Patent EP0038181A2 successfully refreshed from Google Patents.
EP0038181A2
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EP
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Agglutination immunoassays
Assignee: Bayer Corp
•
Filing: 1981-04-09
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Granted: —
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Expires: 2001-04-09
Abstract
Abstract In particle agglutination immunoassays for an analyte (e.g. an antigen or antibody) in a liquid sample (eg human serum), interferences arise due to non-specific protein-protein interactions and the like These interferences are reduced or overcome by including in the assay mixture a chaotropic or chaotropic-like agent. in a carefully controlled amount Such agents include guanidine. guanidinium hydrochloride or thiocyanate, sodium or ammonium thiocyanate. and urea, sodium chloride and ethylenediamine tetraccetic acid
Inventors
- 👤 Floris De Steenwinkel
- 👤 Daniel Collet-Cassart
- 👤 Pierre Lucien Masson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 12:17
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54313; Y; Y10; Y10S; Y10S436/00; Y10S436/825
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
105 words
A method of immunoassay for an analyte in a liquid sample, which comprises forming a mixture of the liquid sample with finely divided solid particles bearing a protein coating, the coating constituting or the particle otherwise also bearing a reagent whereby specific agglutination of the particles occurs to an extent dependent on the amount of analyte present, and determining the said extent and thereby the amount of analyte present, characterised in that the mixture also includes one or more chaotropic or chaotropic-like agent is reduce non-specific protein interaction interferences, the amount of said agent(s) being sufficient to reduce the effect on agglutination of said interferences.
Claim 2
Independent Claim
105 words
A method of immunoassay for an analyte in a liquid sample, which comprises forming a mixture of the liquid sample with finely divided solid particles bearing a protein coating, the coating constituting or the particle otherwise also bearing a reagent whereby specific agglutination of the particles occurs to an extent dependent on the amount of analyte present, and determining the said extent and thereby the amount of analyte present, characterised in that the mixture also includes one or more chaotropic or chaotropic-like agent is reduce non-specific protein interaction interferences, the amount of said agent(s) being sufficient to reduce the effect on agglutination of said interferences.
Claim 3
Dependent Claim
23 words
A method according to claim 1, characterised in that the chaotropic agent is guanidinium hydrochloride or thiocyanate, sodium or ammonium thiocyanate, or urea.
Claim 4
Dependent Claim
21 words
A method according to claim 2, characterised in that the chaotropic agent is present in the mixture in the following amounts:
Claim 5
Dependent Claim
37 words
A method according to claim 1, characterised in that the chaotropic-like agent is sodium chloride, EDTA, lithium nitrate, lithium chlorate, lithium isocyanate, lithium bromide, sodium bromide, potassium bromide, potassium thiocyanate, calcium chloride, lithium chloride or lithium iodide.
Claim 6
Independent Claim
23 words
A method according to any preceding claim, characterised in that the mixture also contains a macromolecular substance to enhance the specific agglutination reaction.
Claim 7
Independent Claim
46 words
A method according to any preceding claim, characterised in that the analyte is an antigen or a hapten and wherein the mixture also contains the F(ab') 2 fragments of an immunoglobulin specific to said analyte, but is free from the whole immunoglobulin and F(c) fragments thereof.
Claim 8
Independent Claim
42 words
A method according to any preceding claim, characterisedin that the mixture contains two different particles each bearing a protein coating, the particles differing either in respect of their size or in respect of the reagent they bear, or in both said respects.
Claim 9
Independent Claim
21 words
A method according to any preceding claim, characterised in that the said extent of agglutination is determined by counting unagglutinated particles.
Claim 10
Independent Claim
155 words
A method of immunoassay for an analyte in a liquid sample, which comprises forming a mixture of the liquid sample with finely divided solid particles bearing a protein coating, the coating constituting or the • particle otherwise also bearing a reagent whereby specific agglutination of the particles occurs to an extent dependent on the amount of analyte present, and determining the said extent and thereby the amount of analyte present, characterised in that (a) as a preliminary step, solutions of the same analyte as is under assay are mixed with varying amounts of a chaotropic or chaotropic-like agent and said particles, and the solutions assayed to determine the optimum range of chaotropic agent to reduce non-specific protein interaction interferences whilst retaining the desired immunospecific reaction upon which the assay is based; and then (b) assaying the analyte in the said liquid sample in the presence of said chaotropic agent in an amount within said range.
Claim 11
Independent Claim
155 words
A method of immunoassay for an analyte in a liquid sample, which comprises forming a mixture of the liquid sample with finely divided solid particles bearing a protein coating, the coating constituting or the • particle otherwise also bearing a reagent whereby specific agglutination of the particles occurs to an extent dependent on the amount of analyte present, and determining the said extent and thereby the amount of analyte present, characterised in that (a) as a preliminary step, solutions of the same analyte as is under assay are mixed with varying amounts of a chaotropic or chaotropic-like agent and said particles, and the solutions assayed to determine the optimum range of chaotropic agent to reduce non-specific protein interaction interferences whilst retaining the desired immunospecific reaction upon which the assay is based; and then (b) assaying the analyte in the said liquid sample in the presence of said chaotropic agent in an amount within said range.
Claim 12
Dependent Claim
48 words
A method according to claim 9, characterised in that the chaotropic or chaotropic-like agent is selected from guanidinium hydrochloride or thiocyanate, sodium or ammonium thiocyanate, or urea, lithium nitrate, lithium chlorate, lithium isocyanate, lithium bromide, sodium bromide, potassium bromide, potassium thiocyanate, calcium chloride, lithium chloride and lithium iodide.
References Cited (Backward Citations)
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