287 results about "Nano hydroxyapatite" patented technology

The invention belongs to the technical field of biomedical engineering, and particularly relates to a preparation method and application of a titanium dental implant surface coating, and the preparation method comprises the following steps: S1, pretreatment of a titanium dental implant matrix: sequentially carrying out grinding and polishing, ultrasonic cleaning and acid etching treatment; s2, preparation of a coating precursor solution: adding nano-hydroxyapatite powder, chitosan, gelatin and titanium dioxide nanoparticles into deionized water, stirring to form a suspension, then adding a silver nitrate solution, and continuously stirring to form the coating precursor solution; s3, coating a coating: coating the surface of the pretreated titanium dental implant matrix with the coating precursor solution by adopting an electrophoretic deposition method; and S4, drying and sintering: drying and sintering the coated titanium dental implant. According to the preparation method of the titanium dental implant surface coating, provided by the invention, the bonding strength between the coating and the titanium dental implant matrix can be improved.

The invention relates to the field of multifunctional coatings, in particular to a multifunctional coating based on acrylic resin and a production process of the multifunctional coating. Comprising the following raw materials in parts by weight: 40-60 parts of water-based acrylic resin emulsion, 0.3-0.6 part of a defoaming agent, 3-5 parts of modified nano hydroxyapatite, 0.3-0.5 part of a flatting agent, 2-5 parts of a dispersing agent, 1-3 parts of a curing agent, 3-5 parts of modified nano aluminum oxide and 30-50 parts of deionized water. The grafted chloroprene rubber can improve the interfacial compatibility of the nano-hydroxyapatite and a matrix and endows the coating with wear resistance, and after the nano-alumina is grafted with polybenzimidazole, a benzimidazole ring interacts with the matrix to enhance the interfacial compatibility of the nano-alumina and the matrix, so that the nano-alumina forms a high-temperature-resistant structure in the coating, and the wear resistance of the coating is improved. And the aromatic heterocyclic structure of the polybenzimidazole can endow the coating with higher thermal decomposition temperature, so that the coating has high temperature resistance.

The invention discloses a tooth repair composition containing mesoporous hydroxyapatite, a tooth repair product and a preparation method and application of the tooth repair composition and the tooth repair product. The tooth repair composition comprises nano-hydroxyapatite, fluoride and a chelating agent, the logarithm value logK of the stability constant K of the chelating agent to calcium ions is 1 < = logK < = 5, and K is measured in an aqueous solution with the temperature of 25 DEG C, the pH value of 7.0 and the ionic strength of 0.1 M; the nano-hydroxyapatite is prepared from nano-scale mesoporous hydroxyapatite, and the nano-hydroxyapatite contains nano-scale mesoporous hydroxyapatite. By adding the specific chelating agent, dynamic balance is formed in the tooth repairing composition, slow release protection can be formed on free calcium ions, the double inactivation effect possibly occurring when hydroxyapatite and fluoride exist at the same time is effectively avoided, the synergistic repairing effect of hydroxyapatite and fluoride is fully exerted, and the tooth repairing effect is improved. The use of fluorides can be greatly reduced, and safety and reliability are achieved.

The invention provides a composite hydrogel for infectious bone defect repair and a preparation method thereof, and belongs to the technical field of bone defect repair, the composite hydrogel comprises a three-dimensional porous network structure hydrogel and a bioactive unit, and the bioactive unit is loaded in the three-dimensional porous network structure hydrogel; the hydrogel with the three-dimensional porous network structure is prepared from photo-crosslinked methacrylated silk fibroin and nano-hydroxyapatite; the bioactive unit comprises a strontium metal organic framework loaded with curcumin. According to the invention, the photo-crosslinked methacrylated silk fibroin provides excellent biocompatibility; as an ion / drug dual carrier, the strontium metal organic framework can continuously release strontium ions and bidirectionally regulate bone metabolism (promoting osteogenesis and inhibiting osteoclast), and the porous structure of the strontium metal organic framework can efficiently load a hydrophobic drug curcumin (Cur). Curcumin has strong antibacterial and anti-inflammatory functions; the nano-hydroxyapatite can obviously enhance the mechanical strength of the hydrogel.

The invention discloses a humanized osteoporosis mouse model and a construction method thereof, and belongs to the technical field of biotechnology and animal models. The invention aims at the core defects of large species difference, insufficient humanization degree, low pathological simulation degree, unstable phenotype and the like of the existing osteoporosis model. The humanized osteoporosis mouse model is constructed through five core steps of experimental animal pretreatment, collagen-nano hydroxyapatite bionic scaffold preparation and cell pre-implantation, immune-bone metabolism double-derived system construction, progressive osteoporosis induction and model identification and verification. According to the method, double-person origination of immune and bone metabolism systems is realized for the first time, the colonization rate and survival time of human cells are greatly improved, the pathological process of clinical postmenopausal osteoporosis is accurately simulated, the phenotype of the model is stable and uniform, the reactivity matching degree with clinical drugs is high, and the method can be widely applied to research and development of anti-osteoporosis drugs and research of pathological mechanisms.

The invention provides a method for preparing a degradable bone-guided regeneration membrane with an asymmetric membrane layer, which comprises the following steps of: cutting a magnesium metal sheet into a magnesium net or a magnesium bracket with small holes by laser, carrying out heat treatment on the magnesium net or the magnesium bracket by using HF (Hydrogen Fluoride) to obtain a layer of MgF4 coating on the surface, and immersing the magnesium net or the magnesium bracket into a macromolecular solution until a solvent of the macromolecular coating is completely volatilized; then preparing an electrostatic spinning membrane on the surface of the sample: preparing a dense polymer membrane layer containing an antibacterial drug on the surface of the sample close to one side of the fiber tissue by adopting a hot pressing method, or preparing a dense electrostatic spinning ordered fiber membrane which contains an antibacterial nano-drug and is arranged in parallel by adopting an electrostatic spinning method; the designed structure and the used materials can realize an antibacterial function and shield fiber tissues from growing in. The nanofiber membrane which contains osteogenesis promoting substances such as nano-hydroxyapatite or nano-strontium and is conveyed disorderly is prepared on the side close to the bone tissue by adopting an electrostatic spinning technology, and the designed structure and the contained substances can promote osteogenesis.

This invention discloses a composite coating for the tooth surface of an atlantoaxial PEEK interbody fusion cage, relating to the field of medical materials technology. The composite coating for the atlantoaxial PEEK interbody fusion cage comprises a transition layer covering the tooth surface of the atlantoaxial PEEK interbody fusion cage and a hydroxyapatite coating on the surface of the transition layer; the transition layer is obtained by mixing modified nano-hydroxyapatite and modified PEEK; the hydroxyapatite coating is obtained by plasma spraying of nano-hydroxyapatite. This application sets a transition layer between the PEEK and the hydroxyapatite coating, effectively addressing the problem of easy coating detachment due to the difference in physicochemical properties between the PEEK and hydroxyapatite coatings. The composite coating prepared in this application improves the bonding strength between the coating and the substrate, and the prepared material can be used in biological organisms for a long time.

The invention relates to an injectable hydroxyapatite microsphere as well as a preparation method and application thereof, and belongs to the technical field of hydroxyapatite microspheres, the preparation method comprises the following steps: uniformly mixing nano hydroxyapatite, an adhesive and a dispersing agent to obtain mixed slurry; carrying out spray drying on the mixed slurry to obtain spray-dried microspheres; and carrying out high-temperature calcination on the spray-dried microspheres to obtain the injectable hydroxyapatite microspheres. The preparation method provided by the invention is simple, and the porous hydroxyapatite microspheres with high sphericity, good particle size distribution uniformity and no adhesion can be obtained by spray drying and high-temperature calcination of the mixed slurry without other treatments such as ball milling.

The invention belongs to the field of catalyst preparation, and particularly relates to a binder for catalyst forming and a preparation method and application thereof. The binder for forming the catalyst, provided by the invention, is prepared from the following raw materials in parts by weight: 0.5 to 2 parts of magnesium chloride, 1 to 2 parts of magnesium oxide, 0.5 to 2 parts of sodium carboxymethyl cellulose, 1 to 3 parts of ethylenediamine tetraacetic acid, 2 to 6 parts of nano-hydroxyapatite modified polyester, 1 to 3 parts of organic solvent and 10 to 35 parts of water. When the binder provided by the invention is applied to catalyst forming, on one hand, the problems that a conventional catalyst is poor in binding performance, and acid gas corrodes equipment and pollutes the environment in the roasting process can be solved; on the other hand, the surface acidity of the catalyst carrier can be reduced, a suitable reaction environment can be provided for some reactions needing to be carried out in an alkaline environment or reactions with acidic reactants and intermediates, and the selectivity and conversion rate of the reactions are improved.

The invention belongs to the technical field of biomedical materials, and particularly relates to a callus-imitating bone adhesive as well as a preparation method and application thereof. And carrying out second polymerization reaction on hydrogen atoms in the type I collagenous fibers and isocyanate groups in the callus-imitating polyurethane bone adhesive prepolymer to obtain the callus-imitating bone adhesive, wherein the callus-imitating polyurethane bone adhesive prepolymer is obtained by carrying out a polyaddition reaction on hydroxyl groups in nano-hydroxyapatite and isocyanate groups in a hexamethylene diisocyanate tripolymer, and the biocompatibility of the material is obviously improved through a novel biological soft segment, namely the I-type collagenous fiber. Meanwhile, in the polymerization process of the material, thermal infrared characterization shows that the material does not generate heat higher than the temperature of a human body and does not cause thermal damage to tissues.

The invention belongs to the technical field of organic fertilizer preparation, and relates to an organic fertilizer for heavy metal soil pollution and a preparation method thereof.The preparation method specifically comprises the following steps that nano-hydroxyapatite, Mg-Al-LDH, compound bacterium powder, normal saline and modified biochar are mixed and oscillated, and a compound functional base material is obtained; mixing and granulating the composite functional base material, the fermented organic matter and the binder, and coating the granules to obtain the organic fertilizer, according to the invention, through the material composite design of nano-hydroxyapatite / Mg-Al-LDH / modified charcoal, a microorganism-passivator preloading process, a coating technology and other technologies, the defects of single function, low microorganism survival rate, short-term effect of remediation and the like of the existing organic fertilizer exposed in the heavy metal contaminated soil are overcome.

This invention provides a solid waste-based backfill material for improving heavy metal leaching rate and its preparation method. The backfill material comprises the following raw materials in parts by weight: 40-60 parts Bayer red mud, 40-60 parts fly ash, 10-20 parts desulfurized gypsum, 5-8 parts nano-hydroxyapatite, 4-6 parts pumping agent, and 30-60 parts water. The pumping agent is a compound of organosilicon polycarboxylic acid water-reducing agent, polymaleic acid, and thiol-modified cellulose in a mass ratio of 4-6:3:10-12. The thiol-modified cellulose is prepared by a method including the following steps: dissolving carboxymethyl cellulose in water, adding aminothiol compounds, adjusting the pH, adding activators and activating aids, and reacting under controlled temperature. After the reaction, acetone is added until no precipitation occurs. The mixture is then filtered, washed, and dried to obtain thiol-modified cellulose. The heavy metal leaching performance of the backfill material is improved by introducing hydroxyapatite, which can both precipitate and adsorb heavy metals.

The invention discloses a preparation method of a growth factor gradient bionic scaffold for tendon-bone interface regeneration and repair, and belongs to the technical field of biomedical materials. The composite scaffold is constructed by adopting a coaxial electrospinning and self-assembly technology, and is compounded by a core-shell oriented nanofiber layer and a non-oriented nanofiber layer through a gelatin adhesive to respectively simulate tendon phase and bone phase structures of a tendon-bone interface; a shell layer of the tendon-phase-simulated core-shell oriented nanofiber is a PCL layer containing CTGF, a core layer of the tendon-phase-simulated core-shell oriented nanofiber is a PVA layer containing TGF-beta1, and a bone-phase-simulated non-oriented nanofiber layer is a PCL / Gel co-spun layer containing BMP-2 polylactic acid microspheres and nano-hydroxyapatite. The scaffold can realize secondary controlled release of early-stage release of CTGF, slow release of TGF-beta1 in the middle and later periods and continuous release of BMP-2, and cooperates with a fiber orientation structure to induce graded differentiation of mesenchymal stem cells and promote integrated repair of a tendon-bone interface gradient structure, so that the problems of poor healing of a tendon-bone interface and high repeated fracture rate in a traditional repair method are solved, and the scaffold has good application prospects. The important application value is realized in the field of tendon-bone injury treatment in sports medicine.

The invention relates to the technical field of high-molecular compounds, in particular to a PTFE microporous membrane and a preparation method and application thereof. The composite conductive material is prepared from the following components in parts by weight: 55 to 65 parts of PTFE dispersion resin, 5 to 8 parts of graphene quantum dot / carbon nanotube and metal organic framework composite conductive phase, 6 to 9 parts of POSS-graphene hybrid modified nano silicon dioxide, 7 to 10 parts of fluorosilane grafted polyether-ether-ketone-polyimide block copolymer, 3 to 5 parts of nano hydroxyapatite-chitosan composite particles and 10 to 15 parts of composite pore-foaming agent. 1 to 3 parts of organic montmorillonite; wherein the grafting rate of the block copolymer is 25-30%, the fluorine content is 12-15 wt%, and the silicon-oxygen bond density is 0.8-1.2 mmol / g. The preparation method has the advantages of good mechanical properties and stability, multifunction synergy, pollution resistance, good biocompatibility, process optimization, improvement of consistency, meeting of multi-field requirements, and wide application prospect.

The invention discloses a preparation method of a gradient pore-forming magnesium-containing calcium phosphate bone repair material, which comprises the following steps: S1, mixing nano-hydroxyapatite with polylactic acid-glycolic acid copolymer (PLGA) powder, adding dichloromethane as a solvent, continuously stirring to form a solution, and freeze-drying to obtain an nHA / PLGA raw material, and carrying out high-temperature fused deposition through a 3D biological printer to prepare the degradable nPLGA stent. S2, weighing the calcium phosphate bone cement powder and the magnesium metal microspheres according to a preset mass ratio, stirring the slurry and homogenizing to obtain calcium phosphate bone cement slurry containing the magnesium metal microspheres; s3, injecting the calcium phosphate bone cement slurry obtained in the step S2 into the nPLGA stent prepared in the step S1 to obtain an MC / nPLGA compound; gradient micropores are generated through hydration reaction of the magnesium microspheres, the gradient micropores and macropores formed by degradation of PLGA form a complementary structure, and the total porosity reaches 68% and is increased by 3.4 times compared with traditional CPC.

The invention relates to the technical field of biomedical material synthesis, in particular to a synthetic method of a bionic gradient mineralized collagen-polycaprolactone composite material, which comprises the following steps: a) activating the surface of PCL (polycaprolactone) through argon plasma to generate carboxyl groups with the density of more than or equal to 5 * 10 / cm; b) carrying out amination modification on nano-hydroxyapatite (nHA) by adopting APTES, wherein the surface potential of the modified nHA is greater than or equal to + 15 mV; c) covalently grafting aminated nHA to the surface of PCL through an amido bond under the conditions that the molar ratio of EDC / NHS is 1: 2 and the pH is 5.5 + / -0.2, and the grafting density is greater than or equal to 3 * 10 particles / mu m; the method has the beneficial effects that the gradient mineralization structure is subjected to bionic optimization: the concentration and the flow velocity (the inner / outer layer flow velocity ratio is 1: 3) of mineralization liquid are accurately controlled through a microfluidic gradient generator, linear gradual change (the gradient slope is 1.5 + / -0.3 wt% / 100 [mu] m, R is equal to 0.97) of the mineralization degree from 20-30 wt% of the inner layer to 50-60 wt% of the outer layer is realized, the mechanical gradient characteristics of the natural bone are simulated, the compression modulus is increased from 0.8 GPa of the inner layer to 3.2 GPa of the outer layer in a gradient manner, and the mechanical property of the natural bone is improved. The mechanical matching property of the material and the host bone is obviously improved.

The invention relates to a composite carbon source and application thereof in sewage denitrification nitrogen removal, and belongs to the technical field of sewage treatment.The composite carbon source is obtained by forming a gel network through polyvinyl alcohol and sodium alginate, then crosslinking the gel network with calcium ions in calcium chloride to form a three-dimensional framework, and wrapping modified composite powder and polylactic acid in the three-dimensional framework. The three-dimensional skeleton can provide certain mechanical strength, so that the internal carbon source can resist water flow scouring, the porous structure can also enable the internal carbon source to be slowly released, more pores are formed after Na-montmorillonite and iron-carbon powder are compounded, the loading rate of flaky nano-hydroxyapatite on the montmorillonite intercalated iron-carbon powder is further improved, and the adsorption capacity of the montmorillonite intercalated iron-carbon powder is improved. Hydroxyl groups in the flaky nano-hydroxyapatite can form hydrogen bonds with Na-montmorillonite and hydroxyl groups on a three-dimensional skeleton, the interface bonding force is improved, the mechanical strength of the composite carbon source is further improved, polylactic acid serves as a slow-release carbon source and is gradually hydrolyzed under the action of microorganisms, and the release period of the composite carbon source under continuous impact of high-speed water flow is prolonged.

The invention discloses an environmental response type degradable bionic composite membrane and a preparation method thereof, the composite membrane is formed by alternately stacking hydrophobic layers and hydrophilic layers, the hydrophobic layers are PHA / PBS (3: 1-5: 1) blends and added with 2-8 wt% of oleic acid grafted nano-hydroxyapatite, and the hydrophilic layers are modified starch / PVA composite materials with the crosslinking degree of 15-35% and contain 0.5-3 wt% of thermo-sensitive PNIPAM-b-PAA. Mechanical interlocking is realized between layers through a lotus leaf-like micro-nano mastoid structure (the height is 1-5 microns, and the density is 106-107 / cm < 2 >) treated by plasma; micro gravure coating, electrostatic spraying and blade coating processes are adopted for preparation, and the controllable degradation period of 30-180 days can be achieved by regulating and controlling the layer thickness ratio (1: 2-3: 1); the degradation rate of the material in the pH range of 5.5-8.5 is positively correlated with the pH value (R2 is greater than 0.95), the degradation rate is increased by 8-12% when the temperature is increased by 1 DEG C, the degradation rate is greater than 90% in 20-50 days under the composting condition, the degradation product is ecologically safe (LC50 is greater than 1000mg / kg), and the material is suitable for intelligent agricultural mulching films and environment-friendly packaging.

The invention discloses antibacterial and antiskid PU leather and a preparation method and application thereof, and belongs to the technical field of PU leather.The preparation method comprises the steps that a ZIF-8 / g-CNcomposite photocatalyst is obtained through an in-situ growth method, silver-doped nano-hydroxyapatite is prepared through an ion replacement method, the ZIF-8 / g-CNcomposite photocatalyst and the silver-doped nano-hydroxyapatite are compounded through liquid phase adsorption, and the antibacterial and antiskid PU leather is obtained. The preparation method comprises the following steps: preparing composite antibacterial powder, uniformly dispersing the composite powder into acrylamide, Arabic gum and polyethylene glycol methyl ether methacrylate serving as monomers, initiating polymerization to form composite coating slurry, performing oxygen plasma activation on PU leather, blade-coating the composite coating slurry, and curing to obtain the antibacterial antiskid PU leather. The material integrates the functions of self-cleaning, antibiosis, skid resistance and wear resistance.

The invention relates to the technical field of asphalt mixture processing, in particular to a high-asphalt-aggregate-ratio durable basalt fiber asphalt mixture with low-temperature crack resistance and a preparation method of the high-asphalt-aggregate-ratio durable basalt fiber asphalt mixture. The preparation method comprises the following steps: (1) soaking cleaned basalt fibers in a hydrochloric acid solution for pretreatment to obtain pretreated basalt fibers; (2) adding nano-hydroxyapatite, carboxymethyl cellulose and dodecanoic acid into an ethanol water solution for heating reaction, and collecting a product after purification; (3) adding the product into acetone, then adding the pretreated basalt fibers, and stirring to obtain modified basalt fibers; and (4) uniformly mixing the modified basalt fiber, the asphalt, the mineral powder and the aggregate in parts by weight, thereby obtaining the composite material. The preparation method is simple and easy for large-scale production, and the prepared mixture has excellent low-temperature crack resistance, water stability and high-temperature stability, which is of great significance for improving the quality of road engineering and prolonging the service life.

The invention provides a drug-loaded sophorolipid microsphere, a preparation method thereof and application of the drug-loaded sophorolipid microsphere in preparation of a bionic cartilage scaffold. The preparation method of the drug-loaded sophorolipid microspheres comprises the following steps: (1) preparing a drug-containing sophorolipid solution; (2) preparing multiple emulsion; and (3) adding a horse radish peroxidase solution into the multiple emulsion for reaction to obtain the drug-loaded sophorolipid microspheres. The bionic cartilage scaffold sequentially comprises a bone layer, a transition layer and a cartilage layer from bottom to top, the bone layer is a cross-linked compound of nano-hydroxyapatite and drug-loaded sophorolipid microspheres; the transition layer is a physical mixture of nano-hydroxyapatite and drug-loaded sophorolipid microspheres; the cartilage layer is drug-loaded sophorolipid microspheres. The drug-loaded sophorolipid microspheres disclosed by the invention have good biocompatibility, excellent biocompatibility and good mechanical properties. The bionic cartilage scaffold utilizes the characteristics of the nHA and the drug-loaded sophorolipid microspheres to form a unique network structure, so that material failure caused by mechanical mismatching is avoided.

The invention relates to the technical field of medical treatment, and particularly discloses dihydroartemisinin-loaded nano-hydrogel, which is prepared from the following components: 5 to 20 percent of gelatin methacryloyl, 5 to 15 percent of nano-hydroxyapatite and 0.5 to 2 percent of dihydroartemisinin, according to the invention, through the constructed Ge MA-nHA-DHA functionalized hydrogel system, the local concentration and bioavailability of dihydroartemisinin are remarkably improved, and the repair and regeneration of bone tissues are promoted. Research results show that the system can effectively inhibit inflammatory response, promote proliferation and differentiation of osteoblasts, improve the structure and function of bone tissues, slow down further collapse of femoral heads and finally improve the living quality of patients. In addition, the biological material shows good biocompatibility and appropriate drug release characteristics when applied in vivo, and a novel effective means is provided for treatment of steroid-induced femoral head necrosis.

The invention provides a high-strength fire-resistant cable and a preparation method thereof, and belongs to the technical field of cables, and the preparation method of the high-strength fire-resistant cable comprises the following steps: reacting nano-hydroxyapatite with 10-(2-methacryloyloxy) monodecyl phosphate in ethanol, and drying to obtain modified hydroxyapatite; ethylene-vinyl acetate copolymer, magnesium hydroxide, zinc borate, zinc stannate, polyethylene wax, vinyltrimethoxysilane, 2-hydroxy-2-methyl propiophenone and modified hydroxyapatite are mixed, melt-extruded and illuminated at constant temperature, and a sheath layer is obtained; mixing tetraethoxysilane, ethanol, dibutyltin dilaurate, fumed silica, phlogopite paper and glass fibers, heating and aging, and cutting to obtain a fireproof layer; the insulating layer, the fireproof layer and the sheath layer are sequentially coated on the conductor to prepare the high-strength fireproof cable, and the cable prepared by the invention has good mechanical property, electrical insulating property and fireproof property.

This invention relates to the field of biomedical technology, specifically to a biomimetic piezoelectric scaffold for promoting bone repair, its preparation method, and its applications. The biomimetic piezoelectric scaffold provided by this invention is produced by electrospinning PLLA into oriented nanofibers, and then modifying the fiber surface with nano-hydroxyapatite. To enhance the adhesion of hydroxyapatite to the fiber surface, a polydopamine layer is modified between the two as a connecting layer, ultimately resulting in a biomimetic piezoelectric scaffold with high porosity, good osteointegration, and osteogenic promoting effects. This scaffold exhibits good bone regeneration promoting effects in in vitro MSC recruitment, osteogenic differentiation experiments, and repair of skull bone defects in rats.

The invention relates to a high-breathability and high-fitness in-vitro fixing device with a shape memory function and a preparation method of the high-breathability and high-fitness in-vitro fixing device, and relates to the field of biomedical materials, the high-breathability and high-fitness in-vitro fixing device comprises the following components in parts by mass: 40-45 parts of polycaprolactone, 40-45 parts of polylactic acid, 4-6 parts of a compatilizer, 0.5-1.5 parts of a cross-linking agent, 8-12 parts of nano-hydroxyapatite, 10-20 parts of biocompatible polyurethane and 0.1-0.3 part of a coloring agent. The preparation method comprises the following steps: mixing the raw materials, carrying out melt blending, and carrying out extrusion granulation to obtain composite particles; the composite particles are subjected to melt-blowing spinning, and non-woven cloth is obtained; and carrying out hot press molding on the non-woven fabric, shaping and cooling to obtain the high-breathability and high-fitness in-vitro fixing device with the shape memory function. The in-vitro fixing device prepared by the invention has a silk net structure, has good air permeability, a shape memory function and fitness, and has good mechanical properties and antibacterial properties.

The present application relates to the technical field of composite biological coating. Specifically, the present application relates to a hydrophobic composite layer on a medical degradable magnesium alloy substrate and a preparation method thereof. In the preparation method, firstly, a porous ceramic oxide layer is formed on the magnesium alloy substrate through micro-arc oxidation treatment, so as to reduce the corrosion rate of the magnesium alloy; then, a strontium-doped hydroxyapatite layer is prepared on the surface of the micro-arc oxidation layer using a chemical deposition method, so as to improve the biocompatibility of the magnesium alloy; finally, the magnesium alloy subjected to the micro-arc oxidation and chemical deposition treatment is immersed and pulled once or more times in a polylactic acid solution containing nano-hydroxyapatite, so as to form a hydrophobic polymer layer. The hydrophobic composite layer prepared by the present application improves the corrosion resistance and biocompatibility of the magnesium alloy at the same time. The present application also relates to a magnesium alloy implant product comprising the hydrophobic composite layer.

A dental varnish composition for promoting enamel remineralization may comprise nano-hydroxyapatite particles dispersed in a biocompatible resin matrix that forms an adhesive film on tooth enamel. The composition may include a solvent to facilitate uniform dispersion and one or more additives. The resin matrix may be hydrophilic to enhance adhesion and wetting of enamel microstructures. Contact with saliva triggers controlled, gradual release of nano-hydroxyapatite, providing sustained remineralization benefits and protection against demineralization over an extended period. The nano-hydroxyapatite may penetrate enamel microstructures and repair microlesions, while optionally reducing dentin hypersensitivity. The composition may be fluoride-free and formulated with defined weight ratios of resin, particles, and solvent. A method of treatment includes applying the varnish to tooth surfaces, forming the adhesive film, and allowing slow release of nano-hydroxyapatite to strengthen enamel.

The invention provides a mussel bionic composite adhesive and a preparation method thereof, and belongs to the technical field of high-performance adhesives. The composite material is prepared from 88 parts by mass of premixed mother liquor, 3-6 parts by mass of a silane coupling agent KH-560 and 4-8 parts by mass of nano-hydroxyapatite, 3, 4-dihydroxy phenyl methacrylamide is taken as an adhesion function core of the premixed mother liquor, is cooperated with 2-ethylhexyl acrylate and isobornyl methacrylate, and is compounded with a specific composite photoinitiator, an antioxidant 1010 and an ultraviolet absorbent 328. The preparation method comprises the following steps: preparing premixed mother liquor under the dark condition of 30 DEG C, primarily dispersing the premixed mother liquor, the silane coupling agent and the nano-hydroxyapatite under normal pressure, and performing vacuum stirring, dispersing and degassing under-0.05 to-0.08 MPa. The adhesive has excellent adhesion to inorganic base materials such as hydroxyapatite and natural stone, has compressive strength of more than or equal to 22MPa and high elongation at break of 35-55%, has outstanding weather resistance and stable performance after long-term ultraviolet aging, and is suitable for the fields of medical bone repair material fixation, stone adhesion, high-end composite material forming and the like.

The invention provides a wound dressing for wound hemorrhage. The wound dressing is prepared from the following components in parts by mass: 20 to 25 parts of cationic cassava starch, 10 to 13 parts of polyethylene glycol, 1.2 to 1.8 parts of xanthan gum, 0.1 to 0.2 part of cannabidiol, 6 to 8 parts of tannic acid modified chitosan, 1.8 to 2.5 parts of a polydopamine solution with the concentration of 5mg / mL and 1 to 1.5 parts of nano-hydroxyapatite. The wound dressing has an instant hemostatic effect and a long-acting tissue regeneration induction capability.

The invention provides a full-biodegradable multifunctional agricultural mulching film material and a manufacturing method, and relates to the technical field of material processing, the full-biodegradable multifunctional agricultural mulching film material comprises a mulching film material, the mulching film material comprises a core biodegradable base material, a multifunctional modification auxiliary agent, an environmental response type slow release functional component and a multi-scale enhancement system, according to the invention, polycaprolactone and a starch grafted copolymer are compounded in a core biodegradable base material, and a multi-scale enhancement system (modified cellulose nanocrystals and nano-hydroxyapatite) and a high-shear directional mixing process are combined, so that the biodegradable material is prepared; and a three-dimensional nano support network structure in the membrane is realized. According to the structure, the tensile strength and the elongation at break of the film are effectively improved, the film can still keep integrity under the conditions of long-period covering and agricultural machinery operation, flexibility and toughness are both considered, and the problems that a traditional biodegradable mulching film is prone to breakage and poor in durability are solved.