Particle (both biological and synthetic) separation is important for a wide range of applications in industry, biology, and medicine. In microfluidic devices particles have been separated based on either extrinsic labels (e.g., fluorescence- and magnetic-activated sorting) or intrinsic properties (e.g., size, charge, density, etc.). The latter may take place in a batchwise or continuous-flow process. The batch-process separation typically includes filtration, chromatography, and electrophoresis. In the continuous-flow separation, an external force field (e.g., acoustic, electrical, magnetic, and optical, etc.) acts on particles at an angle to the flow direction and deflects them to different flow paths [1]. Here we introduce a continuous particle separation technique in electrokinetic flow through curved microchannels. This separation results from the cross-stream dielectrophoretic motion induced by channel curvatures [2]. It eliminates the use of in-channel micro-electrodes or micro-obstacles that are required in present dielectrophoresis-based particle separation techniques [3].
Study on Continuous-Flow Particle Separation in a Microchannel using Dielectrophoresis
