US5057414A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the determination of the activity of serine proteases or serine protease inhibitors
Assignee: Siemens Healthcare Diagnostics Products GmbH
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Filing: 1988-07-01
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Granted: 1991-10-15
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Expires: 2008-07-01
Abstract
Abstract The invention relates to a method for the determination of the activity of serine proteases and serine protease inhibitors in plasma or other biological fluids. The only methods hitherto available for rapid and accurate determination of the content of serine proteases or serine protease inhibitors have been very time-consuming and methodologically demanding. In the method according to the invention for the determination of the activity of serine proteases or serine protease inhibitors, specific inhibitors are inactivated by addition of at least one oxidizing agent and, where appropriate, at least one detergent. The addition of an omega-aminocarboxylic acid enhances and observed effects when the serine protease is plasmin.
Inventors
- 👤 Thomas Stief
- 👤 Norbert Heimburger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:44
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/34; C12Q1/37; C12Q1/56; G; G01; G01N; G01N2333/00; G01N2333/81; G01N2333/8107; G01N2333/811; G01N2333/8121; G01N2333/8132
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
120 words
A method for the determination of the activity of serine proteases or serine protease inhibitors in a sample of plasma or other biological fluids comprising the steps of: (i) adding at least one oxidizing agent to said sample which oxidizes methionine to methionine sulfoxide at a pH of 7.5 to 8.8; (ii) adding simultaneously o rafter a preincubation period a plasminogen activator and a first substrate for said plasminogen activator, said first substrate being activated by a said plasminogen activator to yield an enzyme which can be detected by means of a second substrate; and (iii) bringing said activated first substrate into contact with said second substrate which second substrate can be detected after conversion by said activated first substrate.
Claim 2
Independent Claim
120 words
A method for the determination of the activity of serine proteases or serine protease inhibitors in a sample of plasma or other biological fluids comprising the steps of: (i) adding at least one oxidizing agent to said sample which oxidizes methionine to methionine sulfoxide at a pH of 7.5 to 8.8; (ii) adding simultaneously o rafter a preincubation period a plasminogen activator and a first substrate for said plasminogen activator, said first substrate being activated by a said plasminogen activator to yield an enzyme which can be detected by means of a second substrate; and (iii) bringing said activated first substrate into contact with said second substrate which second substrate can be detected after conversion by said activated first substrate.
Claim 3
Dependent Claim
14 words
The method of claim 1, wherein said serine protease inhibitors are plasminogen activator inhibitors.
Claim 4
Dependent Claim
59 words
The method of claim 1, further comprising the steps, of: (iv) adding a defined quantity of plasminogen activator to said sample; and (v) determining the quantity of plasminogen activator inhibitor by computing the deference of the activity of added plasminogen activator activity and the remaining plasminogen activator activity after inhibition by said plasminogen activator inhibitor contained in said sample.
Claim 5
Dependent Claim
20 words
The method of claim 1, wherein said detection after conversion by said activated first substrate is conducted by photometric means.
Claim 6
Dependent Claim
16 words
The method of claim 1, wherein said serine protease is a plasminogen activator, plasmin or thrombin.
Claim 7
Dependent Claim
42 words
The method of claim 1, wherein said oxidizing agent is selected from the group consisting of halogeno amines and salts thereof, halogeno imines and salts thereof, halogeno amides and salts thereof, halogeno imides and salts thereof, and halogeno hydroxyls and salts thereof.
Claim 8
Dependent Claim
37 words
The method of claim 1, wherein said oxidizing agent is selected form the group consisting of hydrogen peroxide, salts of peroxomonosulfuric acid, salts of peroxodisulfuric acid, oxidized gluthathione, chloramine t, chloramine B, salts of HOCl and N-chlorosuccinimide.
Claim 9
Dependent Claim
21 words
The method of claim 1, further comprising the step of adding at least one omega-amino carboxylic acid prior to step (ii).
Claim 10
Dependent Claim
19 words
The method of claim 1, further comprising the step of adding at least one detergent prior to step (ii).
Claim 11
Dependent Claim
29 words
The method of claim 1, further comprising the step of adding at least one omega-amino carboxylic acid and at least one detergent to said sample prior to step (ii).
Claim 12
Dependent Claim
19 words
The method of claim 1, wherein said first substrate is plasminogen or one of its natural or synthetic derivatives.
Claim 13
Dependent Claim
11 words
The method of claim 1, wherein said first substrate is miniplasminogen.
Claim 14
Dependent Claim
11 words
The method of claim 1, wherein said second substrate is plasmin.
Claim 15
Dependent Claim
22 words
The method of claim 2, wherein said serine proease is selected form the group consisting of a plasminogen activator, plasmin and thrombin.
Claim 16
Dependent Claim
42 words
The method of claim 2, wherein said oxidizing agent is selected from the group consisting of halogeno amines and salts thereof, halogeno imines and salts thereof, halogeno amides and salts thereof, halogeno imides and salts thereof, and halogeno hydroxyls and salts thereof.
Claim 17
Dependent Claim
37 words
The method of claim 2, wherein said oxidizing agent is selected from the group consisting of hydrogen perioxide, salts of peroxomonosulfuric acid, salts of peroxodisulfuric acid, oxidized gluthathione, chloramine T, chloramine B, salts of HOCl and N-chlorosuccinimide.
Claim 18
Dependent Claim
21 words
The method of claim 2, further comprising the step of adding at least one omega-amino carboxylic acid prior to step (ii).
Claim 19
Dependent Claim
19 words
The method of claim 2, further comprising the step of adding at least one detergent prior to step (ii).
Claim 20
Dependent Claim
29 words
The method of claim 2, further comprising the step of adding at least one omega-amino carboxylic acid and at least one detergent to said sample prior to step (ii).
Claim 21
Dependent Claim
28 words
The method of claim 2, wherein said serine protease inhibitor is a placental type plasminogen activator inhibitor (2) further comprising the step of adding polycation to said sample.
Claim 22
Dependent Claim
11 words
The method of claim 2, wherein said polycations are protamine chloride.
Claim 23
Dependent Claim
14 words
The method of claim 2, wherein said serine protease is a single chain urokinase.
Claim 24
Dependent Claim
29 words
The method of claim 2 further comprising the step of adding kallikrein or a surface activator to said sample simultaneously with said oxidizing agent or after said preincubation period.
References Cited (Backward Citations)
US4493891A
Cited
US4818690A
Cited
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