Self-assembly temperature-sensitive hydrogel for nerve repair and preparation method thereof

Abstract

The invention provides a self-assembled temperature-sensitive hydrogel for neural restoration and a preparation method thereof. The hydrogel comprises the following raw materials: poloxamer, an acellular matrix and a neural factor in a mass concentration ratio of (5-10): (10-20): (1-4), preferably 5: 15: 1. The preparation method comprises the following steps: respectively preparing a poloxamer solution and an acellular matrix solution, mixing and heating the poloxamer solution and the acellular matrix solution to form a double-network three-dimensional gel structure, adding the nerve factors, stirring or ultrasonically dispersing, and heating to form the bioactive hydrogel. The hydrogel can rapidly form a stable three-dimensional structure at the body temperature, a support is provided for nerve repair, cell adhesion and proliferation are supported, and the added nerve factors are beneficial to maintaining the activity of neurons. Meanwhile, the hydrogel is in a liquid state at a low temperature, is convenient to inject, is fixed at a body temperature, is adjustable in degradation rate, is non-toxic, is suitable for local nerve injury treatment, and improves the bioavailability and safety of a nerve repair material.

Description

Technical Field

[0001] The present invention belongs to the field of biomedical materials, and in particular relates to a self-assembled thermosensitive hydrogel for nerve repair and a preparation method thereof. Background Art

[0002] Although autologous or allogeneic nerve tissue is used for repair, these materials have good repair effects, but there are problems such as limited donors and immune rejection. Nerve tubes made of biodegradable materials (such as collagen, polylactic acid, etc.) are difficult to precisely control the degradation rate of these materials. Too fast degradation may lead to an inflammatory response, while too slow degradation may affect the remodeling of nerve fibers and affect nerve fiber growth. In addition, despite numerous studies, existing technologies and materials still face the following challenges: 1. Insufficient regulation of the nerve regeneration microenvironment. Nerve injury repair depends on the complex interaction between the extracellular matrix, growth factors and neurons. However, existing materials are still insufficient in providing a suitable microenvironment, especially in promoting neuronal axon extension and reducing scar tissue formation, and further optimization is still needed. 2. Uncertainty in functional recovery. Although nerve conduits and biomaterials can promote nerve fiber growth, many nerve repair schemes only focus on structural repair and ignore functional recovery. How to ensure that new nerve fibers can accurately connect to the target tissue and restore their original physiological functions remains a key issue that needs to be overcome.

[0003] Peripheral nerve injury may be caused by a variety of factors such as mechanical damage, ischemia, inflammation, and toxic effects. Common causes include: car accidents, sports injuries, etc., which lead to nerve rupture or compression: diseases such as diabetes can cause neuropathy, or chemotherapy drugs, heavy metal poisoning, etc., may lead to neurodegeneration. At present, the repair methods of peripheral nerve injury mainly include: 1. Autologous nerve transplantation, but it is difficult to popularize due to insufficient donors and structural matching problems. 2. Use biomaterials (such as collagen, polylactic acid) to make artificial nerve conduits to guide the growth of nerve fibers, but existing conduit materials are difficult to provide a suitable microenvironment, which affects nerve regeneration. 3. Stem cell therapy: Use mesenchymal stem cells or neural stem cells to promote nerve regeneration, and the survival rate and differentiation direction of transplanted cells are difficult to accurately control. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a self-assembling thermosensitive hydrogel for nerve repair and a preparation method thereof. The hydrogel has thermosensitive self-assembly properties, remains liquid at low temperatures, is easy to inject, and quickly forms a stable three-dimensional gel structure under body temperature conditions. It is suitable as a nerve repair scaffold to promote nerve cell adhesion, growth and axon regeneration.

[0005] The present invention is achieved by providing a self-assembled thermosensitive hydrogel for nerve repair, wherein the raw materials include poloxamer, acellular matrix and nerve factors, and the mass concentration ratio of the acellular matrix, poloxamer and nerve factors is 5-10:10-20:1-4.

[0006] Furthermore, the mass concentration ratio of the decellularized matrix, poloxamer, and neural factor is 5:15:1.

[0007] A method for preparing the self-assembled thermosensitive hydrogel for nerve repair comprises the following steps:

[0008] (1) Preparing a poloxamer solution: adding poloxamer to deionized water and dissolving it to form a homogeneous solution;

[0009] (2) Preparation of acellular matrix solution: Dissolve the acellular matrix powder in 0.01 M HCl containing 0.9 mg / ml to 1.1 mg / ml pepsin, and stir at 250 rpm to 350 rpm for 22 h to 26 h to form a homogeneous solution; then adjust the pH to 6.5 to 7.5 with 0.1 M NaOH and store in a refrigerator at 2°C to 5°C until used;

[0010] (3) Forming a self-assembled thermosensitive hydrogel: mixing the poloxamer solution with the acellular matrix solution and heating them to form a double-network three-dimensional gel structure;

[0011] (4) Adding neural factors: Add neural factors to the system after mixing the poloxamer solution and the decellularized matrix solution, uniformly disperse them through mechanical stirring or ultrasonic vibration, and form a bioactive hydrogel under heating conditions at 36°C to 38°C.

[0012] Furthermore, the temperature for dissolving the poloxamer in step (1) is 4°C to 10°C.

[0013] Furthermore, when the decellularized matrix powder is dissolved in step (2), its concentration is 2 mg / ml to 20 mg / ml.

[0014] Furthermore, in step (3), the water bath heating temperature is 30° C. to 37° C., and the heating time is 30 to 40 minutes.

[0015] Furthermore, the decellularized matrix in step (2) is a small intestine decellularized matrix, and its preparation process is as follows:

[0016] (a) Raw material selection: Select healthy pig intestines that are free of pathogens;

[0017] (b) Preliminary treatment: removing the muscle layer and mucosal layer of the porcine small intestine, and treating the treated small intestine sample in a pancreatic enzyme solution at room temperature for 22 to 26 hours, with the solution being replaced every 11 to 13 hours;

[0018] (c) Rinse residue: Rinse the sample 2-5 times with ultrapure water;

[0019] (d) Secondary treatment: the small intestine was immersed in a solution containing 1% polyethylene glycol octylphenyl ether and stirred at 37°C for 24 h;

[0020] (e) Enzyme treatment: Incubate the sample with 50 U / mL of DNase at 36°C–38°C for 12 h. Add 1000 U of DNase to 200 mL of water and add the resulting solution to 10 g of small intestine sample (wet weight). The incubation process is performed in a water bath or incubator.

[0021] (f) Re-washing: Wash the sample with ultrapure water 2–5 times, each washing time being 12–20 minutes, and then filter out excess water;

[0022] (g) Disinfection: Immerse the sample in a 1% peracetic acid solution containing 4% ethanol and stir at room temperature for 3.5 to 4.5 hours. Rinse with PBS 2 to 5 times for 10 to 20 minutes each time and drain.

[0023] (h) Drying and storage: Freeze the sample at -25°C to -15°C for 2 h to 2.5 h, then use a freeze dryer to dry for 40 h to 50 h. Finally, sterilize it with gamma rays or ethylene oxide and store it at 2°C to 5°C.

[0024] Furthermore, the ratio of the pancreatic enzyme solution in process (b) is to add 150 ml of pancreatic enzyme and 3 g of sodium lauryl sulfate to every 10 g of small intestine sample.

[0025] Furthermore, in process (d), the solution containing 1% polyethylene glycol octylphenyl ether is prepared by adding 10 ml of Triton X-100 and 1000 ml of water per 10 g of small intestine sample.

[0026] Furthermore, the ratio of the 1% peracetic acid solution containing 4% ethanol in process (g) is 20 ml of ethanol, 5 ml of peracetic acid and 480 ml of deionized water.

[0027] Compared with the background art, the self-assembled thermosensitive hydrogel for nerve repair described in the present invention adopts the small intestine decellularized matrix as its raw material. The decellularized matrix in its double network structure can provide a natural extracellular matrix, which can support cell adhesion and proliferation, create favorable conditions for the growth and extension of neuronal axons, and thus optimize the neural microenvironment. By adding neural factors to the hydrogel, the neuronal survival rate is improved and apoptosis is reduced. During the process of nerve damage repair, the activity of neurons is maintained, a more favorable environment is provided for nerve regeneration, and at the same time, the recovery of nerve function is enhanced, the repair of damaged tissue is accelerated, and the neural regeneration microenvironment is further improved.

[0028] This hydrogel can rapidly form a stable three-dimensional gel structure at body temperature, making it suitable for use as a nerve repair scaffold. This structure not only guides the growth of nerve fibers, but its stability also helps new nerve fibers precisely connect to target tissues. The hydrogel's three-dimensional gel structure provides a suitable environment for cell adhesion and growth, making it suitable for use as a culture matrix for neural stem cells or mesenchymal stem cells. By culturing stem cells in this hydrogel and transplanting them for treatment, it helps to improve the survival rate of transplanted cells and control their differentiation direction, thereby promoting the recovery of neural function and increasing the certainty of functional recovery.

[0029] The hydrogel remains liquid at low temperatures such as 4°C, making it easy to inject into the target area through minimally invasive surgery; it quickly transforms into a gel structure at body temperature such as 37°C, ensuring local fixation and avoiding diffusion loss, so that it can be accurately positioned, suitable for the treatment of local nerve damage, improving the bioavailability of nerve repair materials, and overcoming the inconveniences of insufficient autologous nerve transplant donors, structural matching problems, and the difficulty of accurate placement of artificial nerve conduits; the rheological properties of poloxamer make the degradation rate of the hydrogel adjustable, which can avoid excessive degradation leading to inflammatory reactions, or excessive degradation affecting tissue replacement. In addition, the products after hydrogel degradation are non-toxic and can be metabolized and absorbed by the body, ensuring the safety of long-term application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a flowchart of the preparation process of the decellularized matrix of the present invention;

[0031] Figure 2 This is a flowchart for the preparation of small intestine decellularized matrix;

[0032] Figure 3 FTIR spectra of the decellularized matrix, poloxamer and composite hydrogel of the present invention;

[0033] Figure 4 This is an optical image of the in-situ gelation of the hydrogel of the present invention;

[0034] Figure 5This is a micrograph of the effect of the neural factor of the present invention on cell morphology;

[0035] Figure 6 Cell survival and proliferation curves; DETAILED DESCRIPTION

[0036] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0037] Example 1: A self-assembled thermosensitive hydrogel for nerve repair, the raw materials including pluronic, acellular matrix and nerve factors, the mass concentration ratio of the acellular matrix, pluronic and nerve factors is 5-10:10-20:1-4; the acellular matrix is ​​a small intestine acellular matrix.

[0038] Poloxamer is a non-ionic surfactant composed of polyoxyethylene (PEO) and polyoxypropylene (PPO). It is thermosensitive and can be used for local delivery of growth factors or drugs, forming a stable gel at body temperature, improving the targeting and sustained-release effect of drugs. It can provide a suitable microenvironment to promote cell attachment and growth. In addition, it can be combined with other biomaterials (such as heparin) to enhance its tissue repair ability. When its mass concentration ratio is 15, the gel structure formed can better encapsulate and release neural factors, and interact with the decellularized matrix to form a stable double-network three-dimensional gel structure, which is beneficial to nerve repair.

[0039] The decellularized matrix used is the decellularized small intestine matrix. The decellularized small intestine matrix (SIS-dECM) is mainly derived from the submucosa of the porcine small intestine. After decellularization, cells, DNA and immunogenic substances are removed, and a variety of bioactive components of the natural extracellular matrix (ECM) are retained: collagen (mainly type I and type III), which provides structural support. Glycosaminoglycans (GAGs), such as heparin, chondroitin sulfate, and hyaluronic acid, promote cell adhesion and tissue repair. Cell adhesion molecules (fibronectin, laminin) help cell migration and proliferation. Growth factors (TGF-β, bFGF, VEGF, etc.) promote angiogenesis and tissue regeneration. Current studies have shown that the decellularized small intestine matrix (SIS-dECM) can be used as a neural scaffold to support the growth of nerve fibers and axon extension without causing obvious immune rejection reactions. It can provide a suitable extracellular matrix to promote the adhesion and differentiation of nerve cells. When bridging the sciatic nerve defect in rats, it can promote nerve fiber regeneration. When the mass concentration ratio is 5, it can provide sufficient bioactive ingredients to create a suitable microenvironment for nerve cells without affecting the overall structure and performance of the hydrogel.

[0040] Neurokines are mainly composed of proteins, peptides or small molecule compounds, and have been widely used in nerve injury repair. The important roles played in nerve injury repair include: 1. Promoting axon regeneration: NGF and BDNF can stimulate nerve fiber growth and improve nerve function recovery. 2. Reducing nerve cell apoptosis: GDNF and bFGF can protect damaged neurons and reduce cell death. 3. Enhancing myelin repair: BDNF and NT-3 contribute to myelin formation and improve the efficiency of nerve signal conduction. 4. Improving the neural microenvironment: Neurokines can regulate inflammatory responses and optimize nerve regeneration conditions. When the mass concentration ratio is 1, it can not only ensure that the neurokines play an effective role, but also avoid cytotoxicity or other adverse effects due to excessive concentration, and synergistically promote nerve repair with decellularized matrix and poloxamer.

[0041] Example 2: Figure 1 As shown, the method for preparing a self-assembled thermosensitive hydrogel for nerve repair comprises the following steps:

[0042] (1) Preparing a poloxamer solution: adding poloxamer to deionized water and dissolving it to form a homogeneous solution;

[0043] (2) Preparation of acellular matrix solution: Dissolve the acellular matrix powder in 0.01 M HCl containing 0.9 mg / ml to 1.1 mg / ml pepsin, and stir at 250 rpm to 350 rpm for 22 h to 26 h to form a homogeneous solution; then adjust the pH to 6.5 to 7.5 with 0.1 M NaOH and store in a refrigerator at 2°C to 5°C until used;

[0044] (3) Forming a self-assembled thermosensitive hydrogel: mixing the poloxamer solution with the acellular matrix solution and heating them to form a double-network three-dimensional gel structure;

[0045] (4) Adding neural factors: Add neural factors to the system after mixing the poloxamer solution and the decellularized matrix solution, uniformly disperse them through mechanical stirring or ultrasonic vibration, and form a bioactive hydrogel under heating conditions at 36°C to 38°C.

[0046] The poloxamer is dissolved at a temperature of 4°C to 10°C in step (1); the acellular matrix powder is dissolved at a concentration of 2 mg / ml to 20 mg / ml in step (2); and the water bath is heated at a temperature of 30°C to 37°C for 30 to 40 minutes in step (3).

[0047] Example 3: Figure 2 The decellularized matrix is ​​a small intestine decellularized matrix, and its preparation process is as follows:

[0048] (a) Raw material selection: Select pig small intestines that are free of pathogen contamination and from healthy sources;

[0049] (b) Preliminary treatment: The muscle layer and mucosal layer of the porcine small intestine were removed, and the small intestine sample was immersed in a pancreatic enzyme solution with a ratio of 150 ml of pancreatic enzyme and 3 g of sodium dodecyl sulfate (SDS) per 10 g of sample. The solution was treated at room temperature for 24 h, and the solution was changed every 12 h.

[0050] (c) Rinse residue: rinse the sample three times with ultrapure water;

[0051] (d) Secondary treatment: The small intestine was immersed in a 1% Triton X-100 solution (10 ml Triton X-100 and 1000 ml water per 10 g sample) and stirred at 37°C for 24 h.

[0052] (e) Enzyme treatment: Incubate the sample with 50 U / mL deoxyribonuclease (DNase) at 37°C for 12 h. Add 1000 U of DNase to 200 mL of water. Pour the resulting solution into a 10 g wet weight sample. The incubation can be performed in a water bath or incubator.

[0053] (f) Rewashing: Wash the sample three times with ultrapure water, each washing time for 15 minutes, and then filter out excess water;

[0054] (g) Disinfection: Immerse the sample in a 1% peracetic acid solution containing 4% ethanol (20 ml ethanol, 5 ml peracetic acid, 480 ml deionized water) and stir at room temperature for 4 hours. Rinse with PBS three times for 15 minutes each time and drain.

[0055] (h) Drying and storage: Freeze the sample at -20°C for 2 h, dry it in a freeze dryer for 3 days, sterilize it with gamma radiation or ethylene oxide, and store it at 4°C.

[0056] Example 4: Based on Examples 1 to 3, the small intestinal decellularized matrix solution was prepared as follows: 60 mg of the small intestinal decellularized matrix was weighed and dissolved in 4 ml of a 0.1 M HCl solution containing 1 mg / ml, stirred at 300 rpm for 24 h, and then the pH was adjusted to 7 with 0.1 M NaOH. The solution was allowed to stand at low temperature (30-37°C) for 1 hour to allow it to self-assemble into a SIS-ECM hydrogel. At this time, the hydrogel concentration was 10 mg / mL.

[0057] Preparation of the poloxamer solution: 300 mg of poloxamer 407 was weighed, 1 mL of deionized water was added to dissolve it, and ultrasonic vibration was performed for 5 minutes to fully mix it to obtain a poloxamer solution with a concentration of 300 mg / mL.

[0058] Example 5: This example is based on Example 4. First, the small intestine decellularized matrix solution and the poloxamer solution were mixed uniformly at a volume ratio of 1:1, and then placed in a 37°C water bath and heated for 30 minutes. Under this temperature condition, Figure 2 As shown in the FTIR spectrum, the components in the solution formed physical cross-links through non-covalent hydrogen bonding, thereby obtaining a hydrogel with a stable double-fiber network three-dimensional structure. The final concentration of the hydrogel was 150 mg / mL poloxamer + 7.5 mg / mL small intestine decellularized matrix, which was recorded as S0.

[0059] In addition, to prepare a hydrogel containing neuropeptide, 2 mg of neuropeptide (PP) was added to a mixed solution of small intestinal decellularized matrix and poloxamer, and the mixture was thoroughly mixed to form a bioactive neuropeptide nanofiber network structure hydrogel, which was recorded as S1.

[0060] Example 6: Based on Example 4, this example conducted related experiments. A small intestinal decellularized matrix solution and a poloxamer solution were mixed uniformly at a volume ratio of 2:1 and then heated in a 37°C water bath for 30 minutes. During this process, physical crosslinks were formed via non-covalent hydrogen bonding, resulting in a stable, dual-fiber network hydrogel with a three-dimensional structure. The final concentration was 100 mg / mL poloxamer + 10 mg / mL small intestinal decellularized matrix.

[0061] At the same time, a hydrogel sample containing neuropeptide was prepared: 2 mg of neuropeptide (PP) was added to a mixed solution of small intestinal decellularized matrix and poloxamer, and the mixture was thoroughly mixed to form a bioactive neuropeptide nanofiber network structure hydrogel, which was recorded as S2.

[0062] Example 7: This example builds on Example 4. A small intestinal decellularized matrix solution and a poloxamer solution were mixed uniformly at a volume ratio of 1:2 and then heated in a 37°C water bath for 30 minutes. During this heating process, physical crosslinks formed through non-covalent hydrogen bonding, resulting in a stable, dual-fiber network hydrogel with a three-dimensional structure. The final concentration of the hydrogel was 200 mg / mL poloxamer + 5 mg / mL small intestinal decellularized matrix.

[0063] In addition, a hydrogel containing neuropeptide was prepared: 2 mg of neuropeptide (PP) was added to a mixed solution of small intestinal decellularized matrix and poloxamer, and the mixture was fully mixed to form a bioactive neuropeptide nanofiber network structure hydrogel, which was recorded as S3.

[0064] The S0, S1, S2, and S3 hydrogel samples prepared in Examples 5, 6, and 7, like the PBS control, showed no significant negative impact on cell survival. This suggests that hydrogels formed by mixing the decellularized small intestinal matrix solution with the poloxamer solution in varying volume ratios, as well as hydrogels formed by adding the neurophilin (PP), exhibit good cytocompatibility and do not significantly affect cell survival.

[0065] As can be seen from the chart, the S0 and S1 samples prepared in Example 5 performed relatively ordinary in terms of cell proliferation, and did not show a significant advantage on day 7 compared with the PBS group and other groups. The S2 sample prepared in Example 6 and the S3 sample prepared in Example 7 had higher OD values ​​on day 7. This shows that when the small intestine decellularized matrix solution and the poloxamer solution are mixed in a volume ratio of 2:1 and 1:2 to form a hydrogel structure, and when the neurophilic peptide (PP) is added, it has a better promoting effect on cell proliferation, provides a more suitable microenvironment for cell growth, and is conducive to cell proliferation.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A self-assembled thermosensitive hydrogel for nerve repair, characterized in that: The raw materials include poloxamer, decellularized matrix and nerve factor, and the mass concentration ratio of the decellularized matrix, poloxamer and nerve factor is 5-10:10-20:1-4.

2. The self-assembled thermosensitive hydrogel for nerve repair according to claim 1, characterized in that: The mass concentration ratio of the decellularized matrix, poloxamer and neural factor is 5:15:

1.

3. A method for preparing a self-assembled thermosensitive hydrogel for nerve repair according to any one of claims 1 to 2, characterized in that: The steps include: (1) Preparing a poloxamer solution: adding poloxamer to deionized water and dissolving it to form a homogeneous solution; (2) Preparation of decellularized matrix solution: Dissolve the decellularized matrix powder in a solution containing 0.9 mg / ml to 1.1 mg / ml pepsin. (3) was added to 0.01 M HCl and stirred at 250 rpm to 350 rpm for 22 h to 26 h to form a homogeneous solution; then the pH was adjusted to 6.5 to 7.5 with 0.1 M NaOH and stored in a refrigerator at 2 ° C to 5 ° C until used; (4) Forming a self-assembled thermosensitive hydrogel: mixing the poloxamer solution with the decellularized matrix solution and heating them to form a double-network three-dimensional gel structure; (5) Adding neural factors: Add neural factors to the system after mixing the poloxamer solution and the decellularized matrix solution, uniformly disperse them by mechanical stirring or ultrasonic vibration, and form a bioactive hydrogel under heating conditions at 36°C to 38°C.

4. The method for preparing the hydrogel according to claim 3, wherein: The temperature for dissolving poloxamer in step (1) is 4°C to 10°C.

5. The method for preparing the hydrogel according to claim 3, wherein: When the decellularized matrix powder is dissolved in step (2), its concentration is 2 mg / ml to 20 mg / ml.

6. The method for preparing the hydrogel according to claim 3, wherein: In step (3), the water bath is heated at a temperature of 30° C. to 37° C. for 30 to 40 minutes.

7. The method for preparing the hydrogel according to claim 3, wherein: The decellularized matrix in step (2) is a small intestine decellularized matrix, and its preparation process is as follows: (a) Raw material selection: Select healthy pig intestines that are free of pathogen contamination; (b) Preliminary treatment: removing the muscle layer and mucosal layer of the porcine small intestine, and treating the treated small intestine sample in a pancreatic enzyme solution at room temperature for 22 to 26 hours, with the solution being replaced every 11 to 13 hours; (c) Rinse residue: rinse the sample 2-5 times with ultrapure water; (d) Secondary treatment: the small intestine was immersed in a solution containing 1% polyethylene glycol octylphenyl ether and stirred at 37°C for 24 h; (e) Enzyme treatment: Incubate the sample with 50 U / mL of DNase at 36°C–38°C for 12 h. Add 1000 U of DNase to 200 mL of water and add the resulting solution to 10 g of small intestine sample (wet weight). The incubation process is performed in a water bath or incubator. (f) Re-washing: Wash the sample with ultrapure water 2–5 times, each washing time being 12–20 minutes, and then filter out excess water; (g) Disinfection: Immerse the sample in a 1% peracetic acid solution containing 4% ethanol and stir at room temperature for 3.5 to 4.5 hours. Rinse with PBS 2 to 5 times for 10 to 20 minutes each time and drain. (h) Drying and storage: Freeze the sample at -25°C to -15°C for 2 h to 2.5 h, then use a freeze dryer to dry for 40 h to 50 h. Finally, sterilize it with gamma rays or ethylene oxide and store it at 2°C to 5°C.

8. The self-assembled thermosensitive hydrogel for nerve repair according to claim 7, characterized in that: The ratio of the pancreatic enzyme solution in process (b) is to add 150 ml of pancreatic enzyme and 3 g of sodium lauryl sulfate to every 10 g of small intestine sample.

9. The self-assembled thermosensitive hydrogel for nerve repair according to claim 7, characterized in that: In process (d), the solution containing 1% polyethylene glycol octylphenyl ether is prepared by adding 10 ml of Triton X-100 and 1000 ml of water per 10 g of small intestine sample.

10. The self-assembled thermosensitive hydrogel for nerve repair according to claim 7, characterized in that: The ratio of the 1% peracetic acid solution containing 4% ethanol in process (g) is 20 ml of ethanol, 5 ml of peracetic acid and 480 ml of deionized water.

Images