EP0258963A2
Expired / Lapsed
EP
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Colloidal gold immunoassay
Assignee: Ortho Clinical Diagnostics Inc
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Filing: 1987-06-08
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Granted: —
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Expires: 2007-06-08
Abstract
Abstract A new immunoassay method for providing sensitive and rapid detection of ligands in body fluids utilizing colloidal gold labeled reagents and a matrix membrane having an immunologically active component therein. All liquid materials brought into contact with one side of the membrane flow through the membrane into an absorbent material in physical and fluid communication with the other side of the membrane. Reactions may be visually detected and in the case of hCG, a sensitivity of 50 mIU or less may be had within a total assay and manipulation time of one and a-half minutes.
Inventors
- 👤 Henry A. Graham, Jr.
- 👤 Dennis M. Mochnal
- 👤 Chi-Deu Chang
- 👤 Jemo Kang
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 22:55
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/58; G01N33/585; G01N33/53; G01N33/543; G01N33/54366; G01N33/74; G01N33/76
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
132 words
A method for detecting a ligand in a sample comprising the steps of: a) providing a porous membrane having a tortuous path therethrough and further having attached thereto a ligand binding partner, said membrane having a first side and a second side, said second side being in physical contact with an absorbent material for absorbing fluids brought into contact with said membrane, whereby fluid communication therebetween is established. b) contacting the first side of said membrane with said sample and, simultaneously or successively, with a ligand binding partner or ligand labelled directly or indirectly with collodial gold whereby an immunological reaction is carried out; and c) observing said first side of said membrane for the presence of colour indicative of the presence of colloidal gold and of the ligand in the sample.
Claim 2
Independent Claim
132 words
A method for detecting a ligand in a sample comprising the steps of: a) providing a porous membrane having a tortuous path therethrough and further having attached thereto a ligand binding partner, said membrane having a first side and a second side, said second side being in physical contact with an absorbent material for absorbing fluids brought into contact with said membrane, whereby fluid communication therebetween is established. b) contacting the first side of said membrane with said sample and, simultaneously or successively, with a ligand binding partner or ligand labelled directly or indirectly with collodial gold whereby an immunological reaction is carried out; and c) observing said first side of said membrane for the presence of colour indicative of the presence of colloidal gold and of the ligand in the sample.
Claim 3
Dependent Claim
67 words
The method of claim 1, wherein: the ligand is an antigen having at least two epitopic sites; the ligand binding partner in step a) is an immunoglobulin specific for a first epitopic site on the antigen; and the ligand binding partner in step b) is an immunoglobulin specific for a second epitopic site on the antigen, the second immunoglobulin being labelled directly or indirectly with colloidal gold.
Claim 4
Dependent Claim
10 words
The method of claim 2, wherein the antigen is hCG.
Claim 5
Dependent Claim
57 words
The method of claim 1, wherein: the ligand is an antigen; the ligand binding partner in step a) is an immunoglobulin specific for the antigen; and the ligand in step b) is a ligand, labelled directly or indirectly with colloid gold, which competes with the ligand in the sample and which is applied simultaneously with the sample.
Claim 6
Dependent Claim
51 words
The method of claim 1, wherein: the ligand is an antibody; the ligand binding partner in step a) is an antigen for which the antibody is specific; and the ligand binding partner in step b) is an immunoglobulin, labelled directly or indirectly with colloidal gold, which is specific for the antibody.
Claim 7
Independent Claim
45 words
The method of any one of claims 1 to 5, wherein, after the application of the ligand or ligand binding partner, labelled directly or indirectly with colloidal gold, a wash solution for removing unbound colloidal gold is applied to the first side of the membrane.
Claim 8
Independent Claim
25 words
The method of any one of claims 1 to 6, wherein said colloidal gold has a size within the range of 20 to 92 nm.
Claim 9
Dependent Claim
20 words
The method of claim 7, wherein said colloidal gold has a size within the range of 30 to 60 nm.
Claim 10
Independent Claim
31 words
The method of any one of claims 1 to 8, wherein said absorbent material is cellulose, cellulose acetate, rayon/cotton, polyethylene microporous plastic, polypropylene microporous plastic, glass microfibers, or cotton linter fibers.
Claim 11
Independent Claim
22 words
The method of any one of claims 1 to 9, wherein the membrane comprises activated Nylon 66, nitrocellulose or activated polyvinylidine difluoride.
Claim 12
Independent Claim
65 words
The method of any one of claims 1 to 10, wherein: a ligand having specificity equivalent to the ligand in the sample is also attached to the membrane; and the equivalent ligand and the ligand binding partner in step a) form a pattern which is visually detectable if the ligand is present in the sample and the ligand binding partner in step a) is working.
Claim 13
Independent Claim
31 words
The method of any one of claims 1 to 11, wherein said membrane is incubated for a period of less than five minutes after it has been contacted by the sample.
Claim 14
Independent Claim
44 words
The method of any one of claims 1 to 12, wherein the entire method is performed in a time period equal to the incubation period, if any, and the time required for the contacting steps, the latter generally totalling less than about 30 seconds.
Claim 15
Independent Claim
24 words
The method of any one of claims 1 to 13, wherein said membrane further comprises a built-in calibrator for said ligand to be detected.
Claim 16
Dependent Claim
93 words
A kit for use in an assay for the detection of a ligand in a fluid sample comprising: a membrane having a ligand binding partner for binding to the ligand to be detected in a first zone; an absorbent material in fluid communication with said membrane for absorbing fluids brought into contact with said membrane; and a container having a liquid reagent comprising colloidal gold labelled ligand for binding to the ligand binding partner on the membrane in a competitive assay or to the ligand in the fluid sample in a sandwich assay.
Claim 17
Dependent Claim
93 words
A kit for use in an assay for the detection of a ligand in a fluid sample comprising: a membrane having a ligand binding partner for binding to the ligand to be detected in a first zone; an absorbent material in fluid communication with said membrane for absorbing fluids brought into contact with said membrane; and a container having a liquid reagent comprising colloidal gold labelled ligand for binding to the ligand binding partner on the membrane in a competitive assay or to the ligand in the fluid sample in a sandwich assay.
Claim 18
Dependent Claim
19 words
The kit of claim 15, wherein said membrane has a second zone capable of binding with the liquid reagent.
References Cited (Backward Citations)
No citation records indexed.
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