surface of the SIRs. The transmission frequency resonant zero is distinguishable by filling different concentrations of liquid. Electromagnetic numerical simulation is performed to verify the theoretical expectation, and glucose standard solution with different concentrations is finally used to demonstrate the feasibility of the proposed biosensor.

Automated summary

This article presents a cost-effective method for fluid concentration sensing using a step impedance resonator (SIR) and loading dielectrics to shift the frequency resonant zero. The proposed biosensor consists of SIRs and a microfluidic channel, with electromagnetic numerical simulation verifying the theory and testing glucose solutions of different concentrations to demonstrate feasibility.