Patent ID: 7741106

Claim:
A method for detecting an ionic analyte in a sample in which an analyte is bound to a detection reagent to form a bound complex, comprising the steps of: (A) providing a sensor device comprising: (a) a sample ( 5 ) comprising an ionic analyte and a detection reagent in a conductive fluid, wherein the detection reagent has a net charge different from the analyte; (b) a first permeable polymeric hydrogel plate ( 3 ) and a first spacer plate ( 8 ), which plates provide a compartment for the sample; (c) an anode ( 1 ) juxtaposed to the outside of the first hydrogel plate and not in contact with the sample; (d) a cathode ( 9 ) juxtaposed to the outside of the first spacer plate and not in contact with the sample; (e) a voltage generator ( 10 ) to apply an electric potential to the anode and cathode; and (f) a detector ( 11 ); and (B) adding the ionic analyte and detection reagent in the conductive fluid to the compartment; (C) applying an electrical potential via the voltage generator; and (D) detecting via the detector the bound complex formed from the analyte because the bound complex has a charge that causes it to migrate in a direction opposite from that of the unbound analyte when the electric potential is applied.