US3933997A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solid phase radioimmunoassay of digoxin
Assignee: Bayer Corp
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Filing: 1974-03-01
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Granted: 1976-01-20
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Expires: 1994-03-01
Abstract
Abstract Clinically significant concentrations of digoxin can be determined by reacting an unknown amount of digoxin, a known amount of labelled digoxin, and a composite consisting of anti-digoxin antibodies coupled through an intermediate silane to magnetically responsive particles; magnetically separating the immunochemical complexes formed thereby, counting the radioactivity of either the separated products or remaining solution, and relating the count to a standard curve.
Inventors
- 👤 Leroy S. Hersh
- 👤 Sidney Yaverbaum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:21
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54313; G01N33/54326; G01N31/00; G01N31/16; Y; Y10; Y10S; Y10S436/00; Y10S436/804; Y10S436/815; Y10S436/817
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
88 words
A method of determining the concentration of digoxin in a solution comprising the steps of: A. reacting the solution, a known amount of radioactively labelled digoxin, and a composite consisting of anti-digoxin antibodies coupled chemically through an intermediate silane coupling agent to magnetically responsive inorganic particles, to form immunochemical complexes; B. magnetically separating the composite from the reaction solution; C. counting the radioactivity of either the removed composite or the remaining solution; and D. relating the count of step (C) to a standard to determine the digoxin concentration.
Claim 2
Independent Claim
88 words
A method of determining the concentration of digoxin in a solution comprising the steps of: A. reacting the solution, a known amount of radioactively labelled digoxin, and a composite consisting of anti-digoxin antibodies coupled chemically through an intermediate silane coupling agent to magnetically responsive inorganic particles, to form immunochemical complexes; B. magnetically separating the composite from the reaction solution; C. counting the radioactivity of either the removed composite or the remaining solution; and D. relating the count of step (C) to a standard to determine the digoxin concentration.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein the magnetically responsive particles are selected from the group consisting of Fe 3 O 4 , CoO, NiO, Mn 2 O 3 , finely divided iron particles, and finely divided nickel particles.
Claim 4
Dependent Claim
19 words
The method of claim 2 wherein the particles have an average particle size between about 1.5μ and about 10μ.
Claim 5
Dependent Claim
19 words
The method of claim 2 wherein the particles have a surface area of at least 10 m 2 /g.
Claim 6
Dependent Claim
38 words
The method of claim 1 wherein the composite of step (A) consists of the reaction product of anti-digoxin antibodies and silanized particles of Fe 3 O 4 which, prior to the reaction with the antibodies, had been diazotized.
Claim 7
Dependent Claim
26 words
The method of claim 1 wherein the inorganic particles consist of Fe 3 O 4 having an average particle size between about 1.5 and about 10μ.
Claim 8
Dependent Claim
44 words
An immunochemical composite suitable for use in determining clinically significant concentrations of digoxin and comprising anti-digoxin antibodies chemically coupled through an intermediate silane coupling agent to particles of Fe 3 O 4 having an average particle size between about 1.5 and about 10 microns.
Claim 9
Dependent Claim
44 words
An immunochemical composite suitable for use in determining clinically significant concentrations of digoxin and comprising anti-digoxin antibodies chemically coupled through an intermediate silane coupling agent to particles of Fe 3 O 4 having an average particle size between about 1.5 and about 10 microns.
References Cited (Backward Citations)
US3519538A
Cited
US3652761A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |