Dielectrophoretic separation and immunoassay methods on active electronic matrix devices

A method for isolating and detectably labeling at least one bioparticle of interest on an active electronic matrix chip device, wherein the device comprises:

• a substrate, individually addressable electrodes on the substrate, and a permeation layer overlying a plurality of the electrodes on the substrate, further wherein portions of the permeation layer over the electrodes form microlocations of the active electronic matrix chip device, the method comprising:
• a) introducing onto the active electronic matrix device a sample solution containing the bioparticle of interest, wherein the sample solution is of a conductivity suitable for dielectrophoretic isolation of the bioparticle of interest;
• b) passing an alternating current through selected electrodes on the active electronic matrix chip device, wherein the electrodes are selected to produce areas of relatively high alternating current field strength and relatively low alternating current field strength at positions on the active electronic matrix chip device, wherein the alternating current is supplied at a suitable voltage and frequency for dielectrophoretic isolation of the bioparticle of interest, and further wherein one or more positions of alternating current field strength at which the bioparticle of interest is predicted to aggregate are at one or more aggregate microlocations of the active electronic matrix chip device;
• c) maintaining the alternating current in (b) for a sufficient length of time to allow the bioparticle of interest to aggregate at the aggregate microlocations;
• d) introducing onto the active electronic matrix chip device a solution comprising a detection immunoreagent specific for the bioparticle of interest;
• e) passing a direct current through one or more aggregate microlocations, wherein the electrodes under the aggregate microlocations are biased so as to attract the detection immunoreagent to the aggregate microlocations from the solution;
• and
• f) maintaining the direct current in (e) for a sufficient time to allow the detection immunoreagent to bind to the bioparticle of interest at the aggregate microlocation, thereby detectably labeling the bioparticle.