Submicron particle trapping using traveling wave dielectrophoresis

The manipulation of the submicron particles suspended in various fluid media using dielectrophoresis in microchannels with interdigitated electrodes had brought recently considerable attention in many scientific areas, both because of their various applications in industry or medicine and because of their harmful effects for human health when inhaled. The dielectrophoresis resulting from an electric field phase gradient is called “traveling wave dielectrophoresis”. This paper analyses the behavior of a submicron particle suspension in a dense and viscous fluid under dielectrophoresis. The manipulation and controlled spatial separation of submicron particle suspensions is performed by a combination of dielectrophoretic (DEP) and traveling wave dielectrophoretic (twDEP) forces. The theoretical background, together with a set of numerical results obtained in the frame of a mathematical model (DEP and twDEP forces, particle trajectories and concentration profiles) in a separation micro system, were presented. The numerical solutions computed by the finite element method give important information for the optimization of the experimental setup.