US5380880A
Expired / Lapsed
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Fluorescent pH indicators
Assignee: Becton Dickinson and Co
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Filing: 1993-12-06
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Granted: 1995-01-10
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Expires: 2013-12-06
Abstract
Abstract Fluorescent pH indicator compounds which exhibit an increase in fluorescence intensity with decreasing pH. The indicators are derivatives of rhodamine and sulforhodamine type dyes and are particularly useful for measuring pH in acidic environments such as carbon dioxide production by microorganisms and pH of certain acidic intracellular compartments.
Inventors
- 👤 J. Bruce Pitner
- 👤 Randal A. Hoke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:19
CPC Classifications
C; C09; C09B; C09B11/00; C09B11/04; C09B11/10; C09B11/24; C07; C07D; C07D311/00; C07D311/02; C07D311/78; C07D311/80; C07D311/82; G; G01; G01N; G01N31/00; G01N31/22; G01N31/221
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
98 words
A method for synthesizing a compound having the structure ##STR4## comprising the steps of: a) reacting sulforhodamine B sulfonyl chloride (SRB) with gamma-amino butyric acid (GABA) in the presence of 4-dimethylaminopyridine and triethylamine to produce an SRB-GABA reaction product; b) reacting the SRB-GABA with N-hydroxy-succinimide (NHS) in the presence of methylene chloride and dicyclohexylcarbodiimide to produce an SRB-GABA NHS ester; c) recovering the SRB-GABA NHS ester; d) reacting the SRB-GABA NHS ester with 12-amino-dodecanoic acid in the presence of methylene chloride to produce a reaction product, and; e) recovering the compound from the reaction product of step d).
Claim 2
Independent Claim
98 words
A method for synthesizing a compound having the structure ##STR4## comprising the steps of: a) reacting sulforhodamine B sulfonyl chloride (SRB) with gamma-amino butyric acid (GABA) in the presence of 4-dimethylaminopyridine and triethylamine to produce an SRB-GABA reaction product; b) reacting the SRB-GABA with N-hydroxy-succinimide (NHS) in the presence of methylene chloride and dicyclohexylcarbodiimide to produce an SRB-GABA NHS ester; c) recovering the SRB-GABA NHS ester; d) reacting the SRB-GABA NHS ester with 12-amino-dodecanoic acid in the presence of methylene chloride to produce a reaction product, and; e) recovering the compound from the reaction product of step d).
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) | 1998-01-09 | 1998-07-11 | 1999-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-09 | 2002-07-11 | 2003-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-09 | 2006-07-11 | 2007-01-10 | $7700.00 | Window Closed / Lapsed |