Sandwich immunoassay

Claim 2

An immunoassay method for determining the amount of a polyvalent ligand in a liquid test sample, the ligand being a binding substance or a substance capable of specific binding to a binding substance, the method comprising the steps of: (a) providing an insoluble phase to which is bound a separation specific binding substance which does not bind the ligand; (b) incubating the insoluble phase with (1) the liquid test sample; (2) a capture specific binding substance which specifically binds the ligand, and which is itself specifically bound by the separation specific binding substance; and (3) a probe specific binding substance which specifically binds the ligand at a site which is accessible when the ligand is bound to the capture specific binding substance, the probe specific binding substance being not substantially bound by the separation specific binding substance, and being detectable by at least one detection procedure; (c) separating the insoluble phase, after the incubation, from resultant liquid phase containing unbound reagents and components of the test sample; and (d) determining, by means of the detection procedure, the amount of the detectable probe which is bound to the separated insoluble phase, or the amount of the detectable probe remaining in the resultant liquid phase, the determination being related to the amount of the ligand in the test sample.

Claim 3

An immunoassay method for determining the amount of each of a plurality of polyvalent ligands in a liquid test sample, each of the ligands being a binding substance or a substance capable of specific binding to a binding substance, the method comprising the steps of; (a) providing an insoluble phase to which is bound at least one separation specific binding substance which does not bind any of the ligands; (b) incubating the insoluble phase with (1) the liquid test sample; (2) for each of the ligands a capture specific binding substance which specifically binds that ligand, and which is itself specifically bound by the separation specific binding substance; and (3) for each of the ligands, a probe specific binding substance which specifically binds that ligand at a site which is accessible when the ligand is bound to the capture specific binding substance, each of the probe specific binding substances being not substantially bound by the separation specific binding substance, and each being separately detecthle by at least one detection procedure; (c) separating the insoluble phase, after the incubation, from the resultant liquid phase containing unbound reagens and components of the test sample; and (d) determining, by means of the detection procedure, the amount.of each of the detectable probes which is bound to the separated insoluble phase, or the amount of the detectable probe remaining in the resultant liquid phase, the determination being related to the amount of the ligand in the test sample.

Claim 4

An immunoassay method for determining the amount of each of a plurality of polyvalent ligands in a liquid test sample, each of the ligands being a binding substance or a substance capable of specific binding to a binding substance, the method comprising the steps of; (a) providing an insoluble phase to which is bound at least one separation specific binding substance which does not bind any of the ligands; (b) incubating the insoluble phase with (1) the liquid test sample; (2) for each of the ligands a capture specific binding substance which specifically binds that ligand, and which is itself specifically bound by the separation specific binding substance; and (3) for each of the ligands, a probe specific binding substance which specifically binds that ligand at a site which is accessible when the ligand is bound to the capture specific binding substance, each of the probe specific binding substances being not substantially bound by the separation specific binding substance, and each being separately detecthle by at least one detection procedure; (c) separating the insoluble phase, after the incubation, from the resultant liquid phase containing unbound reagens and components of the test sample; and (d) determining, by means of the detection procedure, the amount.of each of the detectable probes which is bound to the separated insoluble phase, or the amount of the detectable probe remaining in the resultant liquid phase, the determination being related to the amount of the ligand in the test sample.

Claim 5

A method as claimed in Claim 1 or 2, wherein the ligand (or each of them) is an antibody, and the capture specific binding substance (or each of them) comprises a specific binding complement to the antibody.

Claim 6

A method as claimed in Claim 1, 2 or 3, wherein each of the probe specific binding substance and the capture specific binding substance (or each of them) comprises an antibody, and the ligand (or each of them) is a specific binding complement to both of the antibodies.

Claim 7

A method as claimed in Claim 1, wherein the capture specific binding substance (or each of them) is conjugated to a hapten, and the separation specific binding substance is an antibody which specifically binds the hapten.

Claim 8

An immunoassay kit, suitable for determining the amount of a polyvalent ligand in a liquid test sample, the kit comprising: (a) an insoluble phase to which is bound a separation specific binding substance which does not bind the ligand; (b) a capture specific binding substance which specifically binds the ligand, and which is itself capable of being specifically bound by the separation specific binding substance; and (c) a probe specific binding substance which specifically binds the ligand at a site which is accessible when the ligand is bound to the capture specific binding substance, the probe specific binding substance being not substantially bound by the separation specific binding substance, and being detectable by at least one detection procedure.

Claim 9

An immunoassay kit, suitable for determining the amount of a polyvalent ligand in a liquid test sample, the kit comprising: (a) an insoluble phase to which is bound a separation specific binding substance which does not bind the ligand; (b) a capture specific binding substance which specifically binds the ligand, and which is itself capable of being specifically bound by the separation specific binding substance; and (c) a probe specific binding substance which specifically binds the ligand at a site which is accessible when the ligand is bound to the capture specific binding substance, the probe specific binding substance being not substantially bound by the separation specific binding substance, and being detectable by at least one detection procedure.

Claim 10

An immunoassay kit, suitable for determining the amount of each of a plurality of polyvalent ligands in a liquid test sample, each of the ligands being a binding substance or a substance capable of specific binding to a binding substance, the kit comprising; (a) an insoluble phase to which is bound at least one separation specific binding substance which does not bind any of the ligands; (b) for each ligand, a capture specific binding substance which specifically binds that ligand, and which is itself specifically bound by the separation- specific binding substance; and (c) for each ligand, a probe specific binding substance which specifically binds that ligand at a site which is accessible when the ligand is bound to the capture specific binding substance, each probe specific binding substance being not substantially bound by the separation specific binding substance, and each being separately detectable by at least one detection procedure.

Claim 11

An immunoassay kit, suitable for determining the amount of each of a plurality of polyvalent ligands in a liquid test sample, each of the ligands being a binding substance or a substance capable of specific binding to a binding substance, the kit comprising; (a) an insoluble phase to which is bound at least one separation specific binding substance which does not bind any of the ligands; (b) for each ligand, a capture specific binding substance which specifically binds that ligand, and which is itself specifically bound by the separation- specific binding substance; and (c) for each ligand, a probe specific binding substance which specifically binds that ligand at a site which is accessible when the ligand is bound to the capture specific binding substance, each probe specific binding substance being not substantially bound by the separation specific binding substance, and each being separately detectable by at least one detection procedure.

Claim 12

A kit as claimed in Claim 6 or 7, the kit being suitable for use wherein the ligand (or each of them) is an antibody and wherein the capture specific binding substance (or each of them) comprises an antigen which is a specific binding complement to the antibody.

Claim 13

A kit as claimed in Claim 7, suitable for the simultaneous determination of CEA and CSAp, wherein one of the capture specific binding substances and one of the probe specific binding substances is a monoclonal antibody which specifically binds CEA, and one of the capture specific binding substances and one of the probe specific binding substances is a monoclonal antibody which specifically binds CSAp.

Claim 14

A kit as claimed in Claim 7, wherein each of the capture antibodies is conjugated to a carborane moiety; and wherein the separation specific binding substance comprises an antibody which specifically binds the carborane moiety.