Patent US5895420A successfully refreshed from Google Patents.
Patent US2688878A successfully refreshed from Google Patents.
US4886787A
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US
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Method of preventing adhesion between body tissues, means for preventing such adhesion, and process for producing said means
Assignee: Pfizer Health AB
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Filing: 1985-07-16
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Granted: 1989-12-12
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Expires: 2005-07-16
Abstract
Abstract The invention is concerned with a method of preventing adhesions or accretions of body tissues inter se by means of employing a degradable gel of a crosslinked carboxyl-containing polysaccharide. The invention also covers a gel product to be used for this purpose, and a process for preparing said product by means of crosslinking with a di- or polyfunctional expoxide at a pH of from 2 to 5.
Inventors
- 👤 Anthony N. de Belder
- 👤 Thomas Malson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:17
CPC Classifications
C; C08; C08L; C08L5/00; C08L5/08; A; A61; A61L; A61L31/00; A61L31/04; A61L31/042; A61L31/14; A61L31/145; C08B; C08B37/00; C08B37/006; C08B37/0063; C08B37/0072
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
26 words
A gel of sodium hyaluronate or hylaluronic acid cross-linked with a di- or polyfunctional expoxide at a pH within the range of from 2 to 5.
Claim 2
Dependent Claim
26 words
A gel of sodium hyaluronate or hylaluronic acid cross-linked with a di- or polyfunctional expoxide at a pH within the range of from 2 to 5.
Claim 3
Dependent Claim
51 words
A process for preparing a gel consisting of a cross-linked carboxyl-containing polysaccharide selected from the group consisting of carboxymethyl dextran, carboxymethyl starch, carboxymethyl cellulose and glucosminoglycans formed by reacting the polysaccharide at a pH of from 2 to 5 with a bi- or polyfunctional epoxide in the presence of an acid.
Claim 4
Dependent Claim
51 words
A process for preparing a gel consisting of a cross-linked carboxyl-containing polysaccharide selected from the group consisting of carboxymethyl dextran, carboxymethyl starch, carboxymethyl cellulose and glucosminoglycans formed by reacting the polysaccharide at a pH of from 2 to 5 with a bi- or polyfunctional epoxide in the presence of an acid.
Claim 5
Dependent Claim
17 words
A process according to claim 2 wherein said pH is in the range of 2.5 to 4.5.
Claim 6
Dependent Claim
25 words
The process according to claim 2 in which said acid is selected from the group consisting of inorganic acids, organic acids and hydrogen salts thereof.
Claim 7
Dependent Claim
28 words
A process according to claim 2 in which said acid is selected from the group consisting of hydrochloric, sulfuric, nitric or phosphoric acid, or a hydrogen salt thereof.
Claim 8
Dependent Claim
43 words
A process according to claim 2 in which said acid is selected from among (a) lower aliphatic mono- or polycarboxylic acids or (b) aromatic mono- or polycarboxylic acids and sulfonic acids, or (c) hydrogen salts of acids belonging to group (a) or (b).
Claim 9
Dependent Claim
28 words
A process according to claim 2 in which said acid is selected from the group consisting of formic, acetic, propionic, lactic, trichloroacetic, succinic, benzoic, salicylic and p-toluene sulfonic.
Claim 10
Dependent Claim
12 words
A process according to claim 2 wherein said polysaccharide is hyaluronic acid.
Claim 11
Dependent Claim
12 words
A process according to claim 2 wherein said polysaccharide is sodium hyaluronate.
Claim 12
Dependent Claim
12 words
A process according to claim 4 wherein said polysaccharide is sodium hyaluronate.
Claim 13
Dependent Claim
12 words
A process according to claim 5 wherein said polysaccharide is sodium hyaluronate.
Claim 14
Independent Claim
74 words
A method of preventing adhesions or accretions of body tissues in which one or more pieces of a gel of a crosslinked carboxylgroup-containing polysaccharide selected from the group consisting of carboxymethyl dextran, carboxymethyl starch, carboxymethyl cellulose and glucosaminoglycans, during the course of a surgical operation, is introduced into the interstices between the tissues to be maintained in a separated condition; the gel being formed by reacting said polysaccharide with a bi- or polyfunctional epoxide.
Claim 15
Independent Claim
74 words
A method of preventing adhesions or accretions of body tissues in which one or more pieces of a gel of a crosslinked carboxylgroup-containing polysaccharide selected from the group consisting of carboxymethyl dextran, carboxymethyl starch, carboxymethyl cellulose and glucosaminoglycans, during the course of a surgical operation, is introduced into the interstices between the tissues to be maintained in a separated condition; the gel being formed by reacting said polysaccharide with a bi- or polyfunctional epoxide.
Claim 16
Dependent Claim
32 words
A method according to claim 12 wherein the gel is form®d by reacting the polysaccharide with a bi- or polyfunctional epoxide at a pH within the range of from 2 to 5.
Claim 17
Dependent Claim
14 words
A method according to claim 13 wherein said pH is from 2.5 to 4.5.
Claim 18
Dependent Claim
12 words
A method according to claim 12 wherein said polysaccharide is sodium hyaluronate.
Claim 19
Dependent Claim
12 words
A method according to claim 13 wherein said polysaccaride is sodium hyaluronate.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-11 | 1993-06-12 | 1993-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-11 | 1997-06-12 | 1997-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-11 | 2001-06-12 | 2001-12-12 | $7700.00 | Window Closed / Lapsed |