12058 results about "Anti bacterial" patented technology

To provide a timber antiseptic agent which exhibits superior safety and superior antibacterial performance with low influence on the human body and environment.SOLUTION: The present invention relates to a timber antiseptic agent containing an alkyl 4-hydroxybenzoate represented by formula (1) [where R represents an alkyl group having 5 to 10 carbon atoms] or a salt thereof.SELECTED DRAWING: None

The invention discloses an absorbable suture line for surgical suture and a preparation method thereof, and relates to the technical field of medical materials. The absorbable suture line for surgical suture is prepared from the following raw materials in parts by weight: 50 to 65 parts of polylactic acid, 15 to 20 parts of polyglycolic acid, 3 to 5 parts of sodium carboxymethyl cellulose, 3 to 8 parts of a toughening agent, 3 to 6 parts of an antibacterial agent, 0.3 to 0.8 part of a lubricating agent, 1 to 2 parts of sodium hyaluronate and 5 to 10 parts of polyvinyl alcohol. The toughening agent is obtained by reacting hydroxyethyl acrylate with ethylenediamine to generate a four-arm compound and then reacting with 6-caprolactone and DL-lactide. The absorbable suture line for surgical suture prepared by the invention has excellent tensile property and antibacterial property, and can meet the application requirements of clinical medical treatment.

The invention provides a bio-based adhesive and a preparation method thereof. Inspired by a spider thread structure, biomass adhesive interface enhancement based on a tannic acid adhesion group is combined with construction of a differential phase separation structure by biomass-induced polylipoic acid depolymerization, and a brand new strategy of adhesion-cohesion synergistic enhancement of the adhesive strength of the adhesive is realized. According to the invention, tannic acid and carboxymethyl chitosan are introduced into a lipoic acid-based adhesive, so that the purpose of synergistically enhancing the bonding performance of the adhesive through adhesion-cohesion is achieved, and the defects of weak cohesion, low bonding strength, poor water resistance, poor moisture resistance and the like of the conventional biomass adhesive are overcome. Benefited from a new strategy of adhesion-cohesion synergistic enhancement, the biomass adhesive has good adhesive strength in various environments and materials. In addition, the biomass adhesive also has the characteristics of biological safety, antibacterial and mildew-proof properties and recoverability, so that the product has wider application and potential compared with the previous product, and has a good application prospect.

The invention discloses bone cement for orthopedic repair and a preparation method thereof, and relates to the technical field of bone cement. The bone cement for orthopedic repair comprises solid-phase powder and a liquid-phase component, the solid-phase powder comprises the following components in parts by weight: 55-65 parts of composite calcium phosphate, 10-15 parts of bioactive glass, 2-3 parts of a developing agent, 1-2 parts of hydroxyapatite, 8-12 parts of a modified toughening agent and 2-3 parts of nano cellulose fibers; the liquid phase component is prepared from the following components in parts by weight: 40 to 50 parts of a sodium alginate solution, 10 to 20 parts of methacrylated gelatin, 0.5 to 1 part of transglutaminase, 30 to 60 parts of a citric acid buffer solution and 1 to 2 parts of an antibacterial agent. The preparation method comprises the following steps: reacting pentaerythritol with 12-oxododecanoic acid to obtain an intermediate 1, and reacting the intermediate 1 with dopamine to prepare the modified toughening agent. The bone cement for orthopedic repair prepared by the invention has good mechanical, self-repairing and antibacterial properties.

The invention belongs to antibacterial materials, and particularly relates to antibacterial modified waterborne polyurethane and a preparation method and application thereof.The preparation method of the antibacterial modified waterborne polyurethane comprises the following steps that polyol and diisocyanate are mixed and subjected to a prepolymerization reaction, and a polyurethane prepolymer is obtained; mixing the polyurethane prepolymer and a chain extender, and carrying out chain extension reaction; in the chain extension reaction, adding the graft and carrying out esterification reaction to obtain a first intermediate; mixing the first intermediate with triethylamine and carrying out neutralization reaction to obtain a second intermediate; and emulsifying the second intermediate in deionized water to obtain the antibacterial modified waterborne polyurethane. Compared with the prior art, the antibacterial waterborne polyurethane has the advantages that the problems of poor intermiscibility, low durability and the like in physical addition and the problems of limited binding objects and weak antibacterial effect in covalent binding in the antibacterial waterborne polyurethane in the prior art are solved. According to the scheme, arginine and chitosan are grafted to a molecular chain of waterborne polyurethane, so that the waterborne polyurethane is endowed with a synergistic antibacterial property.

The invention discloses a bamboo powder-containing biodegradable plastic for food contact and a preparation method thereof, and relates to the technical field of bio-based materials. The bamboo powder-containing biodegradable plastic for food contact comprises chitosan starch and modified bamboo powder, the chitosan starch is prepared by adding composite chitosan and amino-terminated polyethylene glycol into oxidized corn starch, and the composite chitosan is prepared by grafting chlorogenic acid on the surface of chitosan and then coating succinic anhydride derivatives. The succinic anhydride derivative is prepared from dodecenyl succinic anhydride and 1, 4-butanediamine through a reaction, so that the plastic has the antibacterial property, and meanwhile, the mechanical property is enhanced; the modified bamboo powder is prepared by reacting bamboo powder with a carboxyl-terminated composition, and the carboxyl-terminated composition comprises carboxyl-terminated polylactic acid and carboxyl-terminated polyamide. The toughness of the plastic is enhanced, and the mechanical property of the plastic is further enhanced.

The invention belongs to the technical field of genetic engineering, and particularly relates to an antibacterial peptide with antibacterial and antiviral effects and application and a product thereof. The amino acid sequence of the antibacterial peptide provided by the invention has the following general formula: X1GX2FX3FX4KKFX5LFX6X7SKVLK, x1 is M or has no amino acid; x2 is one of R, G and H; x3 is one of KS, KR, HR and HH; x4 is R or L; x5 is one of KK, HH and HK; x6 is RR or KK; and X7 is I or L. The antibacterial peptide disclosed by the invention has a relatively good antibacterial effect, and shows antiviral activity on HPV16 (Human Papilloma Virus 16) and HPV18 (Human Papilloma Virus 18). Good application prospects are shown in the preparation of antibacterial or antiviral products.

The invention relates to the technical field of film material preparation, and discloses a polylactic acid antibacterial packaging film and a preparation method thereof, the polylactic acid antibacterial packaging film comprises the following raw material components by weight: 60-80 parts of polylactic acid, 10-20 parts of polyvinyl alcohol, 10-20 parts of nano zinc oxide, 0.5-1.5 parts of nano cellulose, 1-3 parts of an antibacterial agent, and 10-15 parts of corn starch; the antibacterial agent is prepared from the following components in parts by weight: 5-10 parts of carboxymethylated chitosan and 0.5-2 parts of a dynamic disulfide bond cross-linking agent, the substitution degree of the carboxymethylated chitosan is greater than or equal to 80%, the antibacterial agent is prepared from tea tree essential oil and eugenol, and the dynamic disulfide bond cross-linking agent is bis (3-aminopropyl) disulfide. By adopting a composite system of carboxymethylated chitosan and a dynamic disulfide bond cross-linking agent, the technical effects of humidity-triggered self-repairing and mechanical property synergistic improvement are achieved, and compared with a packaging film with a single polymer base material in the prior art, the problem of antibacterial failure caused by mechanical damage is solved.

The invention provides an intelligent evaluation method and system for the antibacterial effect of a water matrix standard substance, and relates to the technical field of intelligent evaluation, and the method comprises the following steps: preparing a bacterial suspension in a logarithmic phase and checking turbidity; preparing a water matrix standard substance and a control solvent, and obtaining a baseline parameter set; setting inoculum size and incubation conditions, determining the antibacterial efficiency in parallel, and performing image segmentation correction on sticky colonies to obtain an original observation set; establishing a deviation transfer relationship, correcting the original data, and forming an endpoint quantization set; and the bacteriostatic validity is output through evidence fusion, and a supplementary experiment is carried out on a critical condition. According to the method, the accuracy and reliability of bacteriostatic effect evaluation of the water matrix standard substance are improved.

The present invention uses commercially available 3-aminopropylsilane coupling agent, diallylamino polyether acrylate, and an alkylating agent, or γ-propanesultone, or γ-butyrolactone as raw materials, and through an aza-Michael addition reaction and a quaternization reaction, a multifunctional silane coupling agent containing one or more quaternary ammonium cations, or sulfobetaine, or carboxybetaine in its molecular structure is prepared, which is used for the surface modification of bioactive glass, and the bioactivity, antibacterial and antifungal properties, and hydrophilicity enhancement effects after the surface modification of bioactive glass are obtained.

The invention discloses a Janus wound dressing with antibacterial and tissue repair promoting functions and a preparation method of the Janus wound dressing, belongs to the technical field of wound dressings, and aims to realize antibacterial, tissue repair promoting and moist wound healing microenvironment through freeze drying and electrostatic spinning technologies. Polycaprolactone (PCL), bioactive glass (BG) and curcumin Cur are used for preparing a hydrophobic inner layer capable of promoting tissue repair, methacrylated gelatin GelMA is used for preparing a hydrophilic outer layer with moisturizing performance, and the PCL-BG-Cur / GelMA composite wound dressing with antibacterial, moisturizing and repair promoting functions is constructed. Animal experiment results show that the dressing loaded with curcumin Cur and bioactive glass BG has multiple functions of synergistic antibiosis, moisturizing and the like, the result shows that the prepared dressing has the performance of promoting epithelization, collagen deposition, new hair follicle formation and the like, and the dressing has a considerable application prospect in the aspect of rapid wound repair.

The invention relates to the technical field of high-barrier composite packaging films, and discloses a high-barrier composite packaging film with an antibacterial function, which sequentially comprises a base layer, a nano composite barrier layer, an antibacterial functional layer and an outer protective layer from bottom to top, and the layers are tightly attached through a coated starch-based adhesive. According to the high-barrier composite packaging film with the antibacterial function, the cellulose nanowhiskers have the characteristics of high strength and high modulus and are mixed with the bio-based polylactic acid, so that the tensile strength and tear resistance of the bio-based polylactic acid can be remarkably improved, and the structural stability of the packaging film in the using process is guaranteed; nano titanium dioxide and nano cellulose aerogel are arranged in the nano composite barrier layer, so that the barrier property of the packaging film on oxygen and ultraviolet rays can be enhanced, and the packaging film also has a certain antibacterial effect; in addition, the nanocellulose aerogel has a loose porous structure, so that gas molecules can be effectively prevented from passing through, and the barrier property is further improved.

The invention provides an antibacterial synergy-mineralization regulation difunctional nano material as well as a preparation method and application thereof, and belongs to the technical field of biomedical materials. The preparation method comprises the following steps: mixing a disodium hydrogen phosphate solution and a calcium chloride solution to obtain an amorphous calcium phosphate suspension; mixing the amorphous calcium phosphate suspension with a tannic acid solution to obtain an ACP-TA suspension; and finally, mixing the ACP (at) TA suspension and the hydroxypropyl trimethyl ammonium chloride chitosan solution to obtain the bifunctional nano material. A cross-linked shell is formed through the electrostatic adsorption effect of tannic acid and hydroxypropyl trimethyl ammonium chloride chitosan of the antibacterial layer, amorphous calcium phosphate is effectively wrapped, the crystallization process of amorphous calcium phosphate can be remarkably delayed, long-acting release of calcium and phosphorus ions is ensured, the antibacterial function can be effectively achieved, and the service life of the coating is prolonged. An ideal local microenvironment is provided for remineralization of tooth hard tissue, and finally biomimetic mineralization of enamel and deep mineralization plugging of dentinal tubules are achieved.

The invention relates to a preparation method of a high-antibacterial hydrophobic polyamide fiber. The preparation method comprises the following steps: carrying out melt extrusion grafting on polyamide, a quaternary ammonium salt monomer, an initiator and an auxiliary agent to prepare quaternary ammonium salt grafted polyamide; and carrying out melt blending on the prepared quaternary ammonium salt grafted polyamide, polyamide, cuprous oxide and polydimethylsiloxane to obtain the high-antibacterial hydrophobic nylon composite material. And spinning the high-antibacterial hydrophobic nylon composite material to obtain the high-antibacterial hydrophobic polyamide fiber. The high-antibacterial hydrophobic nylon composite material prepared by the method disclosed by the invention can realize efficient antibacterial performance, and the high antibacterial hydrophobic performance of the prepared polyamide fiber is improved.

The invention provides an intelligent response type medical liquid application and a preparation method thereof, and relates to the technical field of medical dressings. The liquid application is composed of a basic repairing component, a natural antibacterial component, a plant active component, an intelligent carrier system and auxiliary materials. Accurate release of active ingredients is realized by adopting a pH / temperature double-response intelligent delivery system, and the transdermal absorption rate is remarkably improved; wound healing is accelerated through the synergistic effect of the compound protein and the plant extract; active ingredients are effectively reserved through a multi-mode sterilization process. The liquid application disclosed by the invention has the characteristics of strong antibacterial property, good environmental adaptability, excellent healing effect and the like.

The invention relates to a same-variety grafting method for Tibetan pinus bungeana, and belongs to the technical field of forest vegetative propagation. In order to solve the technical problems that in the high-altitude environment, the grafting survival rate of the white bark pine is low, a connector is prone to being infected by microorganisms, and callus is formed slowly, efficient grafting is achieved through collaborative optimization of scion pretreatment and stock incision treatment. The method comprises the steps that a one-year-old branch with the diameter being 4-6 mm is selected and subjected to temperature and humidity control and composite antibacterial liquid dipping treatment; a sterile healing interface is formed in cooperation with rootstock incision slope cutting and four times of composite antibacterial liquid brushing; a one-year-old branch is cut, at least two or more bud points exist on the branch, two plump bud points are reserved, the branch is cut open from the position between the two plump bud points, and the scion is obtained. According to the method, the grafting survival rate and the interface stress resistance of the pinus bungeana in the alpine region are remarkably improved, the method is suitable for rapid breeding and hereditary characteristic retention of excellent germplasm of the pinus bungeana in Tibet plateau ecological restoration engineering, and more scion resources of the pinus bungeana can be utilized and protected.

The invention discloses hydrogel loaded with antibacterial polypeptide as well as a preparation method and application of the hydrogel. The preparation method of the hydrogel comprises the steps that antibacterial polypeptide and polyethylene glycol dimethacrylate are subjected to a cross-linking reaction, the hydrogel can be obtained, and the antibacterial polypeptide is obtained through polymerization synthesis of a cationic CBL monomer compound and an HBL monomer compound; the hydrogel has remarkable sterilization and anti-biofilm effects, and in-vitro cytotoxicity shows that the antibacterial polypeptide hydrogel product has no inhibition effect on normal cell growth; when the hydrogel dressing is used as a hydrogel dressing and is combined with novobiocin for use, more than 99% of antibacterial effect is achieved in a diabetes wound infection model and a fungal psoriasis infection model; and when being used as a hydrogel preparation to be combined with fluconazole, the compound has the effect of inhibiting growth of more than 99% of fungi in an animal vaginitis model.

The invention discloses a metal-doped carbon quantum dot as well as preparation and application of the metal-doped carbon quantum dot in a nano antibacterial agent, citric acid, urea and tea polyphenol are taken as precursors, metal salt is added, carbon dot synthesis and metal ion doping are synchronously completed in one step through a hydrothermal method, and the metal-doped carbon quantum dot is prepared; the surfaces of the metal-doped carbon quantum dots are negatively charged, and the metal-doped carbon quantum dots have peroxidase-like activity and catalase-like activity at the same time; the metal ions adopt any one of Fe < 3 + >, Cu < 2 + > and Ce < 3 + >; the metal-doped carbon quantum dots are in a sphere-like shape. The metal-doped carbon quantum dots prepared by the preparation method disclosed by the invention have peroxidase-like activity and catalase-like activity at the same time through precise doping of metal ions, and the two activities have a synergistic effect in an oral periodontitis microenvironment, so that a good antibacterial effect is achieved.

The invention relates to the technical field of antibacterial and antifouling fabrics, provides a preparation method of an antibacterial and antifouling fabric, and solves the problem of poor fabric durability caused by single functional component and lack of physical protection in the prior art. The preparation method comprises the following steps: S1, preparing MOFs loaded antibacterial fibers: blending a metal organic framework antibacterial composite nanomaterial and a polymer matrix material, and carrying out melt spinning to prepare the MOFs loaded antibacterial fibers; s2, constructing a self-cleaning functional coating: dispersing the fluorinated nanoparticles and a polymer adhesive in a solvent to prepare a self-cleaning coating solution; s2, performing surface activation treatment on the MOFs-loaded antibacterial fiber obtained in the step S1, soaking the MOFs-loaded antibacterial fiber in the self-cleaning coating liquid, and performing pulling and curing to form a bionic micro-nano structure coating on the surface of the MOFs-loaded antibacterial fiber so as to obtain a functional composite fiber; s3, spinning forming: taking the functional composite fibers obtained in the step S2 as warp yarns and / or weft yarns, and weaving to obtain the antibacterial and antifouling fabric.

The invention belongs to the technical field of biological medicines, and particularly relates to hydrogel with photo-thermal multiple antibacterial and hemostatic functions. The multifunctional hydrogel is prepared from epsilon-polylysine (EPL), gallic acid (GA), tannic acid (TA) and ferric trichloride hexahydrate. The polyphenols are obtained through multiple mechanisms such as reaction between the polyphenols and amino groups, metal chelation, pi-pi interaction and electrostatic attraction (as shown in Figure 1). The metal ion and multiple dynamic cross-linking system hydrogel is constructed, the hydrogel with positive charges enriched on the surface can act with blood platelets with negative charges, red blood cell aggregation, blood platelet adhesion and vasoconstriction effects are promoted, and the blood coagulation efficiency is improved. The hydrogel shows excellent antibacterial performance and photo-thermal performance, can prevent infection in the inflammation stage of wound healing, can effectively accelerate wound healing, and has good biological safety.

The invention relates to the field of optical lens coatings, and particularly discloses a preparation method of an antifouling and antibacterial spectacle lens coating. The preparation method of the antifouling and antibacterial spectacle lens coating comprises the following steps: depositing a silicon dioxide substrate on the surface of a lens through plasma enhanced chemical vapor deposition treatment; the preparation method comprises the following steps: dispersing nano-graphene and nano-silver particles in an ethanol solvent, adding a silane coupling agent to form a homogeneous suspension, loading the suspension on the surface of a silicon dioxide substrate through a spin-coating method, and carrying out heat treatment curing to form an antibacterial layer, with the loading amount of nano-silver being less than or equal to 0.5 wt%; and etching the surface of the antibacterial layer by adopting a reactive ion etching method, and then grafting perfluorooctyltriethoxysilane on the etched surface at 80-100 DEG C by adopting a vapor deposition method to form the hydrophobic layer. The preparation method of the antifouling and antibacterial spectacle lens coating has the advantages of being antibacterial, antifouling and high in durability.

The invention discloses an MOF-CQD enzyme-sensitive FRET hydrogel diagnosis and treatment probe as well as a preparation method and application thereof, and belongs to the technical field of biomedical detection and treatment. The probe takes a carboxyl carbon quantum dot (CQD) as a donor and a metal organic framework (MOF) as an acceptor, and the donor and the acceptor are connected through a replaceable enzyme response polypeptide bridge; when the fluorescence is complete, FRET is generated to quench the CQD fluorescence, the FRET is interrupted after the target enzyme cuts off the peptide bridge, and the blue / red fluorescence ratio is changed to realize nanomole-level quantitative detection and has self-correction capability. The probe is packaged in a four-arm PEG transparent hydrogel which does not need a photoinitiator and can be quickly self-crosslinked, and can be prepared into a film, a tooth socket and the like for POCT (point-of-care testing) of parts such as an oral cavity / skin and the like. After detection, the MOF is activated by illumination of 630-660 nm to generate active singlet oxygen, so that local antibacterial or anti-tumor treatment is realized, and a diagnosis and treatment integrated scheme is constructed.

The invention relates to a recyclable composite water purifying agent and a preparation method thereof, and belongs to the technical field of high polymer materials. The recyclable composite water purifying agent comprises the following components in parts by weight: 12-18 parts of activated carbon, 20-25 parts of diatomite, 15-25 parts of polyaluminum chloride, 6-12 parts of a modified flocculant, 5-10 parts of polyethylene glycol, 1-3 parts of a modified photocatalyst and 250-370 parts of deionized water, the recyclable composite water purifying agent prepared by the invention not only has a good pollutant adsorption effect, but also has an excellent antibacterial effect.

A male cap can include a male tapered outer surface that can be configured to mate with a female luer to create a fluid tight fit. The male cap can also include a water-soluble antimicrobial composition disposed on the male extension. The male cap can include a fluid-soluble, slower-dissolving material covering the water-soluble antimicrobial composition or incorporated within the water-soluble antimicrobial composition. The slower-dissolving material can be configured to slow a dissolution of the water-soluble antimicrobial composition during installation of the male cap into the female luer.

Provided is an antibacterial peptide having an amino acid sequence X1KRFKKFFX2KLKKWV-NH2, wherein X1 is selected from any one or of amino acids A, C, D, E, F, G, H, K, L, N, M, P, Q, R, S, I, V, W, Y, and T or is absent; and X2 is an amino acid having an aromatic side chain or an amino acid having an alkaline side chain. In view of defects such as poor gastrointestinal fluid stability of antibacterial peptides in the prior art, a brand-new sequence design scheme and preparation method for an antibacterial peptide are provided. By means of a complete or partial D-amino acid substitution or structural derivatization of a peptide sequence, a series of antimicrobial peptides having stronger antibacterial activity and gastrointestinal stability as compared with the prior art are obtained, such that the antibacterial peptides have a wider application range and higher development potential value.

The invention relates to the technical field of inorganic non-metallic materials, in particular to a quaternized cholic acid polyurethane modified polyvinyl chloride material, a preparation method and application. The quaternized cholic acid polyurethane polymer is based on a polyurethane elastomer developed by using cholic acid molecules with a rigid skeleton as a hard segment unit and flexible oligomeric ethylene glycol as a soft segment unit, hydroxyl on cholic acid polyurethane is quaternized to prepare cation modified cholic acid polyurethane, and the cation modified cholic acid polyurethane simulates amphiphilic characteristics of natural peptides. The quaternized cholic acid polyurethane is introduced into a polyvinyl chloride (PVC) matrix as an antibacterial agent, so that the growth of microorganisms such as bacteria and molds can be effectively inhibited, the antibacterial property is achieved, bacteria breeding on the inner surface of a pipeline is avoided, and the composite material is endowed with better biocompatibility and antibacterial property; meanwhile, the quaternized cholic acid polyurethane can effectively improve the strength and toughness of the PVC material; wide application prospects are realized.

The invention relates to a novel application of animal bifidobacterium subsp. Lactis BGI-N3, in particular to an application of the animal bifidobacterium subsp. Lactis BGI-N3 in preparation of a preparation for relieving skin allergy. The invention finds that the bifidobacterium animalis subsp. Lactis BGI-N3 has a very remarkable effect in the aspect of relieving skin allergy, and the effect is specifically shown as follows: in an atopic dermatitis animal model, the dermatitis score, scratching times and percutaneous water loss are remarkably reduced, and the atopic dermatitis skin tissue damage condition is relieved; the immune organ edema condition is improved, the levels of Th2 type cell factors and inflammatory factors IL-6, TNF-alpha and IFN-gamma related to dermatitis are reduced, and the immune balance of the body is recovered; expression of fibroin and endothelial protein in skin tissue is improved, and the skin barrier is repaired; the level of antibacterial peptide in skin tissues is recovered, and the antibacterial activity of the skin is enhanced. Meanwhile, compared with a traditional chemical medicine for treating atopic dermatitis, the animal bifidobacterium subsp. Lactis BGI-N3 has no side effects such as weight loss, immune organ atrophy, immune imbalance and the like.

The invention discloses an amphiphilic chitosan and plant nanocellulose composite coating fresh-keeping material, which is prepared from the following ingredients in percentage by mass: 0.5 to 20 percent of amphiphilic chitosan, 0.1 to 5.0 percent of plant nanocellulose, 0.5 to 10.0 percent of coalescing agents, 0.1 to 3.0 percent of antioxidants and the balance deionized water. Wherein the amphiphilic chitosan is prepared from chitosan, quaternary phosphonium salt and sorbic acid. Amphipathic chitosan of the material has hydrophilic groups such as amino and carboxyl and a sorbate hydrophobic group, has hydrophilicity and hydrophobicity at the same time, and is extremely easy to combine with substances such as a coalescing agent, plant nanocellulose and an antioxidant to form a stable polymeric membrane layer, so that the mechanical property after membrane formation is remarkably improved, and the material has a good application prospect. Meanwhile, the plant nanocellulose particles can be stably coated in the polymeric membrane material layer, so that the mechanical property of the material is enhanced, and lasting and efficient antibacterial and antioxidant effects are realized. The invention further discloses a preparation method and application of the amphiphilic chitosan and plant nanocellulose composite coating fresh-keeping material.

The invention discloses a hydrogel dressing with a double-slow-release effect as well as a preparation method and application of the hydrogel dressing. The preparation method of the hydrogel dressing comprises the following steps: firstly, preparing methyl acrylate modified hyaluronic acid capable of being photo-crosslinked, then preparing carboxymethyl chitosan nanoparticles loaded with chlorogenic acid, and finally, mixing the methyl acrylate modified hyaluronic acid and the carboxymethyl chitosan nanoparticles loaded with chlorogenic acid to obtain the hydrogel dressing. The hydrogel dressing embedded with the nanoparticles is obtained in a photo-crosslinking mode. The hydrogel dressing provided by the invention not only has good biocompatibility and mechanical properties, but also plays an anti-oxidation role by removing free radicals in a body, and can effectively kill bacteria such as escherichia coli and staphylococcus aureus to play an antibacterial role. The hydrogel dressing can also reduce excessive inflammatory response in the wound healing process by influencing macrophage polarization, promote chronic wound healing and relieve pain of patients.

The invention belongs to the field of high polymer material chemistry, and particularly relates to double-network hydrogel based on sodium alginate / gelatin, a preparation method and dressing. A chemical method of grafting modification is adopted, grafting modification is carried out by designing abundant active groups on side chains of gelatin and sodium alginate, and based on traditional gelatin or sodium alginate hydrogel, not only is the thermal stability of gelatin improved, but also the biological activity of sodium alginate is improved, and the antibacterial property is achieved; the finally prepared SD / GelMA dual-network hydrogel wound dressing not only has excellent mechanical properties, but also has very high biocompatibility and antibacterial activity, and has huge application prospects and potential in the aspect of skin wound healing.