US4608335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Enzymatic urea assay
Assignee: Miles Italiana SpA
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Filing: 1984-06-08
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Granted: 1986-08-26
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Expires: 2004-06-08
Abstract
Abstract A composition, device and method useful as an enzymatic urea assay based on the use of urea amidolyase comprising urea amidolyase, pyruvate kinase, pyruvate oxidase, mono and divalent cations, phosphoenolpyruvate, thyamine pyrophosphate, ATP, bicarbonate, phosphate, a color indicator system and optionally inorganic phosphate, a buffer having a pH range of from about 6.5 to 9.5, and sodium or potassium ferrocyanide. After contacting the test solution or body fluid sample with the assay composition, reading can be accomplished visually or instrumentally.
Inventors
- 👤 Piero Fossati
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:08
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/58
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
38 words
A composition for the enzymatic determination of urea in a fluid sample, which composition comprises urea amidolyase, pyruvate kinase, pyruvate oxidase, a divalent cation, a monovalent cation, phosphoenolpyruvate, thyamine pyrophosphate, adenosine triphosphate, bicarbonate, and a color indicator system.
Claim 2
Dependent Claim
38 words
A composition for the enzymatic determination of urea in a fluid sample, which composition comprises urea amidolyase, pyruvate kinase, pyruvate oxidase, a divalent cation, a monovalent cation, phosphoenolpyruvate, thyamine pyrophosphate, adenosine triphosphate, bicarbonate, and a color indicator system.
Claim 3
Dependent Claim
12 words
The composition of claim 1 wherein the composition additionally comprises inorganic phosphate.
Claim 4
Dependent Claim
20 words
The composition of claim 1 wherein the color indicator system is a peroxidatively active agent and a color indicator component.
Claim 5
Dependent Claim
12 words
The composition of claim 3 wherein the peroxidatively active agent is peroxidase.
Claim 6
Dependent Claim
14 words
The composition of claim 3 wherein the color indicator component is a reversible indicator.
Claim 7
Dependent Claim
14 words
The composition of claim 3 wherein the color indicator component is an oxidative coupler.
Claim 8
Dependent Claim
20 words
The composition of claim 6 wherein the oxidative coupler comprises 4-aminophenazone and a phenol, a naphthol, or an aromatic amine.
Claim 9
Dependent Claim
18 words
The composition of claim 1 and a buffer having a pH range of from about 6.5 to 9.5.
Claim 10
Dependent Claim
10 words
The composition of claim 1 and sodium or potassium ferrocyanide.
Claim 11
Dependent Claim
24 words
A test device for the determination of urea which device comprises an inert carrier incorporated with the composition of any one of claims 1-9.
Claim 12
Dependent Claim
34 words
A method of making the test device of claim 10 wherein the composition is incorporated with the carrier by impregnating the carrier with a solution of said composition, followed by drying the impregnated carrier.
Claim 13
Dependent Claim
31 words
A process for the determination of urea in a fluid sample which comprises contacting said sample with the composition of any one of claims 1-9 and observing any resultant color formed.
Claim 14
Dependent Claim
29 words
A process for the determination of urea in a fluid sample which comprises contacting said sample with the test device of claim 10 and observing any resultant color formed.
Claim 15
Dependent Claim
46 words
A composition for the enzymatic determination of urea in a fluid sample, which composition comprises urea amidolyase, pyruvate kinase, pyruvate oxidase, MgSO 4 , K 2 HPO 4 , phosphoenolpyruvate, thiamine pyrophosphate, adenosine triphosphate and KHCO 3 to liberate hydrogen peroxide; peroxidase, 4-aminophenazone, and 2-hydroxyphenylacetic acid.
Claim 16
Dependent Claim
46 words
A composition for the enzymatic determination of urea in a fluid sample, which composition comprises urea amidolyase, pyruvate kinase, pyruvate oxidase, MgSO 4 , K 2 HPO 4 , phosphoenolpyruvate, thiamine pyrophosphate, adenosine triphosphate and KHCO 3 to liberate hydrogen peroxide; peroxidase, 4-aminophenazone, and 2-hydroxyphenylacetic acid.
Claim 17
Dependent Claim
18 words
The composition of claim 14 and a buffer having a pH range of from about 6.5 to 9.9.
Claim 18
Dependent Claim
10 words
The composition of claim 14 and sodium or potassium ferrocyanide.
Claim 19
Independent Claim
25 words
A device for the determination of urea which device comprises an inert carrier incorporated with the composition of any one of claims 14 to 16.
Claim 20
Dependent Claim
34 words
A method of making the test device of claim 17 wherein the composition is incorporated with the carrier by impregnating the carrier with a solution of said composition, followed by drying the impregnated carrier.
Claim 21
Dependent Claim
33 words
A process for the determination of urea in a fluid sample which comprises contacting said sample with the composition of any one of claims 14 to 16 and observing any resultant color formed.
Claim 22
Dependent Claim
29 words
A process for the determination of urea in a fluid sample which comprises contacting said sample with the test device of claim 17 and observing any resultant color formed.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-08-25 | 1990-02-24 | 1990-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-25 | 1994-02-24 | 1994-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-25 | 1998-02-24 | 1998-08-26 | $7700.00 | Window Closed / Lapsed |