A degradable nano-preservative film with photodynamic bactericidal activity and a preparation method therefor, and belongs to the technical field of antibacterial preservative films is provided. The present invention synthesizes nanoparticles with aggregation-induced emission characteristic by self-assembly of berberine that is a natural plant antibacterial component and citric acid. Under white light, the nanoparticles can generate a large amount of reactive oxygen species (ROS), thereby exhibiting efficient and durable antibacterial activity. Nanoparticles are prepared by adding the nanoparticles as a filler to a film-mixed solution composed of sodium alginate, pullulan and egg white. With photodynamic bactericidal activity, the present invention improves over current antibacterial preservative films having short lasting effect and which require direct contact to realize bactericidal effect.

There is provided inter alia a process for drying an isolated polysaccharide comprising the step of spray drying a liquid composition comprising the isolated polysaccharide.

A method of preparing a hydrogel product including crosslinked glycosaminoglycan molecules, said method including: i) providing a glycosaminoglycan crosslinked by amide bonds, wherein the crosslinked glycosaminoglycans include residual amine groups; and ii) acylating residual amine groups of the crosslinked glycosaminoglycans provided in i) to form acylated crosslinked glycosaminoglycans.

A host of new silk material formats are disclosed, all prepared from an initial liquid composition including both silk fibroin and xanthan gum. In some cases, particularly preferred material properties are achieved by the addition of glycerol. These various formats include liquids, whipped silk creams, silk meringues, and compressed/heat-compressed meringues. Among the useful end-uses for these materials is a silk leather, which mimics the feel of conventional leather. Other uses include thermal insulation, absorption/gas sensing, biological scaffolding, and the like. A material that has material properties unexpectedly similar to mycelium is also disclosed.

The present invention relates to the use of an amine compound comprising at least one, preferably at least two amine functions, wherein the amine functions are primary or secondary amines, to reduce the level of furfural and/or hydroxymethylfurfural in a carbohydrate-based binder or binder composition and/or escaping in the course of preparation, cross-linking and/or curing of carbohydrate-based binders. Preferably, the carbohydrate-based binder is obtained from a carbohydrate-based binder composition comprising a carbohydrate component and a cross-linker and possibly reaction product of carbohydrate component and cross-linker, wherein the cross-linker is selected from ammonium salts of inorganic acid, carboxylic acids, salts, ester or anhydride derivatives thereof, and/or combinations thereof.

An aqueous fluid, possibly a wellbore fracturing fluid, comprises an aqueous solution or dispersion of a first polymer, which may be polysaccharide, as a thickener and a cross linking agent to enhance the viscosity of the fluid by crosslinking the first polymer, wherein the crosslinking agent is a second polymer comprising at least one polymer chain with phenyl boronate groups distributed along the polymer chain and the phenyl boronic acid groups have nitrogen attached to the phenyl group at a position which is meta relative to the boronate group.

A process is disclosed herein comprising the steps: a) contacting an esterifying agent and a polysaccharide in the presence of a first solvent and suitable reaction conditions for a reaction time sufficient to form a product comprising a polysaccharide ester composition, the polysaccharide ester composition comprising a polysaccharide ester having a degree of substitution of about 0.001 to about 3; wherein the esterifying agent comprises an acyl halide, a phosphoryl halide, a carboxylic acid anhydride, a haloformic acid ester, a carbonic acid ester, or a vinyl ester; and the ratio of esterifying agent to polysaccharide is in the range of about 0.001:1 to about 3:1 on a molar equivalent basis; b) combining the product obtained in step a) with polyacrylonitrile; and c) spinning fibers.

The present invention includes a hydrogel and a method of making a porous hydrogel by preparing an aqueous mixture of an uncrosslinked polymer and a crystallizable molecule; casting the mixture into a vessel; allowing the cast mixture to dry to form an amorphous hydrogel film; seeding the cast mixture with a seed crystal of the crystallizable molecule; growing the crystallizable molecule into a crystal structure within the uncrosslinked polymer; crosslinking the polymer around the crystal structure under conditions in which the crystal structure within the crosslinked polymer is maintained; and dissolving the crystals within the crosslinked polymer to form the porous hydrogel.

A purified and sterilized polysaccharide that exhibits enhanced and extended shelf life over conventionally prepared polysaccharides for biomedical applications. The polysaccharide, upon crosslinking, forms a hydrogel that functions as a protective coating or on tissue and structures in the ears, nose, throat, limbs and spinal column.

The present invention provides a temperature sensitive hydrogel composition including a nucleic acid and chitosan. Since the hydrogel has excellent biocompatibility and biostability, and simultaneously has sol-gel phase transition properties depending on temperature changes, the hydrogel is present in a sol state at room temperature and becomes a gel when the hydrogel is injected into the human body or applied on the surface of epithelial skin and the temperature increases. Thus, the temperature-sensitive hydrogel of the present invention can be directly injected into and applied on certain parts requiring treatment and the retention and attaching time of a drug is increased through gelation depending on the temperature so that drug efficacy is sufficiently exhibited. Therefore, it is expected that the temperature-sensitive hydrogel of the present invention can be utilized for various treatments.