Injectable short-fiber-based hydrogel tissue repair material with electric response characteristic as well as preparation method and application of injectable short-fiber-based hydrogel tissue repair material

Abstract

The invention provides an injectable short-fiber-based hydrogel tissue repair material with an electric response characteristic as well as a preparation method and application thereof, and the injectable short-fiber-based hydrogel tissue repair material with the electric response characteristic is prepared by taking a natural polymer material loaded with bioactive factors as a core layer material and a biodegradable material as a shell layer material through a coaxial electrostatic spinning technology. The method comprises the following steps: preparing short fibers with a core-shell structure, uniformly mixing the short fibers with a hydrogel matrix, injecting and filling a tissue defect part, and carrying out ultraviolet curing to form the tissue repair material. The injectable short-fiber-based hydrogel tissue repair material with the electrical response characteristic provided by the invention has piezoelectric characteristic and injectable characteristic, can generate electrical response through mechanical stimulation so as to promote cell proliferation and tissue repair, and also has controllable drug release capacity and good mechanical adaptability; the method is suitable for application scenes of complex tissue damage repair such as diabetes infected wound repair, articular cartilage repair, oral barrier membrane repair, abdominal wall defect repair and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of surgical biomedical materials, and more specifically, to an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties, a preparation method thereof, and an application thereof. Background Art

[0002] With the development of biomedical materials, hydrogels have been widely used in the fields of tissue engineering, wound repair, and drug delivery due to their high water content, three-dimensional network structure mimicking the extracellular matrix, and excellent biocompatibility. Among them, injectable hydrogels have shown unique value in clinical scenarios such as diabetic chronic wound repair, articular cartilage defect regeneration, oral mucosal barrier reconstruction, and abdominal wall hernia repair due to their minimally invasive implantation characteristics, ability to precisely fill complex defect morphologies, and advantages of photo / thermal-responsive in-situ curing. However, with the upgrading of the functional requirements for repair materials in regenerative medicine, the inherent defects of traditional hydrogels in terms of mechanical adaptability, electrophysiological activity, and drug controlled-release accuracy have become increasingly prominent, severely restricting their in-depth application in dynamic stress environments or electro-sensitive tissue repair.

[0003] Specifically, due to the single cross-linked network structure, the supporting force of the polymer network possessed by traditional hydrogels is limited, their mechanical strength is low, they are prone to degradation or collapse, and it is difficult to maintain a stable repair environment in parts subjected to large forces. Secondly, bioelectric signals are the core regulatory factors for tissue development and repair. During the skin wound healing process, the endogenous electric field generated at the wound edge can guide the directional migration of keratinocytes; the bioelectric signals generated by the piezoelectric effect when bone tissue is stressed can also directly stimulate the activity of osteoblasts. However, traditional hydrogels lack conductive components or piezoelectric structures, cannot simulate this electrophysiological property, and cannot convert mechanical stimuli into electric signals, limiting their regulatory ability in the regeneration of electro-sensitive tissues such as nerve regeneration and myocardial repair. Moreover, since the drug delivery efficacy of hydrogels is limited by the uncontrollability of their swelling kinetics and degradation behavior, the drug controlled-release accuracy of the hydrogel drug system prepared by the traditional embedding method is insufficient, and phenomena such as drug burst release or release lag often occur, making it difficult to maintain an effective concentration and severely affecting the persistence and stability of the tissue repair effect.

[0004] Therefore, it is necessary to develop a tissue repair material of a hydrogel system that takes into account the coordinated optimization of mechanical adaptability, electro-responsive properties, and spatio-temporal controlled release of drugs. Summary of the Invention

[0005] The object of the present invention is to overcome the deficiencies in the prior art and provide a preparation method and an application of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a method for preparing an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties, comprising the following steps: (1) Mix a bioactive factor with a natural polymer material solution evenly to form a core layer solution, dissolve a biodegradable material to form a shell layer solution, and further use a coaxial electrospinning process to prepare a fiber material with a core-shell structure using the core layer solution and the shell layer solution; (2) Subject the fiber material obtained in step (1) to cryosectioning, ultrasonic fragmentation, or mechanical shearing treatment to obtain short fibers; (3) Dissolve and mix a hydrogel matrix and a photoinitiator evenly to form a hydrogel precursor solution; mix the short fibers in step (2) with the hydrogel precursor solution evenly to form a pre-gel solution; (4) Fill the pre-gel solution obtained in step (3) into the tissue defect site and use a photo-curing process to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties; In step (1), the natural polymer material is one or more combinations of chitosan, gelatin, or hyaluronic acid; The biodegradable material is one or more combinations of poly(β-hydroxybutyrate-co-valerate), poly(L-lactic acid), polycaprolactone, or poly(lactic-co-glycolic acid).

[0007] In this technical solution, by integrating the core-shell fiber structure, short fiber reinforcement technology, and photo-cured hydrogel system, an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties is prepared. By combining the short fibers with the core-shell structure with the hydrogel matrix, a multifunctional synergistic composite hydrogel system is formed; specifically, the mechanical properties of the composite hydrogel system are improved by fiber-based reinforcement, and the piezoelectric properties of the fiber material itself and the polarization effect of the core-shell structure can be utilized. At the same time, combined with the charge transfer and electric field enhancement effects generated by the short fiber-based and hydrogel matrix, a piezoelectric effect is generated in the composite hydrogel system, and microelectrical signals can be generated by mechanical stimulation to promote cell proliferation and tissue repair; at the same time, the combination of the core-shell structure short fibers loaded with bioactive factors and the hydrogel composite material can also achieve the controllable release of bioactive components, further improving the therapeutic effect of the composite hydrogel system as a tissue repair material.

[0008] Specifically, in the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties, short fibers truncated by physical methods such as cryosectioning, ultrasonic fragmentation, or mechanical shearing form a three-dimensional network interpenetrating structure in the hydrogel, enabling the composite hydrogel system to possess more excellent mechanical properties. Secondly, natural polymer materials such as chitosan, gelatin, and hyaluronic acid are utilized for their excellent biocompatibility and cell adhesion, and can efficiently load bioactive factors. Subsequently, through coaxial electrospinning technology, the natural polymer material loaded with bioactive factors forms a core layer, and at the same time, biodegradable materials such as poly(β-hydroxybutyrate-co-valerate), poly-L-lactic acid, polycaprolactone, and poly(lactic-co-glycolic acid) are used to form a shell layer to wrap the core layer loaded with bioactive factors. By regulating the degradation rate of the biodegradable material, the inactivation caused by the direct exposure of bioactive factors is avoided, and the sustained release of bioactive factors is achieved, avoiding the burst release effect and matching the tissue repair process. Further, the intrinsic piezoelectricity of the short fiber-based material and the interfacial polarization effect generated between the core layer and the shell layer endow it with good piezoelectric properties. At the same time, the high electric field stretching during the electrospinning process can also change some material properties of the short fiber material, thereby enhancing its piezoelectricity. When the short fiber-based material is uniformly distributed in the conductive hydrogel system, the short fiber-based composite hydrogel system also exhibits a corresponding piezoelectric effect, endowing the material with the ability to undergo conformational changes under electrical stimulation, which can directionally guide cell migration, promote cell proliferation, and tissue repair. Further, through the dynamic physical interaction between the short fiber-based and the hydrogel matrix, the short fiber-based composite hydrogel system has a good shear thinning effect, enabling the pre-gel solution mixed with short fibers to be injected through a needle, thus being suitable for filling and repairing complex anatomical sites such as joint cavities, improving the application performance of the short fiber-based composite hydrogel system as a tissue repair material. At the same time, the photocuring process enables the pre-gel solution mixed with short fibers to achieve in-situ forming, with a simple process and avoiding the cytotoxicity risk of traditional chemical crosslinking.

[0009] Further, the bioactive factor is one or more combinations of curcumin, chondroitin sulfate, or resveratrol. Specifically, curcumin reduces inflammatory factors by inhibiting the NF-κB pathway and simultaneously scavenges free radicals; chondroitin sulfate targets the supplementation of cartilage matrix, promotes the synthesis of type II collagen, and inhibits the activity of matrix metalloproteinase MMP-13; resveratrol activates the SIRT1 pathway, enhances the migration ability of vascular endothelial cells and the activity of antioxidant enzymes, thereby respectively achieving the therapeutic effects of anti-inflammation, matrix reconstruction, and vascularization regulation, and can precisely act on application scenarios such as the repair of complex defective tissues such as diabetic chronic wound repair, articular cartilage defect regeneration, oral mucosal barrier reconstruction, and abdominal wall hernia repair through directional regulation or synergistic effects.

[0010] Further, the process parameters of the coaxial electrospinning are as follows: the rotational speed of the drum collector is 100 - 1500 rpm, the voltage is 10 - 20 kV, the injection speed is 0.1 - 2.0 mL / h, and the annealing treatment temperature is room temperature - 80 °C.

[0011] Further, in step (2), when preparing short fibers by cryosectioning, the fibrous material with a core - shell structure needs to be wrapped by cryo - embedding before sectioning, and the temperature of cryo - embedding is - 80 °C. The embedding reagent is a water - soluble cryo - embedding medium, including but not limited to polyethylene glycol (PEG), polyvinyl alcohol (PVA), etc.

[0012] Further, in step (2), when preparing short fibers by ultrasonic fragmentation, the power of ultrasonic fragmentation is 50 - 200 W, and the time is 0.5 h - 3 h.

[0013] Further, the size of the short fibers is preferably 25 - 100 µm.

[0014] Further, the hydrogel matrix is a combination of one or more of methacrylated gelatin, methacrylated hyaluronic acid, or methacrylated silk fibroin.

[0015] Further, the photoinitiator includes but not limited to one or more of 2 - hydroxy - 4'-(2 - hydroxyethoxy)-2 - methylpropiophenone, lithium acylphosphonyloxy ester, 2,4,6 - trimethylbenzoyl - diphenylphosphine oxide, or 2 - hydroxy - 2 - methyl - 1 - phenyl - 1 - propanone, and its addition amount is preferably 0.5 wt‰ - 1 wt‰.

[0016] Further, in step (4), the photocuring process is as follows: irradiate the part filled with the pre - gel solution with ultraviolet light, and the irradiation time is 5 - 30 min.

[0017] Another object of the present technical solution is to provide an injectable short - fiber - based hydrogel tissue repair material with electro - response characteristics prepared by the preparation method described in the present technical solution; the prepared injectable short - fiber - based hydrogel tissue repair material with electro - response characteristics has injectability, in - situ forming characteristics, and electro - response characteristics during actual use; it not only has good mechanical properties, but also can generate micro - electrical signals when applied to the wound surface through the piezoelectric effect generated, promoting cell proliferation and tissue repair; at the same time, the combination of the core - shell structure short fibers loaded with bioactive factors and the hydrogel composite material can also realize the controllable release of bioactive components, better conforming to the repair process of complex tissue injuries and further improving the therapeutic effect of the composite hydrogel as a tissue injury repair material.

[0018] Another object of the present technical solution is to provide an application of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties in tissue repair materials for dealing with complex tissue injuries such as diabetic infected wound repair, articular cartilage repair, oral barrier membrane repair, abdominal wall defect repair, etc.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The injectable short fiber-based hydrogel tissue repair material with electro-responsive properties provided by the present invention generates certain electro-responsive properties through the synergistic effect of the short fiber-based and the hydrogel matrix, and generates weak electrical signals under mechanical stimulation through the piezoelectric effect, which can effectively promote cell proliferation and accelerate tissue repair. Different from traditional non-electroactive hydrogel materials, it improves the biological activity and tissue repair efficiency.

[0020] (2) Through the fiber carrier with a core-shell structure, the sustained release and intelligent release of bioactive factors can be realized inside the hydrogel, effectively improving the therapeutic effect of the biomaterial and avoiding the problem of reduced efficacy caused by uneven drug release or rapid release of traditional hydrogels.

[0021] (3) By introducing a short fiber reinforcement mechanism, the mechanical strength, toughness and stability of the hydrogel are effectively improved, solving the problems of easy collapse and low strength of traditional hydrogels, and making it more suitable for soft tissue repair.

[0022] (4) Using mature processes such as coaxial electrospinning, cryosectioning, and photocuring, the preparation process is simple, low-cost and large-scale production can be achieved, which is more efficient than the preparation methods of traditional hydrogel materials and has high industrialization value. Description of the Drawings

[0023] Figure 1 It is a scanning electron microscope image of the fiber material prepared by the coaxial electrospinning process in Example 6 of the present invention.

[0024] Figure 2 It is a bright-field microscope image of the short fibers formed in Example 6 of the present invention.

[0025] Figure 3 It is the output voltage curve of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties prepared in Example 6 of the present invention.

[0026] Figure 4 It is the drug release curve of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties prepared in Example 5 and Example 6 of the present invention.

[0027] Figure 5 It is the CCK-8 curve of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties prepared in Example 6 of the present invention. Detailed implementation mode

[0028] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0029] It should be noted that the terms used herein are only for describing the specific implementation mode and are not intended to limit the exemplary implementation mode according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "include" and / or "comprise" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0030] The present invention will be further described in conjunction with specific examples below, and the following examples are only for explaining the present invention and do not constitute a limitation to the present invention. The test samples and test processes used in the following examples include the following content (if the specific experimental conditions are not specified in the examples, they are usually in accordance with conventional conditions or the conditions recommended by the reagent company; the reagents, consumables, etc. used in the following examples, unless otherwise specified, can be obtained from commercial channels).

[0031] Example 1 This example provides a preparation method of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties: (1) Chitosan was added to a 50% acetic acid solution to prepare a 10 wt% solution, stirred until completely dissolved, and then 1 wt% of curcumin was added to form a core layer solution; poly-L-lactic acid was dissolved in hexafluoroisopropanol to prepare a 10 wt% shell layer solution; The core layer solution and the shell layer solution were respectively connected to a 22 / 17 coaxial needle for electrospinning. The voltage was set to 15 kV, and the injection speeds of the core layer solution and the shell layer solution were 0.5 mL / h and 1 mL / h respectively. The fiber filaments were collected by a roller (rotation speed 500 rpm), and aluminum foil was used as the collection substrate to obtain a fiber material with a core-shell structure.

[0032] (2) The fiber material obtained in step (1) was dissolved with tert-butanol and then broken into short fibers of 25-100 µm by a homogenizer at 2000 rpm.

[0033] (3) Dissolve 10 wt% hyaluronic acid methacrylate and 0.5 wt‰ photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and mix them evenly to form a hydrogel precursor solution. Mix 1 wt% of the short fibers obtained in step (2) with the hydrogel precursor solution evenly, and use ultrasonic waves or mechanical stirring to ensure uniformity to form a pre-gel solution.

[0034] (4) Fill the pre-gel solution into the tissue defect site and irradiate it with ultraviolet light for 5 min to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties.

[0035] Example 2 This example provides a preparation method of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties: (1) Add chitosan to 50% acetic acid solution to prepare a 10 wt% solution, stir until completely dissolved, and then add 1 wt% chondroitin sulfate to form a core layer solution; dissolve polycaprolactone in hexafluoroisopropanol to prepare a 10 wt% shell layer solution; Connect the two solutions to a 22 / 17 coaxial needle for electrospinning respectively, set the voltage to 12 kV, and the injection speeds of the core layer solution and the shell layer solution are 0.4 mL / h and 0.7 mL / h respectively; collect the fiber filaments through a roller with a rotation speed of 6000 rpm, and use aluminum foil as the collection substrate to obtain a fiber material with a core-shell structure.

[0036] (2) Place the fiber material obtained in step (1) in a water-soluble cryoembedding medium polyethylene glycol (PEG), perform cryoembedding treatment at -80°C, and then use a cryostat to cut the embedded sample into short fiber materials with a thickness of 100 µm.

[0037] (3) Dissolve 12 wt% hyaluronic acid methacrylate and 0.5 wt‰ photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and mix them evenly to form a hydrogel precursor solution. Mix 1 wt% of the short fibers obtained in step (2) with the hydrogel precursor solution evenly, and use ultrasonic waves or mechanical stirring to ensure uniformity to form a pre-gel solution.

[0038] (4) Fill the pre-gel solution into the tissue defect site and crosslink it by irradiating with ultraviolet light for 5 min to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties.

[0039] Example 3 This example provides a preparation method of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties: (1) Add hyaluronic acid to a 50% acetic acid solution to prepare a 10 wt% solution, stir until completely dissolved, and then add 1 wt% chondroitin sulfate to form a core layer solution; dissolve polycaprolactone in hexafluoroisopropanol to prepare a 10 wt% shell layer solution; Connect the two solutions to a 22 / 17 coaxial needle for electrospinning respectively, set the voltage to 12 kV, the injection speeds of the core layer solution and the shell layer solution are 0.4 mL / h and 0.7 mL / h respectively, and the fiber filaments are collected by a roller rotating at 6000 rpm, with aluminum foil as the collection substrate to obtain a fibrous material with a core-shell structure.

[0040] (2) Place the fibrous material obtained in step (1) in a water-soluble cryoembedding medium, polyvinyl alcohol (PVA), and perform cryoembedding treatment at -80°C. Subsequently, use a cryostat to cut the embedded sample into short fibrous materials with a thickness of 50 µm.

[0041] (3) Dissolve and mix 12 wt% hyaluronic acid methacrylate and 0.5 wt‰ photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone evenly to form a hydrogel precursor solution. Mix 1 wt% of the short fibers obtained in step (2) with the hydrogel precursor solution evenly, and use ultrasonic waves or mechanical stirring to ensure uniformity to form a pre-gel solution.

[0042] (4) Fill the pre-gel solution into the tissue defect site and irradiate it with ultraviolet light for 5 min for crosslinking to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties.

[0043] Example 4 This example provides a preparation method of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties: (1) Add hyaluronic acid to a 50% acetic acid solution to prepare a 10 wt% solution, stir until completely dissolved, and then add 1 wt% resveratrol to form a core layer solution; dissolve poly(lactic-co-glycolic acid) in hexafluoroisopropanol to prepare a 10 wt% shell layer solution; Connect the core layer solution and the shell layer solution to a 22 / 17 coaxial needle for electrospinning respectively, set the voltage to 14 kV, the injection speeds of the core layer solution and the shell layer solution are 0.6 mL / h and 1.2 mL / h respectively, and the fiber filaments are collected by a roller (rotating speed 800 rpm), with aluminum foil as the collection substrate to obtain a fibrous material with a core-shell structure.

[0044] (2) Dissolve the fibrous material obtained in step (1) with tert-butanol and then use a homogenizer to break it into short fibers of 25 - 100 µm at 3000 rpm.

[0045] (3) Dissolve 10 wt% hyaluronic acid methacrylate and 0.5 wt‰ photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and mix them evenly to form a hydrogel precursor solution. Mix 1 wt% of the short fibers obtained in step (2) with the hydrogel precursor solution evenly, and use ultrasonic waves or mechanical stirring to ensure uniformity to form a pre-gel solution.

[0046] (4) Fill the pre-gel solution into the tissue defect site and irradiate it with ultraviolet light for 5 min to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties.

[0047] Example 5 This example provides a preparation method of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties: (1) Add gelatin to a 50% acetic acid solution to prepare a 10 wt% solution, stir until completely dissolved, and then add 1 wt% curcumin to form a core layer solution; dissolve poly(lactic-co-glycolic acid) in hexafluoroisopropanol to prepare a 10 wt% shell layer solution; Connect the core layer solution and the shell layer solution to a 22 / 17 coaxial needle head respectively for electrospinning. Set the voltage to 14 kV, and the injection speeds of the core layer solution and the shell layer solution are 0.6 mL / h and 1.2 mL / h respectively. The fiber filaments are collected by a roller (rotation speed 800 rpm), and aluminum foil is used as the collection substrate to obtain a fiber material with a core-shell structure.

[0048] (2) Dissolve the fiber material obtained in step (1) with tert-butanol, and then use a homogenizer to break it into short fibers of 25 - 100 µm at 3000 rpm.

[0049] (3) Dissolve 10 wt% hyaluronic acid methacrylate and 0.5 wt‰ photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and mix them evenly to form a hydrogel precursor solution. Mix 1 wt% of the short fibers obtained in step (2) with the hydrogel precursor solution evenly, and use ultrasonic waves or mechanical stirring to ensure uniformity to form a pre-gel solution.

[0050] (4) Fill the pre-gel solution into the tissue defect site and irradiate it with ultraviolet light for 5 min to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties.

[0051] Example 6 This example provides a preparation method of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties: (1) Gelatin was added to 50% acetic acid solution to prepare a 10 wt% solution, stirred until completely dissolved, and then 1 wt% chondroitin sulfate was added to form a core layer solution; poly(β-hydroxybutyrate-co-valerate) was dissolved in hexafluoroisopropanol to prepare a 10 wt% shell layer solution; The core layer solution and the shell layer solution were respectively connected to a 22 / 17 coaxial needle for electrospinning. The voltage was set at 15 kV, and the injection rates of the core layer solution and the shell layer solution were 0.1 mL / h and 1 mL / h respectively. The fiber filaments were collected by a roller (rotation speed 1000 rpm), and aluminum foil was used as the collection substrate to obtain a fiber material with a core-shell structure.

[0052] (2) The fiber material obtained in step (1) was dissolved in tert-butanol and then broken into short fibers with a size of 25 - 100 µm by a homogenizer at 8000 rpm.

[0053] (3) 10 wt% methacrylated gelatin and 0.5 wt‰ photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone were dissolved and mixed evenly to form a hydrogel precursor solution. 1 wt% of the short fibers obtained in step (2) were mixed evenly with the hydrogel precursor solution, and ultrasonic waves or mechanical stirring were used to ensure uniformity to form a pre-gel solution.

[0054] (4) The pre-gel solution was filled into the tissue defect site and irradiated with ultraviolet light for 5 min to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties.

[0055] Effect Example 1 In this effect example, a scanning electron microscope and a bright-field microscope were used to observe the morphology of the fiber material prepared in step (1) of Example 6.

[0056] The specific test method is as follows: First, a scanning electron microscope was used to observe the morphology of the fiber material prepared by the electrospinning method. The test results showed that, as Figure 1 shown: The fibers presented an obvious fibrous structure, specifically manifested as uniform slender fibers, and there were no significant fractures or aggregations. Subsequently, the same batch of samples was observed by a bright-field microscope, and the broken fibers showed the morphology of short fibers. As Figure 2 shown: After ultrasonic fragmentation or mechanical shearing treatment, the length of the fibers was significantly reduced, forming a short fiber-like structure. The results showed that the fiber material prepared by the electrospinning method could successfully form a material with a short fiber structure after subsequent treatment.

[0057] Effect Example 2 This effect example used a Rigol DS1102E oscilloscope to test the voltage output characteristics of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties prepared in Example 6 under periodic mechanical pressure to evaluate its electro-responsive performance.

[0058] The specific test method is as follows: The sample of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties was cut into a square with a diameter of 10 mm and clamped between a pair of copper electrodes. The assembled hydrogel device was placed in an environment where a periodic mechanical force of 6 N and 10 Hz was applied. The output voltage was measured in real time through a Rigol DS1102E oscilloscope. The test results are as Figure 3 shown. The injectable short fiber-based hydrogel tissue repair material with electro-responsive properties can effectively convert the applied mechanical energy into electrical signals, fully demonstrating its excellent electro-responsive performance.

[0059] Effect Example 3 This effect example tested the drug sustained-release performance of the injectable short fiber-based hydrogel tissue repair materials with electro-responsive properties prepared in Examples 5 and 6.

[0060] The specific test method is as follows: Samples of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties containing chondroitin sulfate were respectively placed in a release medium containing PBS (pH 7.4) and cultured with shaking at 37°C. Samples were taken at set time points (0, 2, 6, 12, 24 hours), the concentration of CS in the supernatant was measured, and quantitative analysis was carried out through a UV spectrophotometer. An equal volume of fresh PBS was supplemented after each sampling to maintain a constant volume. The final release amount was expressed as normalized to the initial mass of the sample. As Figure 4 shown, the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties prepared in Example 6 continuously released chondroitin sulfate within 24 hours, and the cumulative release amount was significantly higher than that of Example 5, and there was no burst release. The overall release process showed a trend of gradual release, indicating that the material has good controllable drug release performance. By regulating the structure and composition of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties, the release rate and release amount of the drug can be effectively adjusted to meet the requirements of the drug delivery rhythm in different tissue repair processes.

[0061] Effect Example 4 This effect example evaluated the biocompatibility of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties prepared in Example 6 through a CCK-8 cell proliferation experiment.

[0062] The specific test method is as follows: The injectable short fiber-based hydrogel tissue repair material with electro-responsive properties prepared in Example 6 is treated by the extraction solution method. Under the conditions of an extraction ratio of 1:10 and incubation in DMEM culture medium at 37 °C for 24 h, a hydrogel extract is obtained, and this hydrogel extract is used for the culture of L929 fibroblasts. The cells are inoculated into a 96-well plate ( 4 cells per well), and the hydrogel extract (Example 6) and the hydrogel-free extract (control group) are added for culture respectively. The CCK-8 reagent is used for detection on the 3rd, 5th, and 7th days of culture respectively. After incubation for 2 h, the absorbance value (OD) is measured at a wavelength of 450 nm. As Figure 5 shown, the cell proliferation activity of the group in Example 6 at different time points is higher than that of the control group. Especially on the 7th day, a significantly increased OD value is shown, indicating that this material can effectively promote cell proliferation and has good cell compatibility and biosafety.

[0063] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly illustrating the technical solutions of the present invention, rather than limitations on the specific implementation manners of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the claims of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. A preparation method of an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties, characterized in that, Including the steps: (1) Mix the bioactive factor and the natural polymer material solution evenly to form a core layer solution, dissolve the biodegradable material to form a shell layer solution, and further adopt a coaxial electrospinning process to prepare a fiber material with a core-shell structure by using the core layer solution and the shell layer solution; (2) Subject the fiber material obtained in step (1) to cryosectioning, ultrasonic fragmentation or mechanical shearing treatment to obtain short fibers; (3) Dissolve and mix the hydrogel matrix and the photoinitiator evenly to form a hydrogel precursor solution; mix the short fibers in step (2) evenly with the hydrogel precursor solution to form a pre-gel solution; (4) Fill the pre-gel solution obtained in step (3) into the tissue defect site and adopt a photocuring process to form an injectable short fiber-based hydrogel tissue repair material with electro-responsive properties; In step (1), the natural polymer material is a combination of one or more of chitosan, gelatin or hyaluronic acid; The biodegradable material is a combination of one or more of poly(β-hydroxybutyrate-co-valerate), poly-L-lactic acid, polycaprolactone or poly(lactic-co-glycolic acid).

2. The preparation method according to claim 1, characterized in that, In step (1), the bioactive factor is a combination of one or more of curcumin, chondroitin sulfate or resveratrol.

3. The preparation method according to claim 1, characterized in that, In step (1), the process parameters of the coaxial electrospinning process are: the drum collection rotation speed is 100 - 1500 rpm, the voltage is 10 - 20 kV, the injection speed is 0.1 - 2.0 mL / h, and the annealing treatment temperature is from room temperature to -80°C.

4. The preparation method according to claim 1, characterized in that, In step (2), when preparing short fibers by cryosectioning, the fiber material needs to be wrapped by cryoembedding before sectioning, the temperature of the cryoembedding is -80°C, and the embedding reagent is one or more of polyethylene glycol and polyvinyl alcohol.

5. The preparation method according to claim 1, characterized in that, In step (2), the size of the short fibers is 25 - 100 µm.

6. The preparation method according to claim 1, characterized in that, In step (3), the hydrogel matrix is a combination of one or more of methacrylated gelatin, methacrylated hyaluronic acid or methacrylated silk fibroin.

7. The preparation method according to claim 1, wherein In step (3), the photoinitiator is one or more of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, lithium acylphosphonite, 2,4,6-trimethylbenzoyl diphenylphosphine oxide or 2-hydroxy-2-methyl-1-phenyl-1-propanone; the addition amount of the photoinitiator is 0.5 wt‰ - 1 wt‰.

8. The preparation method according to claim 1, characterized in that, In step (4), the photocuring process is: irradiate the site filled with the pre-gel solution with ultraviolet light, and the irradiation time is 5 - 30 min.

9. An injectable short fiber-based hydrogel tissue repair material with electro-responsive properties obtained by the preparation method according to any one of claims 1 to 8.

10. Application of the injectable short fiber-based hydrogel tissue repair material with electro-responsive properties according to claim 8 in tissue repair materials for repairing diabetic infected wounds, articular cartilage repair, oral barrier membrane repair or abdominal wall defect repair.

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