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US5132226A
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Method for the determination of maleimide groups
Assignee: Merck Patent GmbH
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Filing: 1989-12-18
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Granted: 1992-07-21
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Expires: 2009-12-18
Abstract
Abstract A method and an agent for the determination of maleimide groups, comprising reacting a sample containing maleimide groups with a reagent containing thiol groups and then with a chromogen or fluorogen which reacts with thiol groups, and measuring the change in intensity.
Inventors
- 👤 Michael Dreher
- 👤 Heinz Hirsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:53
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; Y; Y10; Y10T; Y10T436/00; Y10T436/14; Y10T436/145555; Y10T436/17
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
63 words
A method for determining the number of functional reactive maleimide groups in a maleimide group-containing protein sample, comprising: (a) reacting a protein sample containing maleimide groups with a reagent containing thiol groups; (b) reacting the resultant mixture with a chromogen or fluorogen which reacts with unreacted thiol groups; and (c) measuring the resultant intensity of light or fluorescence of the chromogen or fluorogen.
Claim 2
Independent Claim
63 words
A method for determining the number of functional reactive maleimide groups in a maleimide group-containing protein sample, comprising: (a) reacting a protein sample containing maleimide groups with a reagent containing thiol groups; (b) reacting the resultant mixture with a chromogen or fluorogen which reacts with unreacted thiol groups; and (c) measuring the resultant intensity of light or fluorescence of the chromogen or fluorogen.
Claim 3
Dependent Claim
16 words
A method of claim 1, wherein a mercaptoalkanol is used as the reagent containing thiol groups.
Claim 4
Dependent Claim
10 words
A method of claim 2, wherein the mercaptoalkanol is mercaptoethanol.
Claim 5
Dependent Claim
13 words
A method of claim 1, wherein 2,2'-dinitro-5,5'-dithiodibenzoic acid is used as the chromogen.
Claim 6
Dependent Claim
13 words
A method of claim 2, wherein 2,2'-dinitro-5,5'-dithiodibenzoic acid is used as the chromogen.
Claim 7
Dependent Claim
14 words
A method of claim 1, wherein the protein is an antibody or antibody fragment.
Claim 8
Dependent Claim
12 words
A method of claim 1, wherein the measuring step is performed photometrically.
Claim 9
Dependent Claim
14 words
A method of claim 7, wherein the measuring step is performed at 436 nm.
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) | 1995-07-21 | 1996-01-20 | 1996-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-21 | 2000-01-20 | 2000-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-21 | 2004-01-20 | 2004-07-21 | $7700.00 | Window Closed / Lapsed |