Chapter 4: Rapid Detection of Microorganisms Based on FET Devices

Field-effect transistors (FETs) have surpassed the existing standards of medical sensing technologies in terms of sensitivity, response time, ease of use, low production cost, and availability. The integration of customized bio-recognition elements such as enzymes, antibodies, aptamers, ion-selective membranes, and so on into the device makes it highly selective. The incorporation of nanotechnology improves the performance of FET-based biosensors dramatically, notably the use of nanomaterials such as graphene, single- and multi-walled carbon nanotubes, nanowires, MoS₂, WSe₂, and others. Furthermore, their commercial availability and large-scale high-quality manufacture make them one of the most prominent sensing and screening platforms. This chapter introduced the basic principles of FET-based biosensor devices and their characterization parameters. The chapter further provides a qualitative idea on the techniques and development of various pathogen biosensor-based FETs.