Design and Analysis of a Biosensor Transducer with Multifunctions

This study deals with the development of a simple and multifunctional piezoelectric transducer, which can detect two or more species at one time. The transducer for testing consists of an aluminum cantilever beam and a piezoceramic patch. A piezoelectric impedance-based measurement technique is proposed for detecting a very small biospecies mass sensitively. Furthermore, two different types of biomembranes are coated on the beam so that they can detect two kinds of species without causing interference with each other. The problem as to how to determine the optimal positions for coating the membranes are investigated in detail by the finite element method (FEM). The numerical simulations showed a good agreement with the experimental results. Further, a concept for the design of a multifunctional transducer is proposed based on the mode function, and its validation is proved experimentally.