DEP-FFF: Field-flow fractionation using non-uniform electric fields

Dielectrophoresis (DEP) - the movement of particles in nonuniform electric fields - can be used in combination with Field Flow Fractionation (FFF) to separate particles with differing dielectric properties. An introduction is given to the technique of DEP-FFF and its application to the separation of cells and other particles. The separation of yeast cells using the subtechniques of steric and hyperlayer DEP-FFF is demonstrated. It is shown that the hyperlayer-DEP-FFF techniques have a number of advantages, including an improved separation efficiency and reduced adhesion to chamber walls. The hyperlayer-DEP-FFF separation technique is also independent of particle size and allows the use of higher medium conductivities than for conventional DEP methods.