US4160818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorimetric immunoassay for diphenylhydantoin
Assignee: Bayer Corp
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Filing: 1977-04-12
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Granted: 1979-07-10
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Expires: 1997-04-12
Abstract
Abstract Substituted hydantoin drugs (for example phenytoin) and tricyclic antidepressant drugs (for example nortriptyline) are assayed by mixing them with a fluorescent labelled compound and antibodies, and measuring the fluorescence of the mixture. The assay does not necessitate any separation step and may be effected by continuous-flow techniques.
Inventors
- 👤 David S. Smith
- 👤 Adrienne R. McGregor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:09
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/94; G01N33/9473; Y; Y10; Y10S; Y10S436/00; Y10S436/80; Y10S436/815
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
117 words
A method of assaying a biological fluid sample for a hydantoin or a closely related hydantoin structured compound, said method comprising the steps of: a. forming a mixture of said biological fluid sample containing said compound to-be-assayed with: (1) anti-compound antibodies, and (2) a fluorescent-labelled substituted compound, said substituted compound generally having little or no resemblance to said compound to-be-assayed prior to labelling but, having sufficient similarity to said compound to-be-assayed after labelling, so as to be bindable with said anti-compound antibodies, said anti-compound antibodies binding both with said compound to-be-assayed and said fluorescent-labelled substituted compound; and b. determining the amount of said compound in the fluid sample by measuring the fluorescence of said fluorescent-labelled substituted compound.
Claim 2
Independent Claim
117 words
A method of assaying a biological fluid sample for a hydantoin or a closely related hydantoin structured compound, said method comprising the steps of: a. forming a mixture of said biological fluid sample containing said compound to-be-assayed with: (1) anti-compound antibodies, and (2) a fluorescent-labelled substituted compound, said substituted compound generally having little or no resemblance to said compound to-be-assayed prior to labelling but, having sufficient similarity to said compound to-be-assayed after labelling, so as to be bindable with said anti-compound antibodies, said anti-compound antibodies binding both with said compound to-be-assayed and said fluorescent-labelled substituted compound; and b. determining the amount of said compound in the fluid sample by measuring the fluorescence of said fluorescent-labelled substituted compound.
Claim 3
Dependent Claim
38 words
The method according to claim 1, wherein the compound under assay is further selected from a group consisting of: diphenylhydantoin, albutoin, aloxidone, 5-(α,β-dibromophenethyl)-5-methylhydantoin, 5,5-diphenyl-2-thiohydantoin, ethadione, ethosuximide, ethatoin, 5-ethyl-5-phenylhydantoin, mephenytoin, methetoin, methsuximide, 3-methyl-5-phenyl-hydantoin, paramethadione, pemoline, phensuximide, tetrantoin, and trimethadione.
Claim 4
Dependent Claim
32 words
The method according to claim 1, wherein the fluorescent-labelled substituted compound is labelled with a fluorescent label which is selected from a group consisting of: fluorescein, dansyl, rhodamine, fluorescamine, pyrene and 2-methoxy-2,4-diphenyl-3(2H)-furanone.
Claim 5
Dependent Claim
42 words
The method according to claim 1, wherein the measurement of the fluorescence of the mixture is compared with the fluorescence of standard mixtures containing known amounts of the compound under assay, and the amount of compound in the sample is thereby determined.
Claim 6
Dependent Claim
22 words
The method of claim 1, further comprising the step of: c. adding pepsin to said biological sample prior to forming said mixture.
Claim 7
Dependent Claim
30 words
The method of assaying a biological fluid sample of claim 1, further comprising the step of: c. flowing said mixture past a fluorimeter to measure the fluorescence of said mixture.
Claim 8
Dependent Claim
19 words
The method of claim 1, wherein the compound to-be-assayed is diphenylhydantoin, and said fluorescent-labelled substituted compound is fluorescein thiocarbamyl-(α,α-diphenylglycine).
Claim 9
Dependent Claim
16 words
The method of claim 1, wherein said anti-compound antibodies were raised against said fluorescent-labelled substituted compound.
Claim 10
Dependent Claim
13 words
A method according to claim 1, wherein the fluorescent-labelled substituted compound is fluoresceinthiocarbamyl-(α,α-diphenylglycine).
Claim 11
Dependent Claim
19 words
A method according to claim 9, wherein the fluorescein thiocarbamyl-(α,α-diphenylglycine) has been obtained by reacting α,α-diphenylglycine with fluorescein isothiocyanate.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-07-09 | 1983-01-08 | 1983-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-07-09 | 1987-01-08 | 1987-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-07-09 | 1991-01-08 | 1991-07-10 | $7700.00 | Window Closed / Lapsed |