Enzymatic selfpowered biosensing devices

Abstract

Self-powered biosensors have been the focus of intense research due to the wide range of potential applications concerning real-time personal healthcare monitoring and disease diagnostics. The increased demand for autonomous biosensors along with the progress achieved in enzymatic fuel cells (EFCs) as power sources, hold great potential for developing new devices. Firstly, focus is given to the concepts underlying the fundamental operation of EFCs, covering both direct electron transfer and mediated electron transfer systems. As an essential step to achieve the required EFC power density performances in real applications, enzyme immobilization is critically discussed in terms of strategies to immobilize and stabilize enzymes at the electrodes of the EFCs. Highlight is then given to the progress obtained in EFCs-based biosensors. Since these devices harvest electrical power from biological systems, their unique advantages favored progress in terms of biomedical applications of self-powered biosensors. Therefore, the most recent advances in implantable, wearable and point-of-care autonomous biosensors incorporating EFCs is summarized and discussed. Key technological challenges are still present, but these devices are on track to achieve the foreseen realization of the full diagnostic potential of enzymatic fuel cells-based biosensors.