Patent ID: 7629178

Claim:
An immunoassay test device, comprising: a test strip comprising: a porous sample receiving member configured to receive a liquid sample, a macroporous body, a porous nitrocellulose strip comprising a detection zone, an analyte or an analogue thereof immobilized in the detection zone, and a labeled reagent comprising a particulate label portion and a first binding reagent capable of binding the analyte or the analogue thereof, the particulate label comprising a colored particle, the labeled reagent is disposed in the macroporous body in a dry state and is mobilizable by the liquid sample that passes along a flow path, and the labeled binding reagent is configured to competitively form a complex with analyte present in the liquid sample or with the analyte or the analogue thereof immobilized in the detection zone, wherein, the test strip defines the flow path along which the liquid sample received by the sample receiving member can pass to the macroporous body and thereafter to the porous strip and formation of an immobilized complex in the detection zone is indicative of the absence of the analyte in the liquid sample.