Addressable micropost array for the dielectrophoretic manipulation of particles in fluid

A microfluidic device has been developed to trap and position neutral particles using dielectrophoresis. An array of microscale post shaped electrodes provides an inhomogeneous electric field. The voltage on each electrode can be independently controlled by a computer to trap and move particles in fluid above the micropost electrodes. Yeast cells and polystyrene spheres were trapped and moved, demonstrating both positive and negative dielectrophoresis. (C) 2004 American Institute of Physics.