Particles of interest, such as DNA molecules, are injected into a medium by applying a first field. Once in the medium the particles are concentrated by applying one or more fields that cause mobilities of the particles in the medium to vary in a manner that is correlated with motions of the particles....http://www.google.com.au/patents/US8182666?utm_source=gb-gplus-sharePatent US8182666 - Apparatus and methods for concentrating and separating particles such as molecules
