Patent ID: 7364921

Claim:
A method of separating at least one target substance from at least one non-target substance in a sample containing a mixture of substances, which comprises: mixing the sample with a quantity of magnetic particles to produce a suspension comprising a magnetic component and a non-magnetic component, wherein the magnetic component comprises magnetic particles bound to the target substance through at least one moiety on the surface of the magnetic particles that directly or indirectly binds to the target substance, and the non-magnetic component comprises the remainder of the sample; placing the suspension onto a substrate material, wherein the substrate material comprises a viscous solution of agar, agarose, methylcellulose, or polyacrylamide that substantially prevents diffusion of the magnetic component unless a magnetic force is applied; exposing the substrate material containing the suspension to a magnetic field of sufficient strength to cause the magnetic component to migrate across the substrate material; and repeatedly applying a pre-determined increase in the magnetic field in a pulsing manner with a frequency sufficient to cause the magnetic component to separate spatially from the non-magnetic component of the suspension.