The invention provides hydrogel, wherein the hydrogel has a supramolecular cross-linked network obtainable or obtained from the complexation of an aqueous composition including a host, such as cucurbituril, and one or more polymers having suitable guest functionality. One or more polymers in the aqueous composition may have a molecular weight of 50 kDa or more, such as 200 kDa or more. The hydrogel may hold a component, such as a therapeutic compound or a biological molecule. The hydrogels are suitable for use in medicine.

The invention relates to the chitosan polymer derivatives of formula I: and pharmaceutically acceptable salts and esters thereof, wherein Y, X.sup.1, X.sup.4, R.sup.1, R.sup.2, and n are defined in the detailed description and claims. The chitosan polymer derivatives of formula I bind to or associate with alpha-4-beta-1 (α4β1) and alpha-V-beta-3 (α Vβ3) integrin dimers and can be used in delivery formulations to deliver drugs, nucleic acids, or other therapeutic compounds to tissues or cells expressing such integrins. ##STR00001##

The invention relates to a hydrogel product comprising glycosaminoglycan molecules as the swellable polymer, wherein the glycosaminoglycan molecules are covalently crosslinked via crosslinks comprising a spacer group selected from the group consisting of di-, tri-, tetra-, and oligosaccharides.

The present invention relates to the use of a methacrylate or acrylate modified polysaccharide; or a single-chain polysaccharide methacrylate or acrylate-based nanoparticle, having a surface tension measured by Du Noüy Ring method equal to or lower than 63 mN/m, as oil-in-water emulsion stabilizer; and an oil-in-water emulsion stabilizer composition, and an oil-in-water emulsion containing them. It also relates to processes for their preparation, and their uses.

The present invention is directed to a new cross-linked chitosan, preparations, compositions and uses thereof. In particular, the invention relates to nanoparticles and compositions thereof useful as active agents and delivery systems for at least one bioactive agent.

The invention discloses a thiolated chitosan and a preparation method thereof, which is chitosan co-modified by hydroxybutyl and sulfhydryl. The preparation method includes the following steps: firstly, hydroxybutyl is introduced into a chitosan molecular chain, and then sulfhydryl is introduced as a sulfhydryl moiety by a condensation reaction between free amino of hydroxybutyl chitosan and carboxyl of L-cysteine. An aqueous solution of the thiolated chitosan of the invention is in a solution state at low temperature, and can be flow-injected. When the temperature rises to around 37° C., a hydrogel can be formed. Due to the introduction of sulfhydryl, the antioxidant ability and tissue adhesion ability of the material are increased. The thiolated chitosan prepared according to the method may have wide application prospects in an aspect such as tissue engineering, drug delivery systems, cell culture, cosmetics, etc.

The present invention relates to a process for producing a low endotoxin alkali chitosan, and also to a process for producing low endotoxin neutral chitosan, chitosan salt and chitosan derivatives, and to the products of such processes. The process comprises contacting chitosan with an alkali solution to form a mixture and leaving the mixture for at least about 12 hours. The low endotoxin alkali chitosan may be used in the manufacture of other useful chitosan based products.

The present invention encompasses methods and compositions for generating a biomimetic proteoglycan. The invention includes methods of treating a disease, disorder, or condition of soft tissue using a biomimetic proteoglycan.

The present invention relates to a process for the preparation of pharmaceutical, injectable or ophthalmic grade hyaluronic acid, or a salt thereof, for use in the dermocosmetic or pharmaceutical field or in medical devices, which comprises dissolution of hyaluronic acid or a salt thereof in organic solvent, a heat cycle, and recovery of the product by precipitation and successive washes in organic solvents.

Provided are: a hyaluronic acid derivative composition that comprises (A) a hyaluronic acid derivative having a steryl group introduced therein; and (B) a polar group-containing compound having at least one functional group selected from the group consisting of hydroxy group, carboxy group, amino group, amide group, carbamate group, urea group and thiol group, wherein the steryl group has been introduced at a ratio of 0.1% or more and less than 35% relative to the hyaluronic acid derivative (A); a pharmaceutical composition that contains the hyaluronic acid derivative composition as a carrier; and a hyaluronic acid derivative-drug conjugate composition wherein, in the hyaluronic acid derivative composition, one or more drugs are conjugated to the hyaluronic acid derivative (A).