Abstract: A dielectrophoretic separation device includes a chamber including an inlet and an outlet disposed between the inlet and the outlet. A plurality of three dimensional electrodes are disposed in within the chamber. The electrodes may take the form of a wire or semi-cylindrical conductors disposed on a substrate. At least some of the electrodes include smooth surfaces so as to create an electric field (in response to an applied alternating current) that has a low strength in a region disposed away from the electrodes and an electric field having a high fields strength in a region between adjacent electrodes. Particulate matter or other species experiencing a positive DEP force may be separated and collected in the gaps or regions formed between adjacent electrodes.