Patent US2175470A successfully refreshed from Google Patents.
US4913883A
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Particle agglutination immunoassay apparatus
Assignee: Hitachi Ltd
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Filing: 1988-07-20
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Granted: 1990-04-03
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Expires: 2008-07-20
Abstract
Abstract The degree of agglutination is measured in a magnetic manner instead of optical manner. Microparticles are composed of a magnetic material and the agglutinated condition is measured using a magnetometer. The sizes and distribution of agglutinated materials formed by the antigen-antibody coupling reaction can be correctly measured without affected by light-scattering materials such as proteins or blood cells contained in the specimen, or by absorbant such as pigment, or by fluorescent material. Therefore, the concentration of antigen is measured maintaining high precision.
Inventors
- 👤 Kazumichi Imai
- 👤 Daizo Tokinaga
- 👤 Koichi Yokosawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:55
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54313; G01N33/54326; G01N33/54333; G01N33/54366; G01N35/00; G01N35/0098
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
76 words
A particle agglutination immunoassay apparatus that measures the concentration of antigen in a specimen by measuring the agglutination of microparticles formed by the reaction of said antigen with antibody coupled to the surfaces of microparticles, the improvement comprising: means which disperses agglutinated masses of microparticles formed by the reaction and moves the agglutinated masses together with the flow of liquid; and detect means which magnetically measures the sizes of agglutinated masses in the flow of liquid.
Claim 2
Dependent Claim
76 words
A particle agglutination immunoassay apparatus that measures the concentration of antigen in a specimen by measuring the agglutination of microparticles formed by the reaction of said antigen with antibody coupled to the surfaces of microparticles, the improvement comprising: means which disperses agglutinated masses of microparticles formed by the reaction and moves the agglutinated masses together with the flow of liquid; and detect means which magnetically measures the sizes of agglutinated masses in the flow of liquid.
Claim 3
Dependent Claim
21 words
A particle agglutination immunoassay apparatus according to claim 1, wherein the antibody is coupled by adsorption to the surfaces of microparticles.
Claim 4
Dependent Claim
29 words
A particle agglutination immunoassary apparatus according to claim 1, wherein the antibody is adsorbed onto the surfaces of microparticles, and then the antibody molecules are coupled through chemical crosslinking.
Claim 5
Dependent Claim
20 words
A particle agglutination immunoassay apparatus according to claim 1, wherein the antibody is chemically coupled to the surfaces of microparticles.
Claim 6
Dependent Claim
34 words
A particle agglutination immunoassary apparatus according to claim 1, wherein the surfaces of microparticles are coated with organic high molecules having functional groups, and the antibody is covalently bonded by using the functional groups.
Claim 7
Dependent Claim
21 words
A particle agglutination immunoassary apparatus according to claim 1, wherein the microparticles are composed of a material that can be magnetized.
Claim 8
Dependent Claim
20 words
A particle agglutination immunoassay apparatus according to claim 6, wherein the material that can be magnetized is a ferromagnetic material.
Claim 9
Dependent Claim
19 words
A particle agglutination immunoassay apparatus according to claim 6, wherein the material that can be magnetized is a metal.
Claim 10
Dependent Claim
29 words
A particle agglutination immunoassay apparatus according to claim 1, wherein the detecting unit consists of a magnet for magnetizing the microparticles and a magnetometer for measuring the magnetic moment.
Claim 11
Dependent Claim
16 words
A particle agglutination immunoassay apparatus according to claim 9, wherein the magnetometer is a SQUID magnetometer.
Claim 12
Dependent Claim
33 words
A particle agglutination immunoassay apparatus according to claim 10, wherein the magnetometer is comprised of detection coils that are arranged in two to three directions that meet at right angles with each other.
References Cited (Backward Citations)
US4663277A
Cited
US4661408A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-04-02 | 1993-10-02 | 1994-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-02 | 1997-10-02 | 1998-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-02 | 2001-10-02 | 2002-04-03 | $7700.00 | Window Closed / Lapsed |