Density-dependent particle separation in microchannels using 3D AC-driven electro-osmotic pumps

In this contribution we present a novel mechanism for density-dependent particle separation in microchannels, based on the tunable ratio of viscous drag, inertial and dielectrophoretic forces. The latter are induced by inclined, stepped electrode arrays in the channel, which, driven by AC voltages, enable so-called 3D-AC-electro-osmotic pumping (3D-ACEO). By adjusting the operation parameters of the micropump, particle mixtures can be pumped and separated simultaneously.