Patent ID: 7045342

Claim:
A device for determining the presence in a liquid sample of an analyte wherein liquid sample deposited on a proximal end of the device travels downstream along a liquid path to a distal end of the device, the device comprising: a biphasic substrate comprising (1) a release medium of a first material and, in fluid communication and downstream thereof, (2) a capture medium of a microporous, second, different material, wherein located at the release medium of the biphasic substrate for release therefrom is (i) a labeled conjugate comprising a binding member reactive with a first epitope of the analyte labeled with a detectable marker, and (ii) a capturable component reactive with a second epitope of the analyte, such that if the analyte is present in the sample, the analyte produces a complex comprising the labeled conjugate, the analyte and the capturable component, and located at the capture medium of the biphasic substrate is a capture site for capturing the complex, the capture site having immobilized thereon a capture component having a binding affinity for the capturable component.