Electrical quantitative assessment of dielectrophoretic focusing in a microchannel

This paper reports a system for the quantitative assessment of dielectrophoretic (DEP) focusing of particles flowing in a microfluidic impedance cytometer. The cytometer performs an electrical measurement of particle trajectories lateral positions before and after a DEP focusing region. Lateral positions are measured using a non-standard electrode configuration yielding an asymmetric bipolar Gaussian signal. The peak amplitude relative difference ? of the signal (introduced in previous work to compensate for positional dependence effects) correlates with particle position. The system was validated by analyzing the focusing of polystyrene beads for different DEP field intensities, obtaining different degrees of focusing. Copyright ? (2018) by Chemical and Biological Microsystems Society. All rights reserved.