A continuous size-dependent particle separator using a negative dielectrophoretic virtual pillar array†
Abstract
We present a continuous size-dependent particle separator using a negative dielectrophoretic (DEP) virtual pillar array. Two major problems in the previous size-dependent particle separators include the particle clogging in the mechanical sieving structures and the fixed range of separable particle sizes. The present particle separator uses the virtual pillar array generated by negative DEP force instead of the mechanical pillar array, thus eliminating the clogging problems. It is also possible to adjust the size of separable particles since the size of virtual pillars is a function of a particle diameter, applied voltage, flow rate, etc. At an applied voltage of 500 kHz, 10 Vrms (root mean sqaure voltage) sinusoidal wave and a flow rate of 0.40 μl min−1, we separate 5.7 ± 0.28 μm-, 8.0 ± 0.80 μm-, 10.5 ± 0.75 μm-, and 11.9 ± 0.12 μm-diameter polystyrene (