Separation of latex spheres using dielectrophoresis and fluid flow

The authors present a method for separation of two latex spheres populations using dielectrophoresis (DEP) and the fluid drag force. Microelectrodes of a suitable layout are used to trap one population of spheres, while the other one is dragged away from the electrodes by the generated fluid flow. The finite difference method is implemented in C++ to calculate the potential distribution by solving Laplace´s equation. From the potential distribution, the DEP force on particles is calculated. The drag force on particles due to the liquid motion is calculated from the observed fluid velocity. The experimental results are shown to be in good agreement with the numerical solution.