Self-actuating biosensor using a piezoelectric cantilever and its optimization

This paper presents a self-actuating biosensor based on the piezoelectric cantilever optimized by Taguchi method for the label-free detection of specific biomoleculars. Until now, even though the optimisation of the cantilever-based biosensors have been performed by changing dimensions one by one, few researches have performed the geometric optimisation considering the overall configuration of the piezoelectric cantilever. This paper suggests a method of optimising the piezoelectric cantilever by the Taguchi method. The first resonance frequency, the separation factor, and the sensing signal of the piezoelectric cantilever were selected as the object functions. The resonator driving circuit will keep the cantilever resonance on the binding of the antigen with antibody. By real-time monitoring of the resonance frequency shift by the frequency sensing circuit, the effects of the protein binding on the change of the cantilever stiffness and mass will be investigated.