Patent ID: 8257568

Claim:
A method for concentrating and separating particles in water, comprising the steps of: providing an ultrafiltration (UF) module comprising a fluid inlet port, a filter means, wherein the filter means comprises a filter media having a molecular weight cut-off (MWCO) smaller than an average mean diameter of a particle of interest, a retention volume wherein a volume of water comprising particles whose average mean diameter is greater than the MWCO are retained and concentrated, a filtrate discharge port, and a retention discharge port; providing a first substrate comprising a first plurality of fluid flow channels disposed therein comprising a fluid inlet in fluid communication with a fluid outlet, electrodes in electric communication with the fluid inlet and fluid outlet, and a plurality of insulating structures disposed therein; providing manifold means disposed between and in fluid communication with the UF retention discharge outlet and the inlets of each of the plurality of fluid flow channels; providing a water sample comprising a plurality of particles suspended therein; passing the water sample through the fluid inlet port and into the UF module; collecting a portion of the water sample within the retention volume in which particles larger than the UF filter MWCO to provide thereby a concentrated particle suspension; passing the concentrated particle suspension through the manifold means and into the fluid inlets of the plurality fluid flow channels; applying an electric field to the particle suspension to effect dielectrophoretic separation and trapping of the suspended particles; and extracting the trapped particles from each of the plurality of fluid flow channels.