Anti-resonance Suppression on A Quartz Crystal Microbalance Sensor for Biosensing Applications

The existence of shunt capacitance in Quartz Crystal Microbalance (QCM) structure leads appearance of anti-resonance in the spectral response. The anti-resonance leads to higher impedance than the mechanical resonance, affecting the primary frequency resonant determination. In this work, a reference spectral subtraction method was applied to remove the effect of passive capacitance on the resonance spectra of a QCM sensor. Principally, a reference spectral was subtracted from the sensor spectral using a particular calculation, resulting in optimized/compensated spectral responses. Furthermore, an antibody layer could be immobilized on the employed QCM to detect protein or virus agents. A propitious resonance shifting of 6.4 kHz was obtained by immobilizing the antibody layer on the QCM sensor. Hence, it leads to an excellent potency to further develop QCM-based biosensors.