88 results about "Polylactide co glycolide" patented technology

The invention relates to the technical field of biomedicine, and discloses a triclosan antibacterial coating surgical suture and a preparation method thereof.The suture comprises a base material and a surface antibacterial coating, the base material is selected from one of an absorbable single-strand material, an absorbable multi-strand material, a non-absorbable single-strand material and a non-absorbable multi-strand material, and the surface antibacterial coating is selected from one of an absorbable multi-strand material and a non-absorbable multi-strand material; the antibacterial coating comprises triclosan, a high-molecular carrier and an auxiliary agent, the surface energy of a hydrophobic material is improved, the porosity of a hydrophilic material is increased, the adhesive force between the coating and different base materials is ensured, the base materials can be covered, the uniformity deviation of the coating is avoided, and the coating is free of cracking or falling off through the combination of plasma cleaning and roughening treatment on the surface of the base materials. A synergistic system is formed by triclosan, nano-silver and titanium dioxide, a dual mechanism of targeted destruction of bacterial cell membranes and free radical oxidation is achieved, the antibacterial rate is increased, the MRSA inhibition rate is increased, the degradation rate is regulated and controlled through the polylactic acid-glycolic acid copolymer carrier molecular weight and the lactic acid / glycolic acid proportion, and a curing dynamic formula is combined.

The invention relates to the technical field of medical gel, and particularly discloses a sustained-release gel preparation for endometrial repair and a preparation method of the sustained-release gel preparation. Keratinocyte factor sustained-release microspheres containing keratinocyte factor-glucan particles and lactic acid-glycolic acid copolymer shells are constructed around keratinocyte factors, and the keratinocyte factor sustained-release microspheres are loaded by hyaluronic acid hydrogel containing polylysine, collagen and silk fibroin to form the sustained-release gel preparation for endometrial repair. The sustained-release gel preparation has the effect of promoting proliferation of human endometrial cells, can repair endometrial injury, promote injury healing and prevent uterine cavity adhesion, and has important significance in treating endometrial injury and improving physical and psychological health of women.

The present invention relates to a sustained release microsphere and a sustained release preparation comprising a GLP-1 receptor agonist or a pharmaceutically acceptable salt thereof. The present invention relates to a sustained release formulation, and more specifically, to a sustained release formulation comprising a GLP-1 receptor agonist or a pharmaceutically acceptable salt thereof, the sustained-release microparticles comprise a GLP-1 receptor agonist or a pharmaceutically acceptable salt thereof, one kind of low-viscosity polylactic acid-glycolic acid copolymer (PLGA) having an intrinsic viscosity of 0.14 dL / g to 0.24 dL / g, and two or more kinds of high-viscosity polylactic acid-glycolic acid copolymers having an intrinsic viscosity of 0.32 dL / g to 0.60 dL / g, so that the sustained-release microparticles do not have the problems of excessive release and delayed release in the initial stage of a drug. Long-term sustained release can be realized, and the bioavailability is excellent.

The invention provides a composition for changing plasticity of bone meal particles as well as a preparation method and application of the composition, and relates to the technical field of biomedical materials. The composition is prepared from the following raw material components: bioactive glass, dihydrazide modified sodium hyaluronate, sodium hyaluronate with the molecular weight of 50kDa to 500kDa, a polylactic acid-glycolic acid copolymer and carboxymethyl cellulose. The preparation method of the dihydrazide modified sodium hyaluronate comprises the following steps: carrying out carboxyl activation on sodium hyaluronate, carrying out a cross-linking reaction on the activated hyaluronic acid and adipic dihydrazide, and then terminating the reaction. The composition provided by the invention not only can provide support, but also can adjust the degradation rate to be matched with the bone regeneration period, and all the components synergistically improve the mechanical property and the viscoelastic property. The composition disclosed by the invention can be formed in situ at a bone defect part, provides a space for growth and proliferation of bone cells, improves the biological activity and osteoinductivity of an artificial bone, and promotes bone growth and repair.

The application discloses a water-soluble quantum dot nanometer material and a preparation method and application thereof, and the nanometer material comprises quantum dots and carboxyl-terminated poly(lactic-co-glycolic acid) coated on surfaces of the quantum dots. The carboxyl-terminated poly(lactic-co-glycolic acid) is used for encapsulating CsPbBr3 perovskite quantum dots, and a water-soluble perovskite nanocrystal material is prepared, which can retain high quantum yield (PLQY=88%) and water-oxygen resistance (>=30 days) and almost completely retains optical performance of the perovskite quantum dots.

The invention provides a long-acting microsphere sustained release preparation and a preparation method thereof, and belongs to the technical field of sustained release preparations, the long-acting microsphere sustained release preparation is prepared from the following raw materials of effective components: 9.5 to 10.5 parts of antipsychotic drug, 48 to 50 parts of hydroxypropyl-beta-cyclodextrin, 50 to 52 parts of polylactic acid-glycolic acid copolymer, 1.25 to 1.3 parts of glycerol triacetate and 10 to 11 parts of polyvinyl alcohol. The preparation method comprises the following steps: firstly, the hydroxypropyl-beta-cyclodextrin is used for clathration of the antipsychotic drug, the obtained clathrate compound is further clathrated by the polylactic acid-glycolic acid copolymer, and the long-acting microsphere sustained release preparation is obtained. According to the invention, the double-valve design of beta-CD and PLGA synergistic inclusion is utilized, so that the preparation can realize two-stage release; the macroscopic slow release characteristic of the PLGA is combined with the microcosmic express characteristic of the hydroxypropyl-beta-cyclodextrin, so that the technical limitation of a single carrier is broken through.

The invention discloses a hair-growing liniment and a preparation method thereof, and belongs to the technical field of pharmacy. The liniment comprises the following components in percentage by weight: 1-10% of minoxidil microspheres, 5-20% of a film-forming agent, 0.5-5% of a polypeptide compound, 5-30% of a liquid auxiliary material and the balance of deionized water. Wherein the minoxidil microspheres are of a three-layer structure composed of minoxidil in the inner layer, nano enzyme (cerium dioxide) in the middle layer and lactic acid-glycolic acid ester copolymer or chitosan in the outer layer, and controlled release and targeted delivery are achieved; the polypeptide compound is a compound of oldenlandia diffusa polypeptide and a copper curcumin derivative, and has the effect of synergistically repairing a hair follicle microenvironment. Tests prove that the liniment can remarkably prolong the release time of minoxidil, increase the retention volume of minoxidil in hair follicle parts and reduce absorption of the whole body, shows a hair growth promoting effect superior to that of a traditional preparation and a single-layer microsphere preparation in an animal model, and has good stability and use comfort.

The invention belongs to the technical field of medicine preparation, and particularly relates to an anti-HIV infection compound medicine microsphere composition, a medicine preparation and application. The invention firstly provides an anti-HIV (Human Immunodeficiency Virus) infection compound drug microsphere composition, which is composed of Cabotegravir, rilpivirine and at least one polylactic acid-glycolic acid copolymer, and comprises a first compound microsphere composition or a second compound microsphere composition, wherein one of the microsphere compositions is a co-coated microsphere formed by co-coating Cabotegravir and rilpivirine in the same microsphere; and the other microsphere composition is a mixture consisting of a microsphere for wrapping Cabotegravir and a microsphere for wrapping rilpivirine. The invention aims to provide a flexible preparation platform so as to optimize the long-acting treatment effect of the two anti-HIV drugs. For a composition form that one microsphere wraps two medicines, synchronous release and long-acting release of the two medicines are realized as much as possible; for another physically mixed composition form, independent regulation of release kinetics of a single drug is achieved as much as possible, so that the same administration cycle is achieved. The pharmaceutical preparation disclosed by the invention can be used for prevention before HIV exposure and long-term maintenance treatment of infected persons, and can be used for remarkably improving medication compliance and reducing the risk caused by virus drug resistance.

Provided are a bionic drug-loaded nanoparticle with expressed CXCR4, a method for preparing same, and use thereof. The method comprises: mixing a lactic acid-glycolic acid copolymer and an immunosuppressant in a certain ratio, and preparing the mixture into a drug-loaded nanoparticle using a microfluidic technology; preparing an MSC cell stably expressing membrane protein CXCR4 and lysing same to extract the cell membrane, so as to give an engineered stem cell membrane; and fusing the engineered stem cell membrane with the drug-loaded nanoparticle to give a bionic drug-loaded nanoparticle with expressed CXCR4. The bionic drug-loaded nanoparticle with expressed CXCR4 is a bionic cell membrane drug-loaded nanoparticle with chemotaxis functionality. By means of genetic engineering, the engineered stem cell membrane is modified to encapsulate a therapeutic agent, and directionally migrates to the lesions in the body and targets specific cells, thereby improving the drug distribution in vivo and reducing adverse effects of immunosuppressants.

The invention provides an anti-permeability and anti-sulfate corrosion additive for organic nano concrete, and belongs to the technical field of concrete. The additive disclosed by the invention contains ethylenediamine methylene sodium phosphate, sodium polyacrylate, sodium thiocyanate, polylactic acid-glycolic acid copolymer (PLGA), hydroxypropyl ethanolamine, a modified nano graphite material, chitosan quaternary ammonium salt, a silane coupling agent, nano volcanic ash powder and other components in a specific proportion. Wherein the modified nano-graphite material is prepared by modifying nano-graphite powder with polyether amine and a silane coupling agent; all the components are matched and the additive is prepared by adopting a special preparation method, and the additive has good impermeability and sulfate corrosion resistance when being used in concrete, and is stable and reliable.

The invention relates to the technical field of medical biological materials, and particularly discloses a composite electret flexible biological electrostatic electret patch and a preparation method thereof.The electrostatic electret patch comprises a backing layer, a medical pressure-sensitive adhesive layer and a functional layer which are sequentially arranged from outside to inside. According to the functional layer, at least one of polylactic acid, polyvinylidene fluoride and a polylactic acid-glycolic acid copolymer is selected as a polymer matrix to be compounded with graphene, a specific process combining ultrasonic dispersion and high-precision 3D printing is adopted, a deep-energy-level charge trap is introduced, the problems of high-conductivity filler agglomeration and surface charge leakage are solved, and the conductivity of the graphene is improved. The surface potential retention rate of the material can reach 60% or above after 900 days, the charge loss rate is not larger than 20% after 8-hour air exposure, and efficient physical electrostatic electret assisted sleep treatment under the drug-free and non-transdermal conditions is achieved.

A nanodiamond-reinforced nanofiber scaffold system for skin regeneration, consisting of a multilayered, electrospun nanofiber matrix formed from one or more biocompatible polymers selected from polycaprolactone (PCL), poly(lactic-co-glycolic acid) (PLGA), chitosan, gelatin or collagen, wherein nanodiamonds are present in an amount of 0.1 to 5 wt.-% are incorporated and surface-functionalized with oxygen, hydroxyl, or carboxyl groups to ensure homogeneous dispersion within the polymer matrix, the scaffold being characterized by a controlled fiber diameter in the range of 100 to 800 nm, an interconnected porosity between 60 and 90%, a tensile strength of 2 to 10 MPa, a degradation time of 2 to 8 weeks, and the ability to improve cell adhesion, proliferation, and migration of fibroblasts and keratinocytes, while simultaneously exhibiting antioxidant activity, reduced formation of reactive oxygen species, and the optional incorporation of bioactive agents selected from growth factors, antioxidants, or antimicrobial compounds to accelerate wound healing and skin tissue regeneration.

The present invention relates to the technical field of heterocyclic compound drugs and their preparation and application, and specifically to a tropane alkaloid composition for the treatment of COPD and its application. The composition combines tropane alkaloids, mannose-6-phosphate and polylactic acid-glycolic acid copolymer, and is constructed into a nanocomposite by nanoparticle preparation technology for aerosol inhalation administration. The composition aims to solve the problems of low bioavailability and lack of targeting in conventional administration of tropane alkaloids. Targeted delivery is achieved by introducing mannose-6-phosphate into the surface of nanoparticles, promoting drug enrichment in the lungs, and using polylactic acid-glycolic acid copolymer to control drug release, thereby increasing local drug concentration and therapeutic efficacy in the lungs.

The invention relates to the technical field of modified calcium carbonate, in particular to modified calcium carbonate, which comprises the following structures: an inner core: lithium battery recycled calcium carbonate slag, which comprises 1.2-1.8 wt% of Li2CO3 and 0.5-1.2 wt% of MgCO3; the middle layer is a polydopamine (PDA) coating film, the thickness of the polydopamine (PDA) coating film is 50-80 nm, and the polydopamine (PDA) coating film is used for providing active amino (-NH2); the shell is a fluorine-containing silane and polylactic acid-glycolic acid copolymer (PLGA) composite layer, the grafting rate is larger than or equal to 90%, and the molar ratio of lactic acid to glycolic acid of PLGA is 75: 25. Quantized data of performance improvement and dispersibility are as follows: the oil absorption value is 18 ml / 100 g (compared with 28-32 ml / 100 g in the prior art), and the bulk density is 0.25 g / cm < 3 > (loose agglomeration). Functions are as follows: flame retardance: the oxygen index (LOI) reaches 34.5% (no flame retardance exists in the prior art); the antibacterial property is that the Escherichia coli inhibition rate is 99.2% (ASTM E2149 standard), and the environmental protection property is that 2.8 tons of limestone can be reduced for each ton of products, and 1.2 tons of CO2 emission can be reduced.

The invention belongs to the technical field of biomedical materials and targeted drug delivery systems, and discloses a targeted controlled-release drug delivery system based on a polymer nano-carrier and a preparation method thereof.The system is of a three-layer structure and comprises a core layer formed by taking polyvinyl alcohol as a matrix and used for efficiently entrapping a drug, and an outer layer formed by taking polyvinyl alcohol as a matrix and used for efficiently entrapping the drug; the shell layer formed by the polylactic acid-glycolic acid copolymer is used for providing structural stability and slow release capability, and the shell layer formed by the polyvinyl alcohol-hydroformylated glucan grafted copolymer is used for realizing microenvironment response release. And the surface of the shell layer is covalently modified with a tumor membrane targeting aptamer and a microenvironment response peptide, so that accurate recognition and local trigger release can be realized. The system has good particle size stability, responsive release ability and tumor cell targeted enrichment effect, and is suitable for efficient delivery and controlled release of various antitumor drugs.

This invention discloses a method for preparing a 3D-printed hydrogel scaffold for cartilage repair, comprising: providing methacrylamide chitosan; providing 2-([1,1-biphenyl]-4-ylcarbamoyl)benzoic acid@polylactic acid-glycolic acid copolymer microspheres; obtaining a 3D-printed bio-ink for cartilage repair using methacrylamide chitosan, 2-([1,1-biphenyl]-4-ylcarbamoyl)benzoic acid@polylactic acid-glycolic acid copolymer microspheres, recombinant collagen CF-1552, and lithium magnesium silicate as main raw materials; and obtaining a 3D-printed bio-ink for cartilage repair using the 3D-printed bio-ink for cartilage repair as a raw material to obtain a 3D-printed hydrogel scaffold for cartilage repair. This 3D-printed hydrogel scaffold has advantages such as antibacterial properties and the ability to promote the differentiation of human bone marrow mesenchymal stem cells (hBMSCs) into chondrocytes, and can be used for cartilage repair, potentially bringing new curative opportunities for cartilage injury diseases.

This invention discloses a biodegradable, highly bioactive magnesium bone particle, its preparation method, and its applications, belonging to the field of biomedical materials technology. Using magnesium bone particles as a matrix, an active composite coating layer comprising biodegradable polymer components and inorganic phase components is formed on its surface to construct biodegradable, highly bioactive magnesium bone particles. The biodegradable polymer components are one or more selected from polycaprolactone, polylactic acid, polylactic-co-glycolic acid copolymer, polyhydroxyalkanoates, chitosan, and their derivatives; the inorganic phase is one or more selected from hydroxyapatite, titanium dioxide, calcium phosphate materials, and combinations thereof. The preparation method includes magnesium bone particle matrix preparation, active composite layer slurry preparation, magnesium bone particle coating, and post-treatment. The prepared biodegradable, highly bioactive magnesium bone particles exhibit good degradation regulation performance and excellent bioactivity, and can be used in bone tissue engineering, bone defect repair, and scaffold filling fields.

The present invention discloses a psoralen mannosylated chitosan polymer nanoparticle and its preparation method and application. The psoralen is composed of psoralen, poly(lactic-co-glycolic acid) copolymer, mannosylated chitosan and polyvinyl alcohol, wherein the mass ratio of psoralen, poly(lactic-co-glycolic acid) copolymer, mannosylated chitosan and polyvinyl alcohol is 2-10:10-30:16.5-38.5:1-9. The psoralen mannosylated chitosan polymer nanoparticle is composed of free psoralen drug and mannosylated chitosan polymer carrier. Compared with traditional psoralen, the psoralen has a more stable structure and better physicochemical properties, and has higher bioavailability and tumor targeting. It can be used as a regulator of tumor-associated macrophages and cytokines, and can also inhibit the growth of MDA-MB-231 breast cancer cells and can be used to prepare a drug for treating triple-negative breast cancer.

The present invention provides a kind of ink with lasting fragrance and preparation method thereof, belong to the field of ink technology, the ink with lasting fragrance comprises the following raw materials in parts by weight: 20-40 parts of tripropylene glycol diacrylate, 10-20 parts of trimethylolpropane triacrylate, 20-50 parts of polyurethane acrylate, 1-5 parts of silicone acrylate, 4-6 parts of photoinitiator, 1-5 parts of active amine co-initiator, 3-5 parts of fragrance sustained-release capsule, 0.3-0.5 parts of defoamer, 5-15 parts of solvent; wherein, the fragrance sustained-release capsule is composed of an oil phase consisting of plant essential oil, polylactic acid-co-glycolic acid copolymer, PCL-PEG grafted cyclodextrin and ethyl acetate, and an aqueous phase consisting of polyvinyl alcohol in water, and is made by high-pressure homogenization, rotary evaporation and drying. The ink fragrance prepared by the present invention lasts for a long time and has the characteristics of good stability, strong adhesion, fast curing, scratch resistance, and green environmental protection.

The invention relates to the technical field of heterocyclic compound drugs and preparation and application thereof, in particular to a tropane alkaloid prodrug composition for treating COPD (chronic obstructive pulmonary disease) and application of the tropane alkaloid prodrug composition. According to the composition, scopane alkaloid, mannose-6-phosphoric acid and a polylactic acid-glycolic acid copolymer are combined, and the prodrug nano composition is constructed through a nanoparticle preparation technology and is used for aerosol inhalation administration. The prodrug composition aims to solve the problems of low bioavailability and lack of targeting in conventional administration of scopolamine alkaloids. Mannose-6-phosphoric acid is introduced into the surfaces of nanoparticles to achieve targeted delivery, enrichment of drugs in the lung is promoted, drug release is controlled through a polylactic acid-glycolic acid copolymer, and the local drug concentration and treatment efficacy of the lung are improved.

The present invention discloses a degradable tissue engineering labrum scaffold and a preparation method thereof. The scaffold uses a degradable polymer and an inorganic component as raw materials. Based on the melt electrostatic spinning process, the molten raw materials are stretched into fibers under the stretching effect of the electric field and the airflow field. The fibers are attached to a receiving roller to obtain highly oriented fiber bundles or fiber membranes. The fiber bundles or fiber membranes are loaded with polylactic-co-glycolic acid (PLGA) microspheres containing the small molecule drug bergenin and transforming growth factor β1 by spraying or soaking. The oriented fiber bundles or oriented fiber membranes after loading are curled to obtain oriented fiber aggregates. The obtained oriented fiber aggregates are placed in a pre-made mold for shaping, and the labrum scaffold is obtained after a period of time. The labrum scaffold prepared by the present invention has the advantages of bionic structure, solvent-free, high strength and good biocompatibility. It imitates the basic structure of the natural labrum composed of highly oriented circumferentially running collagen fiber bundles and has high tensile strength.

The invention relates to an anti-inflammatory and lipid-lowering-based nano preparation for treating fatty liver and a preparation method of the nano preparation. Galactose modified polyethylene glycol-polylactic acid-glycolic acid copolymer (PEG-PLGA) is used as a targeting carrier, and a lipid-lowering drug fenofibrate and an anti-inflammatory drug curcumin are co-loaded; the particle size of the nano preparation is 150-200nm, and the drug encapsulation efficiency is greater than or equal to 85%. Galactose modified PEG-PLGA is adopted as a carrier, galactose can be specifically combined with an asialoglycoprotein receptor (ASGPR) specifically expressed on the surface of liver cells, active targeting of the liver is achieved, the drug enrichment amount of the liver lesion position is remarkably increased, meanwhile, accumulation of drugs in extrahepatic tissue is reduced, extrahepatic toxicity is effectively reduced, and the drug delivery effect is improved. According to the present invention, the anti-inflammatory drug curcumin and the fenofibrate are combined, such that the biological safety of the preparation is improved, the lipid lowering drug fenofibrate and the anti-inflammatory drug curcumin are innovatively co-loaded, and the fenofibrate and the anti-inflammatory drug curcumin form the synergistic effect system: fenofibrate can activate peroxisome proliferator-activated receptor alpha (PPAR alpha), promote liver lipid catabolism, and reduce lipid deposition;

The invention relates to a high-purity hematoporphyrin preparation and a preparation method thereof.The preparation method comprises the steps that S1, hemin and a saturated hydrobromic acid glacial acetic acid solution are mixed and stirred for 15-24 h, and a reaction solution is obtained; s2, adding a sodium hydroxide solution into the reaction solution, and filtering and collecting a first precipitate; s3, dissolving the first precipitate in a hydrochloric acid methanol solution, adding an ammonium carbonate solution after water bath reflux, and filtering and collecting a second precipitate; s4, dissolving the second precipitate in chloroform, enabling the second precipitate to pass through a chromatographic column filled with neutral aluminum oxide, and performing elution by adopting a mixed solution of chloroform and petroleum ether to obtain an eluent; s5, crystallizing; s6, adding the crystals into a sodium hydroxide solution, heating in a water bath, and filtering and collecting a third precipitate; s7, dissolving the third precipitate in water, adding a polylactic acid-glycolic acid copolymer, and filtering and collecting a fourth precipitate; and S8, putting the fourth precipitate and water-soluble nano titanium dioxide into water, stirring, standing, and filtering to obtain filtrate. The impurity content in the hematoporphyrin preparation can be reduced.

Silica nanocarriers hybridized with superparamagnetic iron oxide nanoparticles (“SPIONs”) and curcumin through equilibrium or enforced adsorption technique. Methods for dual delivery of SPIONs and curcumin to a target for diagnosis or therapy, for example, for SPION-based magnetic resonance imaging or for targeted delivery of curcumin to a cell or tissue. The technique can be extend to co-precipitation of mixed metal oxide involving Ni, Mn, Co and Cu oxide. The calcination temperature can be varied from 500-900° C. The nanocombination is functionalized with chitosan, polyacrylic acid, PLGA or another agent to increase its biocompatibility in vivo.

The invention belongs to the technical field of preparation of Milsartan potassium tablets, and particularly relates to a Milsartan potassium tablet and a preparation method thereof. A fumaric acid-sodium citrate composite pH regulator and tartaric acid are adopted to synergistically construct a subacid stable system, and a polylactic acid-glycolic acid copolymer / hydroxy propyl cellulose composite adhesive is combined to enhance the particle formability; a step-by-step process for preparing medicine-containing particles by fluidized bed granulation and preparing medicine-free particles by a wet method is matched with a dodecyl maltoside solubilizing system and a triple lubrication system, and the medicine is formed by drying under reduced pressure after being mixed and tableted. According to the present invention, the obtained tablet has the hydrolysis product increase of only 0.11-0.24% after the acceleration test for 3 months, has the dissolution rate of 93-96% in 30 min, has characteristics of excellent chemical stability and rapid dissolution, and effectively improves the bioavailability and the production feasibility.

The present invention provides compositions comprising peptide-coupled biodegradable poly(lactide-co-glycolide) (PLG) particles. In particular, PLG particles are surface-functionalized to allow for coupling of peptide molecules to the surface of the particles (e.g., for use in eliciting induction of immunological tolerance).

The invention discloses a ginsenoside compound preparation for enhancing human immunity and a preparation method thereof, and belongs to the field of pharmaceutical preparations. The ginsenoside compound preparation comprises the following components in parts by weight: piperonol, NH2-PEG-OH, ginsenoside, poly (lactic-co-glycolic acid) and a surfactant. A coating carrier of ginsenoside is improved, ginsenoside is coated in nano-particles of polylactic acid-glycolic acid, and the outer layers of the nano-particles are coated with piperl modified polyethylene glycol, so that the integrity of ginsenoside in gastric juice can be improved, and an introduced piperl group can effectively inhibit P-gp; the absorbability of the intestinal tract to the ginsenoside is improved, so that the bioavailability of the ginsenoside is improved, and the performance of the ginsenoside to a human body is enhanced.

This invention relates to nanospheres for targeted removal of senescent cells in diabetic wounds and their preparation method. The nanospheres of this invention are galactose-modified PLGA-loaded Fe3O4 nanospheres. Polylactic acid (GAL) is grafted onto the surface of polylactic acid-glycolic acid copolymer (PLGA) microspheres to form a GAL-PLGA complex. Fe3O4 is encapsulated within the complex to form Fe3O4-loaded nanospheres. When the microspheres are engulfed and enter senescent cells in the diabetic wound, they enter lysosomes. Utilizing the increased β-galactosidase activity in senescent cells, the surface GAL can be degraded by the increased activity of β-galactosidase, selectively and slowly releasing the Fe3O4 encapsulated within the microspheres into the senescent cells. The free iron ions generated in the acidic microenvironment of the lysosome induce ferroptosis in the senescent cells, thereby achieving the goal of targeted removal of senescent cells in diabetic wounds.

The application relates to a sustained-release microneedle of water-soluble medicine and a preparation method thereof. The sustained-release microneedle of water-soluble medicine comprises a backing layer and a needle body arranged on the surface of the backing layer, the needle body comprises a needle tip, the material of the needle tip comprises water-soluble medicine and a polymer material, the polymer material comprises a combination of polylactic acid-glycolic acid copolymer with a mass ratio of (80-99):(1-20) and polylactic acid, the polylactic acid-glycolic acid copolymer comprises first polylactic acid-glycolic acid copolymer with a molecular weight of 60kDa-120kDa and second polylactic acid-glycolic acid copolymer with a molecular weight of 10kDa-40kDa, and the mass ratio of the first polylactic acid-glycolic acid copolymer to the second polylactic acid-glycolic acid copolymer is (1-6):1. The sustained-release microneedle can realize the sustained release of water-soluble medicine, avoid burst release, and simultaneously has good needle-forming property and mechanical property.

Disclosed in the present invention are a novel artificial bone based on promoting neurovascular regeneration and a preparation method. The novel artificial bone comprises an artificial bone. The artificial bone is composed of β-tricalcium phosphate, polylactic acid-glycolic acid, a nano magnesium-based powder, and a piezoelectric polymer. The mass ratio of β-tricalcium phosphate to polylactic acid-glycolic acid in the artificial bone is 1:0-1:10. The nano magnesium-based powder and the piezoelectric polymer are mixed to form a piezoelectric composite solution, and the mass ratio of the nano magnesium-based powder to the piezoelectric polymer in the piezoelectric composite solution is 1:1-1:20, such that the surface of the artificial bone is modified by means of the piezoelectric composite solution, thereby forming a piezoelectric coating on the surface of the artificial bone; in this way, when the artificial bone is implanted into a bone defect site and is subject to stress, a charge and potential difference are generated. The present invention not only enhances the strength of the artificial bone, but also promotes the degradation of the artificial bone, stimulates local neurovascular regeneration, promotes the formation of new bone, and achieves the purpose of repairing osteonecrosis and bone defects.