Quantifying continuous-flow dielectrophoretic trapping of cells and micro-particles on micro-electrode array

An interdigitated electrode array embedded within a micro-channel with forced flow is shown to enable dielectrophoretic (DEP) characterization of particles and/or cells based on measurements of their trapping percentage over a continuous frequency range. A simplified model of the trapping percentage, using spatial averaging of the convective and DEP force, linearly correlated it to the effective DEP force (in its positive mode). Thus, the Clausius–Mossotti factor was fitted to the experimental data, yielding effective electrical characteristics of the particles and/or cells. Also, the generated trapping percentage curve response over a continuous range of frequencies facilitates sorting and detection based on differences other than just the cross-over frequencies.