Recent Progress in Rapid Biosensor Fabrication Methods: Focus on Electrical Potential Application

The coronavirus disease pandemic has led to an urgent need for rapid and accurate viral diagnosis. Therefore, rapid biosensors, not only for viruses but also for the detection of bacteria, disease diagnosis, and environmental monitoring, have been actively researched. Biosensors analyze the binding of biomolecules and target substances mainly based on electrochemical, electrical, or optical methods. To achieve precise and rapid diagnosis, it is crucial to reduce the time required for biomolecule–target substance binding. Typically, biomolecules reach the target substances through random diffusion, and to overcome the limitations associated herewith, biosensors have been integrated with alternating current (AC) electrokinetics (ACEK) technology. ACEK, through the application of alternating voltages, converts electrical energy into fluid motion, inducing pumping, mixing, concentration, and separation of the fluid. Its low power consumption makes it highly promising as a point-of-care diagnostic device. In this paper, we review the advancements in three ACEK technologies: AC electrothermal flow, AC electro-osmosis, and AC di-electrophoresis, to discuss the development of rapid biosensor fabrication methods based on electrical potential applications.