Patent ID: 7211181

Claim:
A method for separating molecules, comprising applying a voltage to a photo-sensitive electrode and a counter electrode to generate a depletion region on the photo-sensitive electrode, wherein the electrodes are separated by an electrolyte medium in contact with the photo-sensitive electrode, wherein the electrolyte medium comprises a plurality of analytes; contacting the depletion region with a photon energy source, wherein the photon energy source generates photon energy such that photon energy contacting the depletion region forms electron-hole pairs that are separated by the potential to form a photopotential; and continually changing the location of contact of the photon energy with the depletion region parallel to the photo-sensitive electrode such that a photopotential is propagated across the photo-sensitive electrode and proximal to the location of the analytes thereby causing the analytes to migrate relative to the photopotential.