Fluidic platform with embedded differential capacitively coupled contactless conductivity detector for micro-object sensing

In this paper, we present a microfluidic platform with differential capacitively coupled contactless conductivity detection ((DCD)-D-4) technique for microparticle detection. The microfluidic platform is formed by bonding PDMS channel to glass substrate. The proposed microfluidic sensor embedded in the microchannel consists of three adjacent electrodes. These electrodes are arranged to form differential coplanar capacitor structures to provide high sensitivity. The differential capacitance is changed when a microsized object crosses the sensing area in the microfluidic channel. This microfluidic system with the novel sensing design based on (DCD)-D-4 technique provides a platform for detection the presence of an object as well as its electrical property.