US3652222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bilirubin assay
Assignee: American Monitor Corp
•
Filing: 1969-04-07
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Granted: 1972-03-28
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Expires: 1989-04-07
Abstract
Abstract The use of an acid solution of hydroxylamine in the analytical determination of the quantity of direct-reacting and indirectreacting bilirubin present in blood serum or body fluids, to block reaction of bilirubin after a certain stage of the assay and to prevent interference of substances contained in erythrocytes in the assay and to stabilize the azobilirubin color formed in the reaction, and also the use of a form of hydroxylamine in place of the unstable ascorbic acids used in certain assay procedures.
Inventors
- 👤 Jerry W Denney
- 👤 Larry W Denney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:17
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/26; Y; Y10; Y10S; Y10S436/00; Y10S436/903; Y10T; Y10T436/00; Y10T436/14; Y10T436/145555; Y10T436/146666
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
23 words
The method as set forth in claim 1, in which the acid solution of hydroxylamine is prepared by adding hydroxylamine hydrochloride to water.
Claim 2
Dependent Claim
18 words
The method as set forth in claim 1, in which the bilirubin assay is an alkaline azobilirubin procedure.
Claim 3
Dependent Claim
22 words
The method as set forth in claim 1, wherein the hydroxylamine is added to the reactant solution in place of ascorbic acid.
Claim 4
Dependent Claim
24 words
The method as set forth in claim 1, in which the acid hydroxylamine solution is prepared by dissolving an acid hydroxylamine salt in water.
Claim 5
Dependent Claim
56 words
In a method for colorimetric or spectrophotometric bilirubin assay, in which the color of azobilirubin formed from the coupling reaction of an azo reagent with bilirubin is measured, the improvement comprising using hydroxylamine in the reactant solution after the azobilirubin has formed therein, the hydroxylamine having been maintained stable prior to such use by being acidic.
Claim 6
Dependent Claim
18 words
The method as set forth in claim 6, in which the bilirubin assay is an alkaline azobilirubin procedure.
Claim 7
Dependent Claim
18 words
The method as set forth in claim 6, wherein the hydroxylamine is used in place of ascorbic acid.
Claim 8
Dependent Claim
63 words
In a method of bilirubin assay involving the measurement of the blue color of azobilirubin formed by the reaction of bilirubin and an azo reagent, the improvement comprising using hydroxylamine in a concentration which gives the same final concentration of hydroxylamine as when a solution which is 13 molar or greater of the hydroxylamine is substituted for ascorbic acid in a Jendrassik-Grof procedure.
References Cited (Backward Citations)
US3348920A
Cited
US3511607A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-28 | 1975-09-27 | 1976-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-28 | 1979-09-27 | 1980-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-28 | 1983-09-27 | 1984-03-28 | $7700.00 | Window Closed / Lapsed |