Design and Fabrication of Vertical Electrodes in Microchannels for Particles/cells Sorting by Dielectrophoresis

We have developed a process to fabricate vertical electrodes in the side walls of the microchannel. With appropriate electrodes design, DEP force along the lateral direction of the channel can be generated so that one can position particulates along the width dimension of the channel. The effect of different electrode configurations on the efficacy of generating non-uniform electric field distribution has been studied by FEM Simulation with CFD-ACE. Electrodes with various length ratios and interdigited electrodes have been designed and studied on the generation of non-uniformity of the electric field. Compared to electrodes with different length ratios, side-wall interdigited electrodes provide more consistent direction of DEP force. Experiments on the manipulation of polystyrene microbeads and HEK293 cells with DEP have been demonstrated to verify the performance of the design. The particles/cells can be focused in the middle of the channel, trapped on the side walls, and sorted to different outlets by the flow.