Abstract
Direct current dielectrophoretic (DC-DEP) effects on the electrophoretic motion of charged polystyrene particles through an L-shaped microchannel were experimentally and numerically studied. In addition to the electrostatic and hydrodynamic forces, particles experience a negative DC-DEP force arising from the interaction between the dielectric particle and the induced spatially non-uniform electric field occurring around the corner of the L-shape microchannel. The latter force causes a cross-stream DEP motion so that the particle trajectory is shifted towards the outer corner of the turn. A two-dimensional (2D) Lagrangian particle tracking model taking into account the induced DC-DEP effect was used to predict the particle trajectory shift through the L-shaped channel, which achieves quantitative agreement with the experimental data.