US4692406A
Expired / Lapsed
US
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Process and a reagent for the simultaneous determination of fibrinogen and fibrinogen fission products in plasma
Assignee: Roche Diagnostics GmbH
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Filing: 1984-08-20
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Granted: 1987-09-08
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Expires: 2004-08-20
Abstract
Abstract The present invention provides a process for the simultaneous determination of fibrinogen and fibrinogen fission products in plasma, wherein 0.01 to 1 U of a snake venom enzyme with a thrombin-like effectiveness is aded per ml. of sample plasma, then there is measured the period of time between the addition of the enzyme and the commencement of a turbidity formation as a measure for the amount of fibrinogen fission products and subsequently there is measured the speed of the turbidity formation as a measure of the amount of fibrinogen. The present invention also provides a reagent for the simultaneous determination of fibrinogen and fibrinogen fission products, wherein it comprises 0.01 to 10 U snake venon enzyme with thrombin-like effectiveness per ml. of sample plasma, 0.5 to 4% by weight of a water-soluble polyalcohol, 1 to 20 mMole/liter of calcium ions and 0.05 to 0.3 mole/liter of buffer of pH 7.0 to 8.0, referred to the solution ready for use, as well as optionally a detergent.
Inventors
- 👤 Udo Becker
- 👤 Peter Roeschlau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:16
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/56; G; G01; G01N; G01N2333/00; G01N2333/435; G01N2333/46; G01N2333/4609; G01N2333/4613; G01N2333/462; G01N2333/4623; G01N2333/4626; G01N2333/745; G01N2333/75; G01N2333/90; G01N2333/914; G01N2333/948; G01N2333/974; Y; Y10; Y10S; Y10S435/00; Y10S435/81
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
77 words
A process for the simultaneous determination of fibrinogen and fibrinogen fission products in plasma, comprising adding 0.01 to 1U of a snake venom enzyme with thrombin-like activity per ml. of sample plasma, measuring the period of time between the addition of the enzyme and the commencement of a turbidity formation as a measure of the amount of fibrinogen fission products, and subsequently measuring the speed of the turbidity formation as a measure of the amount of fibrinogen.
Claim 2
Dependent Claim
77 words
A process for the simultaneous determination of fibrinogen and fibrinogen fission products in plasma, comprising adding 0.01 to 1U of a snake venom enzyme with thrombin-like activity per ml. of sample plasma, measuring the period of time between the addition of the enzyme and the commencement of a turbidity formation as a measure of the amount of fibrinogen fission products, and subsequently measuring the speed of the turbidity formation as a measure of the amount of fibrinogen.
Claim 3
Dependent Claim
33 words
The process of claim 1, wherein said enzyme is snake venom enzyme batroxobin, the venom enzyme of the Malayan pit viper (Aqkistrodon rhodostoma) or the venom enzyme of the copperhead snake (Agkistrodon contortix)
Claim 4
Dependent Claim
17 words
The process of claim 1, wherein 0.5 to 4% by weight of a water-soluble polyalcohol is added.
Claim 5
Dependent Claim
22 words
The process of claim 3, wherein the polyalcohol used is starch, dextran, polyvinyl alcohol, polyethylene glycol, a sugar or a sugar polymer.
Claim 6
Dependent Claim
18 words
The process of claim 4, wherein the polyethylene glycol has a molecular weight of from 4,000 to 22,000.
Claim 7
Dependent Claim
20 words
The process of claim 1 wherein the determination is carried out at a pH value of from 7.0 to 9.0.
Claim 8
Dependent Claim
19 words
The process of claim 1 wherein the determination is carried out in a 0.05 to 0.3 mole/liter buffer solution.
Claim 9
Dependent Claim
19 words
The process of claim 1 wherein calcium ions are added in an amount of from 1 to 20 mMole/liter.
Claim 10
Dependent Claim
62 words
A reagent for the simultaneous determination of fibrinogen and fibrinogen fission products, comprising 0.01 to 1.0U snake venom enzyme with thrombin-like activity per ml. of sample plasma, 0.5 to 4% by weight of a water-soluble polyalcohol, 1 to 20 mMole/liter of calcium ions and 0.05 to 0.3 mole/liter of buffer of pH 7.0 to 8.0, referred to the solution ready for use.
Claim 11
Dependent Claim
62 words
A reagent for the simultaneous determination of fibrinogen and fibrinogen fission products, comprising 0.01 to 1.0U snake venom enzyme with thrombin-like activity per ml. of sample plasma, 0.5 to 4% by weight of a water-soluble polyalcohol, 1 to 20 mMole/liter of calcium ions and 0.05 to 0.3 mole/liter of buffer of pH 7.0 to 8.0, referred to the solution ready for use.
Claim 12
Dependent Claim
9 words
The reagent of claim 9 further comprising a detergent.
Claim 13
Dependent Claim
14 words
The reagent of claim 9 wherein a tris/HCl or a phosphate buffer is used.
Claim 14
Dependent Claim
14 words
The process of claim 7 wherein a tris/HCl or a phosphate buffer is used.
References Cited (Backward Citations)
US4245039A
Cited
US4289498A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-09-07 | 1991-03-09 | 1991-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-09-07 | 1995-03-09 | 1995-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-09-07 | 1999-03-09 | 1999-09-08 | $7700.00 | Window Closed / Lapsed |