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US4292404A
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Method for determining the activity of the angiotensin-converting enzyme
Assignee: Fujirebio Inc
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Filing: 1980-09-11
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Granted: 1981-09-29
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Expires: 2000-09-11
Abstract
Abstract Method for determining the activity of the angiotensin-converting enzyme comprising the steps of: (1) mixing a liquid containing the angiotensin-converting enzyme with a reagent consisting essentially of X-hippuryl-L-histidyl-L-leucine, hippuricase, peroxidase, 4-aminoantipyrine and H 2 O 2 , and (2) colorimetrically measuring the concentration of quinonimine dye produced in step (1).
Inventors
- 👤 Yasushi Kasahara
- 👤 Yoshihiro Ashihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:21
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/26; C12Q1/28; C07; C07K; C07K5/00; C07K5/04; C07K5/08; C07K5/0802; C07K5/0804; C07K5/0806; C12Q1/34; C12Q1/37; C12Q2326/00; C12Q2326/90; C12Q2326/96; C12Q2337/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
78 words
A method for determining the activity of the angiotensin-converting enzyme comprising the steps of: (1) mixing a liquid containing the angiotensin-converting enzyme with a reagent consisting essentially of X-hippuryl-L-histidyl-L-leucine having the formula ##STR2## wherein X is OH, NH 2 or N(CH 3 ) 2 , and with hippuricase, peroxidase, 4-aminoantipyrine and H 2 O 2 , under reaction conditions effective to form quinonimine dye, and (2) colorimetrically measuring the concentration of said quinonimine dye produced in step (1).
Claim 2
Independent Claim
78 words
A method for determining the activity of the angiotensin-converting enzyme comprising the steps of: (1) mixing a liquid containing the angiotensin-converting enzyme with a reagent consisting essentially of X-hippuryl-L-histidyl-L-leucine having the formula ##STR2## wherein X is OH, NH 2 or N(CH 3 ) 2 , and with hippuricase, peroxidase, 4-aminoantipyrine and H 2 O 2 , under reaction conditions effective to form quinonimine dye, and (2) colorimetrically measuring the concentration of said quinonimine dye produced in step (1).
Claim 3
Dependent Claim
11 words
The method according to claim 1 wherein said X-hippuryl-L-histidyl-L-leucine is p-hydroxyhippuryl-L-histidyl-L-leucine.
Claim 4
Dependent Claim
11 words
The method according to claim 1 wherein said X-hippuryl-L-histidyl-L-leucine is p-aminohippuryl-L-histidyl-L-leucine.
Claim 5
Dependent Claim
11 words
The method according to claim 1 wherein said X-hippuryl-L-histidyl-L-leucine is p-dimethylaminohippuryl-L-histidyl-L-leucine.
References Cited (Backward Citations)
US4108726A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-09-28 | 1985-03-30 | 1985-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-28 | 1989-03-30 | 1989-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-28 | 1993-03-30 | 1993-09-29 | $7700.00 | Window Closed / Lapsed |