US4571383A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reagent for measuring direct bilirubin by enzymatic method and method for measurement thereof
Assignee: Azwell Inc
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Filing: 1983-12-19
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Granted: 1986-02-18
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Expires: 2003-12-19
Abstract
Abstract Reagent for the measurement of direct bilirubin comprising a buffer solution having a pH range of 3.5 to 4.5 which contains bilirubin oxidase, preferably in the form of a test kit consisting essentially of (i) a buffer solution having a pH range of 3.5 to 4.5, (ii-a) a lyophilized bilirubin oxidase, (ii-b) a buffer solution for dissolving the lyophilized bilirubin oxidase, and (iii) a standard serum containing a prescribed amount of bilirubin, and a method for measurement of direct bilirubin by using the reagent. The reagent and method are useful for diagnosis of various diseases, for example, various hepatic diseases (e.g. jaundice) and cholepathia.
Inventors
- 👤 Masaharu Takayama
- 👤 Seiichi Taniguchi
- 👤 Masayasu Enomoto
- 👤 Masahiro Muramoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:15
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/26
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
53 words
A diagnostic test kit having component reagents packaged together in a single package; the kit comprising the combination of a buffer solution having a pH range of 3.5 to 4.5, a lyophilized bilirubin oxidase, a buffer solution for dissolving the lyophilized bilirubin oxidase, and a standard serum containing a prescribed amount of bilirubin.
Claim 2
Dependent Claim
53 words
A diagnostic test kit having component reagents packaged together in a single package; the kit comprising the combination of a buffer solution having a pH range of 3.5 to 4.5, a lyophilized bilirubin oxidase, a buffer solution for dissolving the lyophilized bilirubin oxidase, and a standard serum containing a prescribed amount of bilirubin.
Claim 3
Dependent Claim
19 words
The kit according to claim 1, wherein the lyophilized bilirubin oxidase contains 1 to 10 units/test of bilirubin oxidase.
Claim 4
Dependent Claim
28 words
The kit according to claim 1, wherein the lyophilized bilirubin oxidase contains 0.025 to 3 units/test of bilirubin oxidase and also 10 to 500 μM/test of potassium ferricyanide.
Claim 5
Independent Claim
26 words
A method for measurement of direct bilirubin, which comprises reacting a test serum sample with bilirubin oxidase in a buffer solution of pH 3.5 to 4.5.
Claim 6
Independent Claim
26 words
A method for measurement of direct bilirubin, which comprises reacting a test serum sample with bilirubin oxidase in a buffer solution of pH 3.5 to 4.5.
Claim 7
Dependent Claim
14 words
The method according to claim 4, wherein the buffer solution has about pH 4.0.
Claim 8
Dependent Claim
39 words
The method according to claim 4, wherein the reaction with bilirubin oxidase is carried out at 37° C. for 10 to 30 minutes, followed by measuring the optical density of the reaction mixture at a wavelength of 460 nm.
Claim 9
Dependent Claim
34 words
A reagent for measurement of direct bilirubin, which comprise a lyophilized bilirubin oxidase and a buffer solution for dissolving the lyophilized bilirubin oxidase, said buffer solution having a pH range of 3.5 to 4.5.
Claim 10
Dependent Claim
34 words
A reagent for measurement of direct bilirubin, which comprise a lyophilized bilirubin oxidase and a buffer solution for dissolving the lyophilized bilirubin oxidase, said buffer solution having a pH range of 3.5 to 4.5.
Claim 11
Dependent Claim
19 words
The reagent according to claim 7, wherein the lyophilized bilirubin oxidase contains 1 to 10 units/test of bilirubin oxidase.
Claim 12
Dependent Claim
28 words
The reagent according to claim 7, wherein the lyophilized bilirubin oxidase contains 0.025 to 3 units/test of bilirubin oxidase and also 10 to 500 μM/test of potassium ferricyanide.
Claim 13
Dependent Claim
14 words
The reagent according to claim 7, wherein the bilirubin oxidase is Myrothecium-origin bilirubin oxidase.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-02-17 | 1989-08-19 | 1990-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-17 | 1993-08-19 | 1994-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-17 | 1997-08-19 | 1998-02-18 | $7700.00 | Window Closed / Lapsed |