Designing and integrating microfluidic electrodes for biosensing and micromanipulation

Microfluidic systems enable the precise measurement, manipulation, and control of fluids and particles at the microscale, providing new tools and insights for biological, chemical, and medical research. Electrodes are key components of microfluidic systems, functioning both as sensors for target detection and as microactuators for sample manipulation. The integration of functional electrodes into microfluidic devices has broadened the applications of microfluidic technology across various fields, enhancing its capacity to address complex biochemical challenges. In this review, we first examine the construction of microfluidic electrodes, focusing on manufacturing and bonding methods. We then classify the electrodes into two classes, i.e., sensing and manipulation, and discuss their fundamental principles alongside representative real-world applications. Finally, we highlight current challenges in microfluidic electrode technology and propose innovative design strategies for electrode integration that could stimulate new research into micro/nano fabrication, chemical engineering, and biological engineering.