GB2151244A
Expired / Lapsed
GB
⏱️ 0.0 years remaining
Insolubilized biocompatible hyaluronic acid preparations
Assignee: Biomatrix Inc
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Filing: 1984-08-13
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Granted: —
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Expires: 2004-08-13
Abstract
Abstract Water insoluble, biocompatible hyaluronic acid preparations are made by subjecting hyaluronic acid to treatment with a cross-linking agent selected from formaldehyde, dimethylolurea, dimethylolethylene urea, ethylene oxide, a polyaziridine, a polyisocyanate and divinyl sulphone. The preparations may be used in such in vivo applications as in artificial heart valves, vascular grafts etc.
Inventors
- 👤 Endre A Balazs
- 👤 Adolf Leshchiner
Bibliographic Details
Application Number
—
Jurisdiction
GB
Data Source
google_patents
Last Synchronized
2026-10-23 04:11
CPC Classifications
C; C08; C08B; C08B37/00; C08B37/006; C08B37/0063; C08B37/0072
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
44 words
A method of making a water insoluble hyaluronic acid preparation, said method comprising subjecting hyaluronic acid or an acid addition salt thereof to treatment with a cross-linking agent selected from formaldehyde, dimethylol urea, dimethylolethylene urea, ethylene oxide, a polyaziridine, a polyisocyanante and divinyl sulfone.
Claim 2
Independent Claim
44 words
A method of making a water insoluble hyaluronic acid preparation, said method comprising subjecting hyaluronic acid or an acid addition salt thereof to treatment with a cross-linking agent selected from formaldehyde, dimethylol urea, dimethylolethylene urea, ethylene oxide, a polyaziridine, a polyisocyanante and divinyl sulfone.
Claim 3
Dependent Claim
23 words
A method according to Claim 1, wherein said hyaluronic acid, or salt thereof, is in the form of a powder, film or gel.
Claim 4
Dependent Claim
26 words
A method according to Claim 1 or Claim 2, wherein the cross-linking agent is formaldehyde and treatment is effected in an aqueous medium at reflux temperature.
Claim 5
Dependent Claim
26 words
A method according to Claim 1 or Claim 2, wherein the cross-linking agent is a polyaziridine and treatment is effected under dry conditions at ambient temperature.
Claim 6
Dependent Claim
25 words
A method according to Claim 1 or Claim 2, wherein the cross-linking agent is a polyisocyanate and treatment is effected in acetone at reflux temperature.
Claim 7
Dependent Claim
23 words
A method according to Claim 1 or Claim 2, wherein the cross-linking agent is dimethylolethylene urea and treatment is effected at about 1100C.
Claim 8
Dependent Claim
16 words
A method according to Claim 1 or Claim 2, wherein the cross-linking agent is divinyl sulfone.
Claim 9
Dependent Claim
14 words
A method according to Claim 7, wherein the treatment is effected at about 60-65"C.
Claim 10
Dependent Claim
19 words
A method according to Claim 7, wherein the treatment is effected at about 20"C in an aqueous alkaline medium.
Claim 11
Dependent Claim
19 words
A method according to Claim 9, wherein treatment is effected at a pH in excess of about pH 9.
Claim 12
Dependent Claim
16 words
A method according to Claim 9 or Claim 10, wherein treatment is effected for 1-20 hours.
Claim 13
Independent Claim
23 words
A method according to any one of Claims 9-11, wherein the ratio of hyaluronic acid to divinyl sulfone is about 3:1 by weight.
Claim 14
Independent Claim
20 words
A method of making a water insoluble hyaluronic acid preparation, substantially as described in any one of the Examples herein.
Claim 15
Independent Claim
20 words
A method of making a water insoluble hyaluronic acid preparation, substantially as described in any one of the Examples herein.
Claim 16
Dependent Claim
10 words
The product of a method according to any preceding claim.
References Cited (Backward Citations)
No citation records indexed.
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