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

Authors：Liu, Xin-Yu; Liang, Jia-Jun^*; Wu, Zhao; Huang, Yan-Hu; Wu, Wei; Feng, Lin-Ping^*; Liang, Yong; Fan, Xiang-Suo

Source：INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, 2021, 31(10): e22845.

DOI：10.1002/mmce.22845

• 3D printing technique
• microwave sensing
• step impedance resonator

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.

• Institution
  广西大学; 玉林师范学院