Fabrication of piezoelectric sensors for biomedical applications

Biosensors are a special class of chemical sensors that take advantage of the high selectivity and sensitivity of biologically active material. We are currently investigating the characteristics of various deposited electrode coatings (Au and Pt) on 10 MHz quartz crystals using the sputtering method. We are also investigating the effect of magnetic behavior (by intermixing Fe and Ni with electrodes) on the binding nature of antigen with the substrate. A change in mass occurs due to the binding of antigens and antibodies on the surface of the thin film coating. The frequency change as a result of a change in mass makes it possible to use these crystals as biological sensor devices. This paper describes the construction of antibody-based piezoelectric crystals capable of detecting mycobacterial antigens in diluted cultures of attenuated PA. tuberculosis. The microstructural features of these crystals have been studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The crystallographic properties have been characterized using the X-ray diffraction (XRD) method. The long term objective of this research is to develop a rapid quantitative method of analysis for the diagnosis of tuberculosis (TB) and other infections caused by mycobacteria, using biosensor technology.