EP0268421A2
Expired / Lapsed
EP
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An implant composition and a method of preparing the same
Assignee: Koken Co Ltd
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Filing: 1987-11-11
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Granted: —
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Expires: 2007-11-11
Abstract
Abstract An implant composition comprising an aqueous dispersion of atelocollagen crosslinked with hexamethylene diisocyanate has a high degree of volume retention and low immunogenicity in a living body, and is not cytotoxic.
Inventors
- 👤 Tsuyoshi Koken Co. Ltd. Yahagi
- 👤 Teruo Koken Co. Ltd. Miyata
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 13:33
CPC Classifications
C; C08; C08H; C08H1/00; C08H1/06; A; A61; A61L; A61L27/00; A61L27/14; A61L27/22; A61L27/24; A61F; A61F2310/00; A61F2310/00005; A61F2310/00365
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
30 words
An implant composition comprising an aqueous dispersion of atelocollagen equilibrated with biological conditions by a buffer solution, 60 to 100 weight % of the atelocollagen being crosslinked with hexamethylene diisocyanate.
Claim 2
Dependent Claim
30 words
An implant composition comprising an aqueous dispersion of atelocollagen equilibrated with biological conditions by a buffer solution, 60 to 100 weight % of the atelocollagen being crosslinked with hexamethylene diisocyanate.
Claim 3
Dependent Claim
26 words
An implant composition according to claim 1, in which the amount of total atelocollagen in said dispersion is in the range of 25 to 100 mg/ml.
Claim 4
Dependent Claim
26 words
An implant composition according to claim 1 or 2, in which the particle size of crosslinked atelocollagen is in the range of 50 to 200 µm.
Claim 5
Independent Claim
161 words
A method of preparing an implant composition which comprises an aqueous dispersion of atelocollagen equilibrated with biological conditions by a buffer solution, 60 to 100 weight % of said atelocollagen being crosslinked with hexamethylene diisocycanate, comprising (a) dehydrating the aqueous solution of atelocollagen to give an aqueous dispersion containing regenerated atelocollagen fibers; (b) dehydrating the aqueous dispersion by displacing water with alcohol to give an alcoholic dispersion containing regenerated atelocollagen fibers; (c) crosslinking the regenerated atelocollagen fibers in the alcoholic dispersion with hexamethylene diisocyanate; (d) removing unreacted hexamethylene diisocyanate by washing the alcoholic dispersion with a large amount of alcohol; and (e) displacing alcohol in the alcoholic dispersion with water to give an aqueous dispersion, then adding an aqueous solution of uncrosslinked atelocollagen in such an amount that the proportion of uncrosslinked atelocollagen in the amount of total atelocollagen will be less than 40 weight %, and subsequently equilibrating the resultant dispersion with biological conditions by addition of a buffer solution.
Claim 6
Independent Claim
161 words
A method of preparing an implant composition which comprises an aqueous dispersion of atelocollagen equilibrated with biological conditions by a buffer solution, 60 to 100 weight % of said atelocollagen being crosslinked with hexamethylene diisocycanate, comprising (a) dehydrating the aqueous solution of atelocollagen to give an aqueous dispersion containing regenerated atelocollagen fibers; (b) dehydrating the aqueous dispersion by displacing water with alcohol to give an alcoholic dispersion containing regenerated atelocollagen fibers; (c) crosslinking the regenerated atelocollagen fibers in the alcoholic dispersion with hexamethylene diisocyanate; (d) removing unreacted hexamethylene diisocyanate by washing the alcoholic dispersion with a large amount of alcohol; and (e) displacing alcohol in the alcoholic dispersion with water to give an aqueous dispersion, then adding an aqueous solution of uncrosslinked atelocollagen in such an amount that the proportion of uncrosslinked atelocollagen in the amount of total atelocollagen will be less than 40 weight %, and subsequently equilibrating the resultant dispersion with biological conditions by addition of a buffer solution.
Claim 7
Dependent Claim
30 words
A method according to claim 4, in which the amount of total atelocollagen in the aqueous dispersion equilibrated with biological conditions is in the range of 25 to 100 mg/ml.
Claim 8
Dependent Claim
25 words
A method according to claim 4 or 5, in which the particle size of crosslinked atelocollagen is in the range of 50 to 200 µm.
References Cited (Backward Citations)
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