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US4511651A
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Reagent composition and assay for the determination of γ-glutamyltransferase activity
Assignee: INDIANA DEVELOPMENT FINANCE AUTHORITY
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Filing: 1982-07-30
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Granted: 1985-04-16
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Expires: 2002-07-30
Abstract
Abstract An improved diagnostic assay and stabilized reagent composition for the determination of γ-glutamyltransferase activity in biological specimens using a buffered solution of γ-glutamyl-p-nitroanilide and glycylglycine, wherein β-cyclodextrin and preferably also dimethylsulfoxide have been added thereto.
Inventors
- 👤 Larry E. Beaty
- 👤 Steven M. Lanham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:14
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/48; Y; Y10; Y10S; Y10S435/00; Y10S435/81
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
58 words
A reagent composition for the determination of the enzyme γ-glutamyltransferase in a fluid, comprised of: (a) an enzymatically reactive amount of γ-glutamyl-p-nitroanilide; (b) a buffer; (c) a glycylglycine; and (d) a cyclodextrin from the group consisting of β-cyclodextrin and cyclodextrins substituted with 1 to 4 amino groups in an amount between about 1 and 19 grams per liter.
Claim 2
Dependent Claim
58 words
A reagent composition for the determination of the enzyme γ-glutamyltransferase in a fluid, comprised of: (a) an enzymatically reactive amount of γ-glutamyl-p-nitroanilide; (b) a buffer; (c) a glycylglycine; and (d) a cyclodextrin from the group consisting of β-cyclodextrin and cyclodextrins substituted with 1 to 4 amino groups in an amount between about 1 and 19 grams per liter.
Claim 3
Dependent Claim
20 words
A reagent composition as recited in claim 1, further comprising dimethylsulfoxide in an amount between about 0.5 and 10 percent.
Claim 4
Independent Claim
87 words
A method for the determination of the enzyme γ-glutamyltransferase in a fluid, comprising the steps of: (a) combining a sample of said fluid with a reagent to form a reaction mixture, said reagent comprising: (i) an enzymatically reactive amount of γ-glutamyl-p-nitroanilide, (ii) a buffer, (iii) glycylglycine, and (iv) a cyclodextrin from the group consisting of β-cyclodextrin and cyclodextrins substituted with 1 to 4 amino groups in an amount between about 1 and 19 grams per liter; and (b) measuring the change in absorbance of said reaction mixture.
Claim 5
Independent Claim
87 words
A method for the determination of the enzyme γ-glutamyltransferase in a fluid, comprising the steps of: (a) combining a sample of said fluid with a reagent to form a reaction mixture, said reagent comprising: (i) an enzymatically reactive amount of γ-glutamyl-p-nitroanilide, (ii) a buffer, (iii) glycylglycine, and (iv) a cyclodextrin from the group consisting of β-cyclodextrin and cyclodextrins substituted with 1 to 4 amino groups in an amount between about 1 and 19 grams per liter; and (b) measuring the change in absorbance of said reaction mixture.
Claim 6
Dependent Claim
21 words
A method as recited in claim 3, said reagent further comprising dimethylsulfoxide in an amount between about 0.5 and 10 percent.
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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) | 1988-04-15 | 1988-10-15 | 1989-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-15 | 1992-10-15 | 1993-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-15 | 1996-10-15 | 1997-04-16 | $7700.00 | Window Closed / Lapsed |