EP0239335A2
Expired / Lapsed
EP
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Non-inflammatory hyaluronic acid fraction and process for preparing it
Assignee: INTERNATIONAL PHARMACEUTICAL PRODUCTS Inc
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Filing: 1987-03-20
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Granted: —
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Expires: 2007-03-20
Abstract
Abstract A sterile, non-inflammatory, heat-resistant hyaluronic acid fraction of low molecular weight, and a method for extracting it from a crude source. The hyaluronic acid fraction is obtained by washing a deproteinized crude source with butanol, precipitating a hyaluronic acid-quaternaryalkylamine complex, dissolving the complex in an excess of sodium dodecylsulfate solution, and precipitating the sterile, non-inflammatory, heat-resistant hyaluronic acid fraction from the soution.
Inventors
- 👤 Jean C/O International Pharmaceutical Hildesheim
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 11:14
CPC Classifications
C; C07; C07H; C07H1/00; C07H1/06; C08; C08B; C08B37/00; C08B37/006; C08B37/0063; C08B37/0072; C08B37/0006; C08B37/0024; C08B37/0027; C08B37/003
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
98 words
A process for preparing a sterile, non-inflammatory, heat-resistant hyaluronic acid fraction which comprises precipitating hyaluronic acid from a crude source, denucleidizing and deproteinizing the precipitated hyaluronic acid, washing the denucleidized and deproteinized hyaluronic acid with a quaternaryalkyl or aryl amine by forming a hyaluronic acid-quaternaryalkyl or aryl amine complex, dissolving the hyaluronic acid-quaternaryalkyl or aryl amine complex with an excess of sodium dodecylsulfate and thereby releasing the hyaluronic acid into the sodium dodecylsulfate solution free of the quaternaryalkyl or aryl amine, and precipitating the freed hyaluronic acid to yield a sterile, pyrogen-free, protein-free, non-inflammatory, heat-resistant hyaluronic acid fraction.
Claim 2
Dependent Claim
98 words
A process for preparing a sterile, non-inflammatory, heat-resistant hyaluronic acid fraction which comprises precipitating hyaluronic acid from a crude source, denucleidizing and deproteinizing the precipitated hyaluronic acid, washing the denucleidized and deproteinized hyaluronic acid with a quaternaryalkyl or aryl amine by forming a hyaluronic acid-quaternaryalkyl or aryl amine complex, dissolving the hyaluronic acid-quaternaryalkyl or aryl amine complex with an excess of sodium dodecylsulfate and thereby releasing the hyaluronic acid into the sodium dodecylsulfate solution free of the quaternaryalkyl or aryl amine, and precipitating the freed hyaluronic acid to yield a sterile, pyrogen-free, protein-free, non-inflammatory, heat-resistant hyaluronic acid fraction.
Claim 3
Dependent Claim
17 words
A process according to Claim 1 wherein the quaternary-alkylamine is cetyl pyridinum chloride or 1-hexadecyltrimethyl ammonium bromide.
Claim 4
Dependent Claim
22 words
A process according to Claim 1 or 2 wherein the hyaluronic acid fraction has an average molecular weight of less than 750,000.
Claim 5
Dependent Claim
72 words
A process according to Claim 1, 2 or 3 wherein the hyaluronic acid is denucleidized and deproteinized by dissolving the precipitated hyaluronic acid in a sodium phosphate buffer at pH 7.2 or 7.4, heating the hyaluronic acid suspension to 35-38 degrees C, adding DNase and RNase and incubating until the nucleotides present in the solution are digested, and then added a 1% protease solution and incubating until the protease reaction is complete.
Claim 6
Dependent Claim
21 words
A process according to Claim 4 wherein the sodium phosphate buffer contains a magnesium compound and has a pH of 7.2.
Claim 7
Dependent Claim
21 words
A process according to any one of the preceding claims wherein hyaluronic acid is precipitated from a crude source with ethanol.
Claim 8
Dependent Claim
23 words
A process according to any one of the preceding claims wherein freed hyaluronic acid is precipitated from the sodium dodecylsulfate solution with ethanol.
Claim 9
Dependent Claim
16 words
A sterile, non-inflammatory, heat-resistant hyaluronic acid fraction having an average molecular weight of less than 750,000.
Claim 10
Dependent Claim
16 words
A sterile, non-inflammatory, heat-resistant hyaluronic acid fraction having an average molecular weight of less than 750,000.
Claim 11
Dependent Claim
17 words
A hyaluronic acid fraction according to Claim 8 wherein the average molecular weight is at least 50,000.
Claim 12
Dependent Claim
15 words
The sodium salt of a hyaluronic acid fraction as claimed in Claim 8 or 9.
Claim 13
Dependent Claim
24 words
A composition comprising a hyaluronic acid fraction or salt as claimed in Claim 8, 9 or 10 dissolved in a physiologically acceptable buffer solution.
Claim 14
Dependent Claim
15 words
A composition according to Claim 11 wherein the buffer solution is PBS or physiological saline.
Claim 15
Dependent Claim
20 words
A composition according to Claim 11 or 12 wherein the hyaluronic acid concentration is 1.2 to 2.0 percent by weight.
References Cited (Backward Citations)
No citation records indexed.
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