Patent ID: 7091050

Claim:
A method of detecting the presence or level of an analyte in a sample, the method comprising steps of: (a) providing a sample containing an analyte; (b) mixing said sample with a second ligand, which second ligand binds to said analyte when incubated therewith, so that analyte/second ligand complexes are formed; (c) providing a solid phase having bound thereto a first ligand, which first ligand is characterized by an ability to bind to said second ligand in such a way that, were said first ligand and analyte exposed simultaneously to unbound second ligand, said first ligand would compete with said analyte for binding to said second ligand; (d) contacting the mixture produced in step (b) with said solid phase so that unbound second ligand in said mixture binds to said first ligand on said solid phase, said contacting time for a given volume of the mixture in contact with the solid phase at any one time being selected from the group consisting of a time limited to less than about 1 second, 0.48 seconds, 0.16 seconds, and 0.08 seconds; (e) binding a detectable tag to said second ligand either prior to or after step (a), step (b), step (c), or step (d) so that a portion of said tag is retained on said solid phase upon formation of said first ligand/second ligand complex; and (f) detecting said portion of said tag and comparing it to an amount of tag retained on the solid phase in the presence of a known amount of analyte to determine the presence or level of said analyte in said sample.