A method for preparing non-free radical photo-crosslinked hydrogels includes: dissolving component A that is a polymer derivative modified with o-nitrobenzyl phototrigger in a biocompatible medium to obtain solution A; dissolving component B that is a polymer derivative containing hydrazide, hydroxylamine or primary amine in a biocompatible medium to obtain solution B; mixing solution A and solution B to obtain a precursor solution of hydrogel; under light irradiation, crosslinking aldehyde generated from the o-nitrobenzyl with the hydrazine, hydroxylamine or primary amine to obtain a hydrogel by forming hydrazone, oxime or schiff base, respectively. A kit for preparation and application of the hydrogel in tissue repair, beauty therapy, and cells, proteins or drugs carriers is also described. The method or kit can achieve in situ photo-gelling on tissue surface or in situ forming thin gel on wounds in clinical treatment of wounds.

Enzymatically degradable compositions containing biocompatible polymers reactive with glycosaminoglycan compositions having a first glycosaminoglycan compound having a first degree of acetylation and a second glycosaminoglycan compound having a second degree acetylation different than the first degree of acetylation.

A composition and method of preparing the composition for rapid and effective hemostasis is provided. The composition includes a first agent to induce platelet plug formation, a second to induce vasoconstriction and a third agent for activation of coagulation cascade. The composition comprises of 0.01% to 5% of chitosan; 0.01% to 0.25% of potassium aluminum sulphate; and 0.01% to 0.25% calcium salt. The clotting time of the composition is in the range of 30s to 140s. A method of preparing the hemostatic composition is further disclosed. The composition is configured to control hemorrhage from oozing and pressured bleeding injury any site in human/animal body.

A method for at least partial deacetylation of a biopolymer comprising acetyl groups, including: a1) providing a biopolymer including acetyl groups; a2) reacting the biopolymer including acetyl groups with hydroxylamine (NH.sub.2OH) or a salt thereof at a temperature of 100° C. or less for 2-200 hours to form an at least partially deacetylated biopolymer; and a3) recovering the at least partially deacetylated biopolymer.

The composition, advantageously an emulsion or a foam, includes an internal phase dispersed in a hydrophilic continuous phase, the percentage of the internal phase being higher than 50%. The emulsion composition contains nanocrystals of a polysaccharide other than cellulose, advantageously chitin, that are located at the interface between the internal phase and the hydrophilic continuous phase.

The invention relates to a method of preparing a composition, the composition comprising a crosslinked first polymer, optionally a second polymer, which may be crosslinked or non-crosslinked, and water, wherein the first and the second polymer are selected from a polysaccharide, comprising at least steps (i) to (iv): (i) crosslinking a mixture comprising the first polymer and water; (ii) subsequent to the crosslinking in step (i), terminating the crosslinking; (iii) optionally blending the product obtained in step (ii) with the second polymer; (iv) subjecting the product obtained in step (iii) to dialysis.

Disclosed are micronized hydrophilic systems of highly concentrated, cross-linked biopolymers. The system is created by combining a biopolymer with a cross-linking agent under mechanical kneading and allowing the biopolymer to undergo a cross-linking process followed by purification, drying and milling. The resulting micronized biopolymer system has an increased biopolymer concentration and increased longevity within the body.

The present invention relates to a method for crosslinking hyaluronic acid, a method for preparing an injectable hydrogel, the hydrogel thus obtained and its use.

A material with high oxygen permeability based on marine biological substance is disclosed. The material is obtained by compounding a silicon-containing substance with a silicon-oxy group and a bioactive substance selected from one or more of alginic acid, collagen, hyaluronic acid and a salt thereof, in the presence of a crosslinking agent. Also disclosed is a preparation method for the material including: mixing the silicon-containing substance and bioactive substance under acidic condition, and then crosslinking the mixture in the presence of a crosslinking agent. Also disclosed is a use of the material with high oxygen permeability or method thereof to prepare a corneal contact lens, corneal scaffold material, or corneal substitute. The material can satisfy the requirement of high oxygen permeability for extended wear and shows good wearing comfort. The material is biocompatible and has high safety performance.

Reversibly crosslinkable polymeric networks, including reversibly crosslinkable hydrogel networks are provided. Also provided are methods of making the polymeric networks and methods of using the hydrogel networks in tissue engineering applications. The reversibly crosslinkable polymeric networks are composed of polymer chains that are covalently crosslinked by azobenzene boronic ester bonds that can be reversibly formed and broken by exposing the polymeric networks to different wavelengths of light.