Patent EP0420170A2 successfully refreshed from Google Patents.
EP0420170A2
Expired / Lapsed
EP
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Stabilizing reagent for membrane immunoassay
Assignee: Becton Dickinson and Co
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Filing: 1990-09-26
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Granted: —
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Expires: 2010-09-26
Abstract
Abstract A method for immunoassay for a ligand is performed on a porous membrane wherein the signal detected is development of a color on the membrane. The color of the signal and background is substantially stopped and stabilized for reading of the assay at a later time by passing a color stabilizing reagent which includes an acid through the membrane.
Inventors
- 👤 Randal A. Hoke
- 👤 Colleen M. Nycz
- 👤 Jillian A. Robson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 10:12
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/569; G01N33/56983; G01N33/58; G01N33/581
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
145 words
A method for determining a ligand in a liquid comprising: a) combining a first liquid suspected of containing a ligand with a porous membrane coated with an inert protein and with a tracer including a hydrolase whereby said ligand attaches to the coated membrane and to said tracer to give a bound fraction including said enzyme on said membrane; b) separating said membrane from said first liquid by causing said first liquid to pass through said membrane; c) passing a second liquid containing a substrate for said hydrolase comprising a tetrazolium salt and an indoxyl derivative through said membrane, said substrate being converted by said hydrolase on said membrane to a colored product; d) directing a color stabilizing reagent comprising an acid through said membrane; and e) determining the presence of said ligand in said first liquid by detecting said colored product on said membrane.
Claim 2
Independent Claim
145 words
A method for determining a ligand in a liquid comprising: a) combining a first liquid suspected of containing a ligand with a porous membrane coated with an inert protein and with a tracer including a hydrolase whereby said ligand attaches to the coated membrane and to said tracer to give a bound fraction including said enzyme on said membrane; b) separating said membrane from said first liquid by causing said first liquid to pass through said membrane; c) passing a second liquid containing a substrate for said hydrolase comprising a tetrazolium salt and an indoxyl derivative through said membrane, said substrate being converted by said hydrolase on said membrane to a colored product; d) directing a color stabilizing reagent comprising an acid through said membrane; and e) determining the presence of said ligand in said first liquid by detecting said colored product on said membrane.
Claim 3
Dependent Claim
28 words
The method of Claim 2 wherein said ligand is a viral antigen selected from the group consisting of Herpes simplex virus, Respiratory syncytial virus and Influenza A virus.
Claim 4
Dependent Claim
36 words
The method of Claim 1 wherein said tracer further comprises an antiligand specific for said ligand having said hydrolase conjugated thereto, said hydrolase being selected from the group consisting of a peptidase, esterase, phosphatase and glycosidase.
Claim 5
Dependent Claim
22 words
The method of Claim 1 wherein said acid is selected from the group consisting of a mineral acid and an organic acid.
Claim 6
Dependent Claim
13 words
The method of Claim 1 wherein said reagent further comprises an organic solvent.
Claim 7
Independent Claim
147 words
A method for determining a viral antigen in a liquid comprising: a) combining a first liquid suspected of containing a viral antigen with a membrane coated with an inert protein and with an antibody specific for said antigen having alkaline phosphatase conjugated thereto whereby said viral antigen attaches to said coated membrane and to said antibody to give a bound fraction including said alkaline phosphatase on said membrane; b) separating said membrane from said first liquid by causing said first liquid to pass through said membrane; c) passing a second liquid containing indoxyl phosphate and nitroblue tetrazolium through said membrane, said alkaline phosphatase converting said indoxyl phosphate and nitroblue tetrazolium to a colored product on said membrane; d) directing a solution comprising citric acid through said membrane; and e) determining the presence of said antigen in said first liquid by detecting said colored product on said membrane.
Claim 8
Independent Claim
147 words
A method for determining a viral antigen in a liquid comprising: a) combining a first liquid suspected of containing a viral antigen with a membrane coated with an inert protein and with an antibody specific for said antigen having alkaline phosphatase conjugated thereto whereby said viral antigen attaches to said coated membrane and to said antibody to give a bound fraction including said alkaline phosphatase on said membrane; b) separating said membrane from said first liquid by causing said first liquid to pass through said membrane; c) passing a second liquid containing indoxyl phosphate and nitroblue tetrazolium through said membrane, said alkaline phosphatase converting said indoxyl phosphate and nitroblue tetrazolium to a colored product on said membrane; d) directing a solution comprising citric acid through said membrane; and e) determining the presence of said antigen in said first liquid by detecting said colored product on said membrane.
Claim 9
Dependent Claim
58 words
A kit of materials for performing an assay for a ligand in a liquid comprising a membrane coated with at least one of an inert protein and a first antiligand, a tracer comprising a hydrolase conjugated to one of said ligand and a second antiligand, a substrate for said enzyme and a color stabilizing reagent comprising an acid.
Claim 10
Dependent Claim
58 words
A kit of materials for performing an assay for a ligand in a liquid comprising a membrane coated with at least one of an inert protein and a first antiligand, a tracer comprising a hydrolase conjugated to one of said ligand and a second antiligand, a substrate for said enzyme and a color stabilizing reagent comprising an acid.
Claim 11
Dependent Claim
13 words
The kit of Claim 16 wherein said substrate comprises a derivative of indoxyl.
Claim 12
Dependent Claim
13 words
The kit of Claim 19 wherein said substrate further comprises a tetrazolium salt.
Claim 13
Dependent Claim
17 words
The kit of Claim 16 further comprising a housing containing an absorbent material positioned adjacent said membrane.
References Cited (Backward Citations)
No citation records indexed.
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