Making field effect transistor measurements accessible to electrochemists and biologists

Field effect transistors (FETs), originally developed in the field of electronic engineering, have gained increasing prominence in biosensing due to their versatile operation characteristics, ranging from recording simple electrical transfer curves to performing chronoamperometric measurements. Commonly known as bioFETs, these devices typically feature low gate voltage operation characteristics, can be made highly selective/sensitive through bioreceptor integration, label-free and do not rely on redox mediators or enzymatic product detection, and are easy to interface with microfluidic or flow cell devices. Despite their advantages, electrochemists and biologists remain still hesitant to explore the possibilities of bioFETs, owing to concerns about investment costs and the complexity of the read-out tools. In this study, we demonstrate the use of a simple, cost-effective bipotentiostat platform, providing an accessible solution for those interested in electronic biosensing without the need to delve into complex electronics. As a proof-of-concept, we showcase the working principle of a graphene-based bioFET for sensing a cardiac biomarker using a peptide nucleic acid (PNA)-aptamer-modified gFET platform. This article focuses on how to easily develop/operate FETs for biosensing measurements using the bipotentiostat-setup and discloses its simplicity over the conventional approaches.