Design of Electrochemical Microfluidic Detectors: Accurate Potential Measurement.

Potential drop due to the electrolyte conductivity between the reference electrode (RE) and the working electrode leads to measurement error. Because of the limited amount of electrolyte and constricted geometry in microfluidic systems, the total potential drop in a microfluidic system is confined within a small part of the cell. This makes the choice and placement of the RE an important consideration. In this article, we discuss ways to incorporate an RE in a microfluidic system and, through numerical modeling and experimental verification, present some design strategies for electrode placement to ensure accurate potential control.