Selective separation and isolation of particles/cells of similar sizes using dielectrophoresis

A method is proposed for selective separation and isolation of particles/cells of similar sizes based on their different Clausius-Mossotti factors using dielectrophoresis and microfluidics via both calculation and experiment. The device is a straight micro channel (PDMS) with grooves (or cavities) on its ceiling for capturing particles, and electrodes on its bottom wall (glass) for generating electric field. A particle may be carried downstream or pushed into the groove depending on a designed local force balance between dielectrophoretic force, fluid drag and buoyancy. A mixture of polystyrene particles and CL1-5 lung cancer cells can be separated within 10% accuracy. Copyright © (2011) by the Chemical and Biological Microsystems Society.