Patent ID: 7300761

Claim:
A method for determining a quantity of an antigen in a biological sample from a subject, comprising exposing the sample to a solid support device having: (a) a first reaction zone which contains a predetermined amount of a first capture antibody bound to the solid support, that binds to a first epitope of the antigen; (b) a second reaction zone which contains a predetermined amount of a second capture antibody bound to the solid support, that binds to a second epitope of the antigen, said first and second reaction zones located so as to be sequentially exposed to the sample; and (c) a reagent zone containing predetermined concentrations of the first and second capture antibodies as incubation antibodies, reactive with the first and second antigen epitopes, and a predetermined concentration of a third antibody bound to a detectable label, said third antibody binding a third epitope of the antigen, wherein the sample is first contacted with the reagent zone of (c) and subsequently either the reaction zones of (a) and (b); wherein the incubation, capture and detection antibodies determine the quantity of the antigen so detected; and wherein a detectable signal in each of the detection zones is directly related to the quantity of antigen so detected.