# US 2020/0399431 A1 · Covalently Cross-Linked Hyaluronic Acid Aerogel, Hydrogel, and Preparation Method Thereof

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- Number: US 2020/0399431 A1
- Document ID: US20200399431A1
- Status: Published application
- Kind: A1
- Application number: 16/977,651
- Filed: 2019-06-21
- Published: 2020-12-24
- Earliest claimed: 2018-06-27
- Assignees: Hunan Elixer Therapeutics Co., Ltd.
- Applicants: Hunan Elixer Therapeutics Co., Ltd.
- Inventors: Yu Huang; Bihuang Hu
- Web page: https://patentgrep.com/patent/US20200399431A1

## CPC

- C08J 3/075: Macromolecular gels
- A61L 24/0031: {Hydrogels or hydrocolloids}
- A61L 24/0036: {Porous materials, e.g. foams or sponges}
- A61L 24/0042: {Materials resorbable by the body}
- A61L 24/08: Polysaccharides {(A61L24/043 takes precedence)}
- A61L 26/0023: {Polysaccharides}
- A61L 26/008: {Hydrogels or hydrocolloids}
- A61L 26/0085: {Porous materials, e.g. foams or sponges}
- A61L 26/009: {Materials resorbable by the body}
- A61L 27/20: Polysaccharides
- A61L 27/52: Hydrogels or hydrocolloids
- A61L 27/56: Porous materials, {e.g. foams or sponges}
- C08J 3/24: Crosslinking, e.g. vulcanising, of macromolecules (mechanical aspects B29C35/00; crosslinking agents C08K)
- C08J 2305/08: Chitin; Chondroitin sulfate; Hyaluronic acid; Derivatives thereof
- C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29)
- A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K)

## Abstract

The present invention relates to a covalently cross-linked hyaluronic acid aerogel, a hydrogel, and a preparation method thereof. The method includes steps of: taking hyaluronic acid as a raw material to prepare a hyaluronic acid aqueous solution; taking 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, or polyethylene glycol diglycidyl ether as a crosslinking agent; promoting a chemical crosslinking through covalent bonds between the crosslinking agent and the hyaluronic acid by a freeze-drying technique to obtain a covalently cross-linked hyaluronic acid aerogel; furthermore, soaking the covalently cross-linked hyaluronic acid aerogel in purified water, which absorbing water and swelling to obtain a covalently cross-linked hyaluronic acid hydrogel. The covalently cross-linked hyaluronic acid aerogel has good liquid absorption properties, and can quickly absorb water and swell to the covalently cross-linked hyaluronic acid hydrogel.

## Claims

### Claim at position 1

1: A preparation method of a covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof, wherein a crosslinking agent is added into a hyaluronic acid aqueous solution to prepare a crosslinking reaction system; the crosslinking reaction system is subjected to crosslinking reaction in a freeze-drying environment immediately to prepare a covalently cross-linked hyaluronic acid aerogel; the obtained covalently cross-linked hyaluronic acid aerogel absorbs water and swells to obtain a covalently cross-linked hyaluronic acid hydrogel.

### Claim at position 2 (depends on 1)

2: The preparation method of a covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof according to claim 1, wherein the crosslinking agent is a diglycidyl ether crosslinking agent.

### Claim at position 3 (depends on 1)

3: The preparation method of a covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof according to claim 1, wherein the diglycidyl ether crosslinking agent is 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether or poly ethylene glycol diglycidyl ether (n=10, molecular weight: 500).

### Claim at position 4 (depends on 1)

4: The preparation method of a covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof according to claim 1, wherein the concentration of the crosslinking agent is 0.1% to 1% (v/v).

### Claim at position 5 (depends on 1)

5: The preparation method of a covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof according to claim 1, wherein the crosslinking reaction system reacts under a neutral condition of pH 6 to 8, preferably about 7.

### Claim at position 6 (depends on 1)

6: The preparation method of a covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof according to claim 1, wherein the molecular weight of hyaluronic acid is 3.5×105 to 1.5×106 Da.

### Claim at position 7 (depends on 1)

7: The preparation method of a covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof according to claim 1, wherein the concentration of the hyaluronic acid aqueous solution is 0.5% to 4% (w/v).

### Claim at position 8 (depends on 1)

8: A covalently cross-linked hyaluronic acid aerogel and a hydrogel thereof prepared by the method according to claim 1.

### Claim at position 9 (depends on 7)

9: A use of the covalently cross-linked hyaluronic acid aerogel and the hydrogel thereof according to claim 7 in cell engineering, tissue engineering, drug carriers or cosmetic surgery.

### Claim at position 10 (depends on 9)

10: The use according to claim 9, wherein as surgical sealant and adhesive or wound dressing to promote wound healing.