US4074972A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Urea assay
Assignee: INDIANA DEVELOPMENT FINANCE AUTHORITY
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Filing: 1976-11-10
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Granted: 1978-02-21
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Expires: 1996-11-10
Abstract
Abstract A urea assay or analysis process and reagents therefor, in which the assay involves a reaction between a sample of biological fluid and an acidic reagent solution of o-phthaldehyde and a chromogenic compound; the chromogenic compounds include certain substituted benzene compounds, certain substituted naphthalene compounds, certain aminopyrimidines, certain substituted quinolines, certain morpholino substituted quinolines and certain morpholino substituted naphthalenes.
Inventors
- 👤 Jerry W. Denney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:21
CPC Classifications
C; C07; C07D; C07D215/00; C07D215/02; C07D215/16; C07D215/38; C07D215/42; C07D215/46; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/62; Y; Y10; Y10T; Y10T436/00; Y10T436/17; Y10T436/171538
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
79 words
A process for the quantitation of urea in a fluid sample, in which the sample is reacted with an acidic solution of o-phthalaldehyde and an acidic solution of a chromogenic compound having the following general structure: ##STR7## where R 1 is --H or --CH 3 and where R 2 is --CH 3 or --C 2 H 5 or --H and where R 3 and R 4 are --H or --CH 3 and where n is 1, 2, or 3.
Claim 2
Dependent Claim
79 words
A process for the quantitation of urea in a fluid sample, in which the sample is reacted with an acidic solution of o-phthalaldehyde and an acidic solution of a chromogenic compound having the following general structure: ##STR7## where R 1 is --H or --CH 3 and where R 2 is --CH 3 or --C 2 H 5 or --H and where R 3 and R 4 are --H or --CH 3 and where n is 1, 2, or 3.
Claim 3
Dependent Claim
15 words
The process as defined in claim 1, in which the chromogenic compound used is 8-(4-amino-1-methylbutylamino)-6-methoxyquinoline.
Claim 4
Dependent Claim
90 words
A process for the quantitation of urea in a fluid sample, in which the sample is reacted with a reagent containing an acidic solution of o-phthalaldehyde and an acidic solution of a chromogenic compound of the general class of compounds which have the following general structure: ##STR8## Where R is --H or --CH 3 and where R 1 is --CH 3 , or --CH 2 CH 3 or --H or --CH 2 CH 2 --CH 3 where n is 1, 2, or 3 and where X is O or C.
Claim 5
Dependent Claim
90 words
A process for the quantitation of urea in a fluid sample, in which the sample is reacted with a reagent containing an acidic solution of o-phthalaldehyde and an acidic solution of a chromogenic compound of the general class of compounds which have the following general structure: ##STR8## Where R is --H or --CH 3 and where R 1 is --CH 3 , or --CH 2 CH 3 or --H or --CH 2 CH 2 --CH 3 where n is 1, 2, or 3 and where X is O or C.
Claim 6
Dependent Claim
15 words
The process as defined in claim 3, in which the chromogenic compound used is 8-(2-N-morpholinoethylamino)-6-methoxyquinoline.
References Cited (Backward Citations)
US3091571A
Cited
US3890099A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-20 | 1981-08-22 | 1982-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-20 | 1985-08-22 | 1986-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-20 | 1989-08-22 | 1990-02-21 | $7700.00 | Window Closed / Lapsed |