79 results about "Tissue engineering scaffold" patented technology

The preparation method comprises the following steps: (1) fish skin pretreatment: (2) gas foaming treatment: weighing sodium borohydride with a certain molar concentration, dissolving the sodium borohydride in a phosphate buffer solution with a certain concentration, stirring until bubbles in the solution are obviously generated and most of solids are dissolved, and then, carrying out gas foaming treatment; putting the cleaned fish skin tissues in the step (2), and performing foaming treatment; (3) cleaning treatment; and (4) protection and storage. The gas foaming technology is innovatively adopted for decellularization treatment, the interface stripping effect between cells and a matrix is remarkably enhanced on the premise that the collagen three-dimensional structure and the scaffold morphology integrity are not damaged, and the method is suitable for the decellularization pretreatment process of soft tissue (such as fish skin and placenta) with a compact structure or cell-intensive type. The development of a biomedical material, especially a tissue engineering scaffold technology, is promoted, and the preparation method has a wide application prospect.

The invention relates to a chitosan-collagen synergistic self-assembly fiber material and a preparation method thereof, and belongs to the technical field of biological fiber materials. According to the method, the mass ratio of chitosan to collagen is controlled, co-assembly is induced through hydrogen bonds and electrostatic interaction in a low-temperature PBS solution, and then glutaraldehyde crosslinking, gradient dehydration and supercritical drying are performed to prepare the freeze-dried fiber. The obtained material completely retains the triple helix conformation of collagen, and has excellent conformation stability and enzymolysis resistance. The mechanical strength of the composite fiber is remarkably improved, and the composite fiber has excellent antibacterial property and cell affinity. The process does not need a toxic cross-linking agent, the operation is simple and convenient, and the prepared fiber is suitable for the high-end biomedical fields of tissue engineering scaffolds, intelligent antibacterial dressings, degradable nerve conduits and the like.

A method for preparing a magnesium alloy tissue engineering scaffold with a smooth inner surface by laser powder bed fusion (LPBF) is provided. The method includes: step S1: scanning a porous scaffold, and selecting the densest filling scan parameters, where the scanning includes a single-pass contour scan and a single-pass filling scan; step S2: optimizing a contour scan strategy according to the densest filling scan parameters; step S3: acquiring a corresponding melt pool dimension, and adjusting a spot compensation value based on the optimized contour scan strategy; and step S4: preparing a magnesium alloy tissue engineering scaffold based on the contour scan strategy and the adjusted spot compensation value. The method eliminates powder adhesion and sagging defects inside the complex porous structure that severely affect inner surface roughness and scaffold performance, thereby the pore connection, fatigue and corrosion resistance will be improved greatly.

The application provides a preparation method of a long-size, high-consistency and high-strength hydrogel, adopts a preparation process of directional constant-speed freezing combined with freezing cross-linking, first injects a raw material solution into a mold, then vertically immerses the mold into a cold source at a constant speed to realize directional growth of ice crystals, controls consistency and stability of the ice crystal structure, puts the directional ice crystal template into a low-temperature cross-linking system after freezing is completed, uniformly heats the system in the cross-linking process to further fix the channel structure, and finally obtains a hydrogel product with good mechanical properties and an anisotropic structure. The preparation method provided by the application can be suitable for various polymer systems, can be extended to preparation of large-size tissue engineering scaffolds and other materials, and has excellent popularization value.

The application provides a biocompatible biological aerogel material and a preparation method thereof, and the method comprises the following steps: cleaning and roughening pretreatment of a substrate; dissolving polyvinyl alcohol to prepare a precursor solution; introducing wear-resistant reinforcing materials into the precursor solution and uniformly dispersing the wear-resistant reinforcing materials; adding a crosslinking agent, glutaraldehyde, to perform a crosslinking reaction and construct a three-dimensional network structure; coating the system in the initial stage of crosslinking on the substrate, and performing low-temperature or freeze-drying and subsequent heat treatment to form a stable coating. The obtained material takes polyvinyl alcohol as a biocompatible skeleton, and has excellent porous structure, mechanical properties and wet stability through chemical crosslinking and reinforcing phase compounding. In-vitro cell experiments show that the material has no obvious toxicity to cells, and the cells adhere and spread well. The application solves the problem that the existing biological aerogel material is difficult to consider the biocompatibility, structural stability and process friendliness, and is suitable for the biomedical field such as tissue engineering scaffolds and wound dressings.

The invention provides PVDF / gelatin / CNF composite hydrogel capable of enhancing piezoelectric property based on an in-situ stretching effect and a preparation method and application thereof. According to the composite hydrogel, multi-directional constraining force is applied to a PVDF molecular chain through reaction among CN, multivalent metal ions in a cross-linking agent and PVDF; and the in-situ stretching polarization is realized by promoting the transformation from a non-piezoelectric alpha / gamma phase to a piezoelectric beta phase with an all-trans conformation. The composite hydrogel has good biocompatibility, degradability, high strength, high toughness and fatigue resistance, is mild in preparation condition and low in energy consumption, and has huge application potential in the fields of wearable stress / strain sensors, self-powered implantable medical equipment, high-performance energy collectors, bearing tissue engineering scaffolds and the like.

The invention provides an enzyme-residue-free extracellular matrix microsphere as well as a preparation method and application thereof. An elutable sacrificial phase material capable of being subjected to liquid-liquid phase separation with an extracellular matrix is introduced in an extracellular matrix pelletizing process, and transglutaminase is confined in a sacrificial phase, so that the extracellular matrix microsphere is prepared. And the transglutaminase and the extracellular matrix form a spatially separated structure in the balling process. In the gel forming stage, transglutaminase catalyzes protein in an extracellular matrix on a two-phase interface to generate a cross-linking reaction, and microspheres with a three-dimensional network gel structure are formed; after cross-linking is completed, transglutaminase is removed by eluting the sacrificial phase material, and meanwhile, a porous network with a communicated structure is formed in situ in the microsphere, so that the obtained extracellular matrix microsphere still keeps good structural integrity and mechanical property while realizing no residue of enzyme with catalytic activity; the scaffold can provide stable support for cell adhesion, migration and three-dimensional culture, and is applicable to cell delivery, organoid construction, tissue engineering scaffolds and the like.

The invention provides a porous tissue engineering scaffold with a drug controlled release function as well as preparation and application of the porous tissue engineering scaffold. The preparation method of the porous tissue engineering scaffold comprises the following steps: S1) preparing double-layer nanoparticles by PLGA-PEG; and S2) preparing a composite scaffold by a low-temperature 3D printing technology. The stent prepared by the method has efficient drug controlled release capability, excellent mechanical properties, good biocompatibility and controllable degradation. The optimized porous structure promotes cell proliferation and tissue regeneration, meanwhile, low-temperature printing keeps the stability and activity of materials and drugs, and the material is widely applied to the fields of bone tissue engineering, local drug delivery and the like and shows remarkable clinical application value and market potential.

This invention provides a biomimetic periodontal complex multilayer hydrogel tissue engineering scaffold, its preparation method, and its application, relating to the technical field of tissue engineering scaffolds. The biomimetic periodontal complex multilayer hydrogel tissue engineering scaffold comprises, from the inside out, a cementum repair layer, a periodontal ligament repair layer, and an alveolar bone repair layer; the cementum repair layer and the alveolar bone repair layer include a mineralized hydrogel layer; wherein the raw materials for preparing the mineralized hydrogel layer include modified hyaluronic acid, methacrylamide type I collagen, and hydroxyapatite; the alveolar bone repair layer includes a non-mineralized hydrogel layer; wherein the raw materials for preparing the non-mineralized hydrogel layer include modified hyaluronic acid, methacrylamide type I collagen, and fibrin I. This invention precisely matches the mechanical and biological requirements of each layer of the periodontal complex through a three-layer structure, a reversibly hydrazone-regulated viscoelastic gradient, and a differentiated biochemical microenvironment of nHAp / FBN1.

This invention relates to the field of biomedical materials technology, and more particularly to a method for preparing a hydroxyapatite bone tissue engineering scaffold, comprising the following steps: preparing acetylated or alkylated modified cellulose nanocrystals; using the modified cellulose nanocrystals as a biodispersant to synthesize hydroxyapatite; and using the synthesized hydroxyapatite to prepare a bone tissue engineering scaffold. The preparation method of this invention is simple, requires minimal experimental conditions, and does not require expensive equipment; it also does not introduce organic surfactants, and the dispersant used is essentially harmless to the environment and organisms; the prepared HA exhibits good dispersibility; and the hydroxyapatite bone tissue engineering scaffold has good biocompatibility, which is beneficial for osteoblast proliferation and differentiation, and for the structural remodeling and construction of bone defect tissue.

The invention discloses a protein controllable self-assembly-based mild universal hydrogel toughening method, which is characterized in that more rigid and hydrophobic beta-folded ordered stacking structures are formed by controlling the transformation of protein macromolecular structures, and the mechanical properties of protein-based hydrogel are enhanced by cooperating with ionic physical cross-linking immobilization; through the synergistic effect of a physical network and a chemical network, the toughness, the strength, the elasticity and the anti-fatigue property of the hydrogel are remarkably improved under a completely mild condition. The method does not need toxic cross-linking agents or violent reaction conditions, has wide selectivity, is suitable for various protein raw materials, and opens up a new way for preparing the protein-based tough hydrogel, and the prepared hydrogel has wide application prospects in the fields of flexible sensors, tissue engineering scaffolds, drug sustained-release carriers, wound dressings or environmental engineering and the like.

The invention belongs to the technical field of tissue engineering scaffolds, and relates to a micro-nano fiber patterned tissue engineering scaffold and a solution electrostatic spinning preparation method thereof, and the micro-nano fiber patterned tissue engineering scaffold is formed by randomly interlacing and compounding uniformly distributed micron-scale skeleton fibers and nano-scale filling fibers on a patterned receiving electrode, the diameter of the micron-scale framework fiber is 15-25 microns, and the diameter of the nano-scale filling fiber is 200-500 nm; the nano-scale filling fibers are distributed on the surfaces of the micron-scale skeleton fibers and among different micron-scale skeleton fibers, and the micron-scale skeleton fibers and the nano-scale filling fibers penetrate through each other to form a three-dimensional graded fiber network structure; the patterned receiving electrode is of a three-layer structure; during preparation, a spinning solution A and a spinning solution B are prepared respectively, the patterned receiving electrode is used as a receiving device, and the micro-nano fiber patterned tissue engineering scaffold is prepared by spraying the solutions through double nozzles for electrostatic spinning. The product provided by the invention can be better matched with the mechanical behavior of a target organization; the preparation method is simple.

The invention discloses an electrostatic spinning nanofiber membrane for promoting jawbone defect osteogenesis and a preparation method, relates to the technical field of medical tissue engineering materials, and aims to solve the problem that a tissue engineering scaffold applied to periodontal tissue regeneration is mostly soaked in a solution, and the physical loading mode is not beneficial to long-term stable release of growth factors. In the prior art, metal ions are often used for activating osteoblasts, but the activation effect is limited, so that the metal ions are difficult to promote the regeneration of periodontal tissues because the metal ions are difficult to fully mobilize the initiative of the cells. The invention provides an electrostatic spinning nanofiber membrane for promoting jaw defect osteogenesis and a preparation method thereof. The preparation method comprises the following steps: preparing freeze-dried CGF powder; preparing a PVA / SA / nHA solution, and adding the freeze-dried CGF powder to obtain a spinning solution; and collecting the spinning solution on an aluminum foil roller to obtain the PVA / SA / CGF / nHA electrostatic spinning nanofiber membrane. Concentrated growth factors can be continuously and stably released, and osteogenic differentiation of peripheral jawbones is promoted.

The invention discloses a degradable macroporous composite tissue engineering scaffold, a structural performance regulation and control method and application, and belongs to the technical field of biomedical materials. Induced phase separation is realized through design of gel molecules and a solvent, so that a macroporous structure is formed; the pore structure is adjusted by controlling the proportion of the polyvinyl alcohol aqueous solution, the glycerol and the hydrophilic degradable biomacromolecule aqueous solution; the mechanical property of the stent is regulated and controlled by adding the degradable inorganic micro-nano particles; meanwhile, a pore structure and a scaffold material with spatial heterogeneity in mechanical property are constructed through hot melt interface integration. The problems that an existing tissue engineering scaffold is insufficient in controllability of a pore structure and mechanical properties and the like are solved, and the degradable macroporous composite tissue engineering scaffold material is suitable for being used as a degradable macroporous composite tissue engineering scaffold material for promoting collaborative injury repair of soft and hard tissues such as osteochondral tissues, muscular bones and tendon bones.

The application relates to the technical field of medical materials, in particular to an antioxidant and bacteriostatic chitosan hydrogel and a preparation method thereof. The method is characterized in that lipoic acid is first grafted on a chitosan molecular chain to prepare modified chitosan; then the modified chitosan is mixed with a functional additive, a photo irradiation is performed to initiate ring-opening crosslinking of a lipoic acid disulfide five-membered ring, meanwhile, a mercapto-dithiol exchange reaction occurs between mercapto groups on the surface of the functional additive and a disulfide bond, and a three-dimensional network hydrogel is rapidly formed; the functional additive is prepared through ultraviolet light reaction of mercapto titanium oxide microspheres, a synergistic bacteriostatic agent and a modifier, and a three-dimensional bacteriostatic network layer is formed on the surface of the titanium oxide microspheres; the chitosan hydrogel prepared by the method has excellent antibacterial performance and good antioxidant performance, is suitable for the biomedical field such as wound dressings, tissue engineering scaffolds and drug sustained-release carriers, and has a wide application prospect.

The invention belongs to the technical field of biology, and particularly relates to a corneal nerve bionic guiding support based on an electrospinning technology. The corneal nerve bionic guide stent provided by the invention is high in porosity and beneficial to cell attachment, migration and neurite extension, and during use, the stent structure can simulate the arrangement direction of corneal nerves, can effectively guide nerve axons to grow in a specific direction, and improves the nerve regeneration efficiency; according to the invention, the silk fibroin is compositely modified by adopting a plurality of growth factors such as NGF, NT-3, NT-4 / 5, NPY and VEGF, so that a multi-factor synergistic effect is realized, and related signal channels of nerve regeneration can be more comprehensively activated. After the polycaprolactone and the silk fibroin are compounded, complementary advantages are formed, the structural strength requirement of the cornea tissue engineering scaffold is met, good flexibility is kept, and the scaffold has good cell affinity and tissue integration capacity and is suitable for tissue engineering scaffolds.

The present application relates to the field of biomimetic mineralization and tissue engineering scaffold materials, and particularly relates to a kind of biomimetic mineralization silk fibroin scaffold material and its preparation method and application.The preparation method comprises the following steps:1) silk fibroin is induced self-assembly, and silk fibroin fiber matrix is obtained;2) the silk fibroin fiber obtained in step 1) is crosslinked, and crosslinked silk fibroin fiber mineralization matrix is obtained;3) the crosslinked silk fibroin fiber mineralization matrix obtained in step 2) is mineralized in mineralization solution, and biomimetic mineralization silk fibroin scaffold material is obtained.The biomimetic mineralization silk fibroin scaffold material prepared by the preparation method is applied to bone tissue repair.In the present application, the mineralization mode in silk fibroin fiber more highly simulates the mineralization form of natural bone tissue, and the similar surface chemical properties and nano-scale structure characteristics of natural bone are reproduced.

The invention discloses a preparation method and application of IBFO (at) high-entropy alloy heterojunction piezoelectric hydrogel (IBHA-SAPS), and the preparation method comprises the following steps: preparing high-entropy alloy (HEA) powder through sol-gel and calcination, compounding the HEA powder with bismuth-doped bismuth ferrite (IBFO) to construct an IBFO (at) HEA heterojunction (IBHA), and finally carrying out cross-linking molding with a sodium alginate-phenylboronic acid polymer. Under ultrasonic stimulation, the piezoelectric effect of the hydrogel can synergistically enhance the sonodynamic performance and the nano-enzyme activity, and in an acidic microenvironment, efficient antibiosis and biological membrane removal can be achieved through high-intensity ultrasound; in a neutral physiological microenvironment, low-intensity ultrasound can trigger the composite material to remove active oxygen so as to relieve oxidative stress and generate an electric signal to promote osteoblast differentiation, and the composite material has good biocompatibility, injectability and intelligent responsiveness and has wide application prospects in the fields of sonodynamic therapy, tissue engineering scaffolds, infectious bone defect repair and the like.

The invention relates to the technical field of biological tissue engineering scaffolds, in particular to a whole intervertebral disc decellularized tissue engineering scaffold as well as a preparation method and application thereof. The method comprises the following steps: taking an intervertebral disc-bone complex of a vertebrate as a sample, and sequentially carrying out surface polishing treatment, degreasing treatment and cryopreservation rewarming treatment on the sample to obtain a pretreated sample; placing the pretreated sample in a Tris-HCl buffer solution containing a surfactant and a protease inhibitor, and carrying out oscillation treatment; putting the sample subjected to oscillation treatment into a decellularization solution, and carrying out decellularization treatment; putting the sample subjected to the decellularization treatment into a nuclease buffer solution, and carrying out nuclease treatment; and sequentially washing and freeze-drying the nuclease treated sample to obtain the whole intervertebral disc decellularized tissue engineering scaffold. Most of cell components and genetic materials are removed from the scaffold, a relatively complete extracellular matrix structure and mechanical properties are reserved, and the scaffold can be applied to the field of intervertebral disc repair and regenerative medicine.

The invention belongs to the technical field of preparation of tissue engineering scaffolds, and discloses a flexible composite scaffold based on digital light printing polycaprolactone and a surface coating and a preparation method of the flexible composite scaffold. The flexible composite scaffold with the surface coating comprises a polycaprolactone skeleton, and a silk fibroin film layer and the surface coating which are sequentially positioned on the skeleton from inside to outside, the surface coating is a modified layer of functional molecules, and the functional molecules simultaneously comprise PEGDA, GelMA and RGDMA. According to the invention, a polycaprolactone three-dimensional skeleton printed by a digital light processing technology is used as a configuration support frame, the outer layer of the polycaprolactone three-dimensional skeleton is coated with a silk fibroin film, and the surface of the silk fibroin film is modified with functional molecules, so that the composite scaffold which is programmable in shape, adjustable in mechanical property and has biological activity is realized through a collaborative construction mode; the method is suitable for various tissue engineering application fields such as bone repair, valve regeneration and soft tissue repair, and has excellent application prospect and popularization value.

The embodiment of the application discloses a preparation method of humanized extracellular matrix, and belongs to the technical field of biomedical materials and tissue engineering. The method comprises the following steps: preparing human decellularized dermal matrix; preparing a concentrated solution of a condition medium rich in human active factors; constructing RGD-PLGA / BMP-2 nanocomposites; loading the concentrated solution of the condition medium into the human decellularized dermal matrix through vacuum negative pressure perfusion, and then anchoring the RGD-PLGA / BMP-2 nanocomposites, and cross-linking them twice through genipin to obtain the humanized extracellular matrix. Through the four-element strategy of decellularized matrix-active factor-nano-sustained release-two-stage cross-linking, the unity of low immunogenicity, high biological activity and spatiotemporal controllable release function is realized, and the humanized extracellular matrix can be applied to the fields of tissue engineering scaffolds, wound repair and bone defect filling.

The invention belongs to the field of biomedical engineering materials, and aims to provide a biodegradable bone repair material capable of 3D printing and a preparation method thereof. Biological 3D printing is an emerging subject of additive manufacturing and biomedicine cross fusion, and the tissue engineering scaffold obtained through biological 3D printing has good biocompatibility and excellent biological activity. The degradable bone repair material and 3D printing are combined. Degradable polylactic acid and an inorganic biological material are fused, polycaprolactone-ZnO is subjected to electrostatic spinning to enhance the supporting strength of the material, and meanwhile hydroxyapatite and trace metal elements needed by bone tissue growth are added. In clinical application, the bone repair material plays a supporting role in cell division and new tissue generation. In clinical application, the bone repair material plays a supporting role in cell division and new tissue generation. Along with gradual degradation of the repair material in a living body, the degradation product does not generate host reaction to the living body, and meanwhile, secondary trauma and medical cost caused by the fact that a patient needs to carry out a secondary operation to take out an implant material after bone repair are reduced.

The invention provides an antibacterial nickel-titanium alloy bone tissue engineering scaffold as well as a preparation method and application thereof. The preparation method comprises the following steps: polishing a nickel-titanium alloy sheet; carrying out acid etching treatment on the nickel-titanium alloy sheet subjected to the polishing treatment; then adopting glutaraldehyde crosslinking to introduce a chitosan coating; and introducing a sodium alginate coating and a chitosan quaternary ammonium salt coating to prepare the antibacterial nickel-titanium alloy bone tissue engineering scaffold. According to the antibacterial nickel-titanium alloy bone tissue engineering scaffold, the chitosan quaternary ammonium salt coating is formed on the surface of the nickel-titanium alloy in a layer-by-layer self-assembly mode, the tissue compatibility of the nickel-titanium alloy can be effectively improved, the antibacterial activity is good, the osteogenic activity of osteoblasts can be enhanced, proliferation of the osteoblasts is facilitated, and the bone tissue engineering scaffold has a good application prospect. And the material can be widely applied to bone substitute materials.

The application discloses a preparation method of a multi-phase "core-shell" biomimetic tissue engineering support, and constructs a multi-phase "core-shell" in-situ biomimetic support to promote the reconstruction of a rotator cuff tendon-bone interface; the support is made of PCL / PEO biological materials and mixed with a plurality of bioactive factor microspheres, the support fiber is a "core-shell" structure, the "shell" contains SDF-1 chitosan slow-release microspheres, the "inner core" is a bone tissue layer, a fibrocartilage layer and a tendon layer, the layers are continuously printed, the spatial distribution of various factors is fine and controllable, the tendon-bone interface is reconstructed in a biomimetic manner, the sequential controllable release of SDF-1 in the outer layer and various differentiation induction factors in the inner core is realized by using the "core-shell" structure fiber, the endogenous MSCs recruitment and the ordered directional differentiation of each layer are promoted, and the application develops an electrohydrodynamic coaxial 3D printing technology on the basis of the electrohydrodynamic printing technology, and constructs a multi-phase "core-shell" in-situ biomimetic support to promote the reconstruction of the rotator cuff tendon-bone interface.

According to the gas-liquid double-channel hollow fiber perfusion culture system and method, a gas exchange module comprises a plurality of hollow fiber oxygenation membranes, gas channels are formed in the hollow fiber oxygenation membranes, the outsides of the hollow fiber oxygenation membranes are in direct contact with a tissue engineering scaffold culture solution, and dissolved oxygen transmission is achieved through diffusion; the liquid perfusion module comprises a plurality of hollow hemodialysis membranes, culture solution channels are formed in the hollow hemodialysis membranes, the exteriors of the hollow hemodialysis membranes are in direct contact with a tissue engineering scaffold culture solution, and nutrient substance transmission is achieved through diffusion; the monitoring module is used for monitoring key parameters of a tissue engineering scaffold culture solution in real time and can automatically feed back and adjust the gas flow and the liquid flow rate according to monitored data, and the gas-liquid double-channel hollow fiber perfusion culture system has the oxygen supply capacity and the three-dimensional perfusion function; the survival rate and functional expression of cells in the scaffold can be improved, and the stability of a tissue structure can be maintained in vitro for a long time.

This application relates to an in-situ printing device and method for tissue engineering scaffolds. The device includes a main unit, a handheld end, and connecting cables. The main unit includes a housing, a display screen, a control system, and a high-voltage generator. The handheld end includes a body, a propulsion mechanism, and a long nozzle tube. The long nozzle tube is installed at the front end of the main unit, and the high-voltage generator is used to generate a high-voltage electric field at the front end of the long nozzle tube. The propulsion mechanism is installed inside the main unit, and a material tube for storing bio-ink is installed inside the main unit. The propulsion mechanism is connected to both the long nozzle tube and the material tube. The control system controls the propulsion mechanism to deliver the bio-ink to the long nozzle tube, and under the action of the high-voltage electric field, the bio-ink forms fibers and deposits on the area to be repaired to construct a tissue engineering scaffold. This application combines the handheld end with the main unit, and through the main unit controlling the long nozzle tube, directly forms a tissue engineering scaffold in situ inside the body, making the morphology and structure of the scaffold highly match the damaged tissue, reducing surgical risks and patient suffering.

The invention relates to photocuring bio-ink as well as a preparation method and application thereof, and belongs to the technical field of biological materials and tissue engineering. The photocuring bio-ink comprises methacrylated fish scale gelatin and a photoinitiator, the methacrylated fish scale gelatin is prepared from fish scale gelatin and methacrylic anhydride through an acylation reaction, and the substitution degree of the methacrylated fish scale gelatin is 30%-55%. The photocuring bio-ink has the advantages of fast photocuring, low immunogenicity, low fat content and excellent biocompatibility, and is especially suitable for 3D biological printing construction of fine tissue engineering scaffolds and organoids such as cartilage, skin and blood vessels.

The invention discloses a three-layer artificial soft tissue repair membrane with progressively-changed porosity in the field of biomedical tissue engineering, and the repair membrane sequentially comprises an ordered fiber layer, a spiral disordered fiber layer and an ordered fiber layer from inside to outside to form a structure with progressively-increased porosity. Each layer is made of biodegradable materials which can be selected from various natural or synthetic polymers. The diameter of the fiber is in a range from nanoscale to micron scale, and the distance between the fibers of the ordered fiber layer is adjustable and is gradually increased from inside to outside. The membrane can load various bioactive substances and drugs, and the surface of the membrane can also be modified by growth factors or nano materials and the like. The preparation method mainly adopts a near-field direct-writing 3D printing process and is realized by regulating and controlling printing parameters. The obtained repair membrane is unique in pore structure, can simulate natural tissues and promote cell ordered growth and tissue repair, and is suitable for the field of tissue engineering scaffolds.

According to the hydroxyethyl chitosan-polyethylene glycol-laponite composite hydrogel provided by the invention, polyethylene glycol, polyethylene glycol and laponite (LAPONITE) are introduced to form a mixed solution, and the prepared composite hydrogel is uniform and has good stability and mechanical properties; the compound can be clinically used as a tissue filling agent, a tissue engineering scaffold, a drug carrier, a sealing agent or an embolization agent.

The application relates to a preparation method of a tissue-adhesive hydrogel and application thereof, and belongs to the technical field of biological medicines, and solves the technical problems of poor biocompatibility, complex preparation process and difficult preservation of the tissue-adhesive hydrogel, and the solution is as follows: gelatin and casein are crosslinked by a glutamine transferase to form a hydrogel; a layer of chitosan solution is coated on an ex vivo pigskin, and then the hydrogel is covered on the ex vivo pigskin, so that the hydrogel and the ex vivo pigskin are finally adhered together. The tissue-adhesive hydrogel prepared by the application has good biocompatibility and degradability, and has the performances of transparency, water retention, anti-freezing, drug loading and local adhesion with tissues. The natural hydrogel with excellent performances has practical significance and can be applied to the fields of tissue engineering scaffolds, skin dressings, biosensors and the like.