Design and Fabrication of Acoustic Wave Biosensor for the Detection of Cardiac TroponinI in Serum

In this study, the aim is to develop a high-sensitivity acoustic wave biosensor with a low detectable mass for the identification of cardiac troponin I. Love sensors, a type of surface acoustic wave (SAW) sensor, are designed in this research for the measurement of troponin I. A Love sensor consists of a transducer region and a sensor region. The transducer region is made up of interdigitated transducers (IDTs), which are metal electrodes positioned between the piezoelectric substrate and the conductive layer. The input is electrically excited by applying a radio frequency signal, which generates a mechanical acoustic wave that propagates through the piezoelectric material and is directed towards the IDT output through the conductive layer, where it is converted into a measurable electrical signal. The sensor region is the surface area between the input and output IDTs, where the analyte is exposed. Aluminum electrodes are deposited onto a ZnO substrate, and the CTNI aptamer is immobilized in the sensor region through specific steps. The binding of CTNI in the sample to the aptamer induces a mass change, which causes a shift in the amplitude of the acoustic wave at the output IDT relative to the input IDT. The response will be analyzed using an oscilloscope.