A method for preparing a gradient photocrosslinking hydrogel, a hydrogel prepared by the method and a nerve conduit

Abstract

The application provides a preparation method of gradient photocrosslinking hydrogel, and the hydrogel and nerve conduit prepared by the method. The method comprises the following steps: step one, adding a photocurable hydrogel precursor into a photoinitiator to prepare a hydrogel precursor solution; optionally, adding a bioactive substance or a drug to prepare a drug-loaded hydrogel precursor solution; step two, loading the hydrogel precursor solution or the drug-loaded hydrogel precursor solution prepared in step one into a transparent tube, and performing photocrosslinking by irradiation of a light source to obtain a gradient photocrosslinking hydrogel; wherein a variable gradient gray light mask with a transparency of 0-100% is arranged between the transparent tube and the light source. The gradient crosslinking hydrogel provided by the application can perform single-order release, and better realizes the slow release of bioactive molecules and drugs, and simultaneously serves as a filler of the nerve conduit, and can continuously guide cell migration for a long time during nerve repair.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biological materials, further relates to a preparation method of gradient photo-crosslinking hydrogel, and the hydrogel prepared by the method, and a nerve conduit prepared from the hydrogel. BACKGROUND

[0002] The hydrogel has the characteristics of extracellular matrix, and can promote cell movement and tissue repair, and can load drugs and bioactive substances. The hydrogel is degradable, and can induce cell migration. The degradation time of the hydrogel and the migration of the induced cells are closely related to the crosslinking degree. At present, researchers mainly use ultraviolet light or blue light to photo-crosslink the photo-curable hydrogel. The crosslinking degree of the hydrogel irradiated by uniform light is uniform, and the hydrogel with uniform crosslinking degree has the same degradation rate, which cannot meet the needs of long-term gradual release of growth factors or drugs in the field of tissue repair. The gradient photo-crosslinking hydrogel can achieve gradient degradation, and can control the slow release of the added bioactive substances or drugs in the hydrogel. Therefore, in order to better control the slow release of the loaded drugs and bioactive substances, the gradient photo-crosslinking hydrogel has gradually become the research focus.

[0003] CN103721293A discloses a photo-crosslinking multi-layer gradient hydrogel with controllable release of active factors and a preparation method. The gel structure is three layers, and the main components of each layer are modified gelatin and carboxymethyl chitosan. Three kinds of modified gelatin and modified carboxymethyl chitosan, a crosslinking agent and a photoinitiator are respectively configured into three kinds of reaction liquid, and the three kinds of reaction liquid are sequentially injected into a mold to obtain a multi-layer gradient hydrogel after photo-crosslinking. The multi-layer gradient hydrogel can meet the requirements of gradient structure, composition and controllable release of active factors of materials for tissue repair, but the preparation method is relatively complex, which is not conducive to application. SUMMARY

[0004] To solve the above problems, the present application provides a preparation method of gradient photo-crosslinking hydrogel. The hydrogel with gradient crosslinking degree prepared by the method can be released in a single order, and can better achieve the slow release of bioactive molecules and drugs. At the same time, as a filler of nerve conduit, the hydrogel can guide cell migration for a long time during nerve repair.

[0005] Firstly, one of the purposes of the present application is to provide a preparation method of gradient photo-crosslinking hydrogel, which comprises the following steps:

[0006] Step one, first, the photo-curable hydrogel precursor is added to the photoinitiator to prepare a hydrogel precursor solution; optionally, a bioactive substance or a drug is added to prepare a drug-loaded hydrogel precursor solution;

[0007] Step two, the hydrogel precursor solution or drug-loaded hydrogel precursor solution prepared in step one is loaded into a transparent tube, and light crosslinking is carried out by irradiation of a light source to obtain a gradient light crosslinking hydrogel;

[0008] In the present application, a variable gradient gray mask with a transparency of 0-100% is arranged between the transparent tube and the light source, and the hydrogel obtained by light crosslinking has a continuous gradient crosslinking structure, and the crosslinking degree of the hydrogel gradually increases from small to large transparency, and the hydrogel starts to degrade from the part with small crosslinking degree, and the biologically active substances or drugs filled in the hydrogel can be released along the direction of gradually increasing crosslinking degree, realizing single-order release, and inducing cell migration from the proximal end to the distal end.

[0009] Preferably, the light source is an ultraviolet or blue light source.

[0010] Preferably, in step one, the preparation conditions of the hydrogel precursor solution are as follows: the temperature is 50-60°C, and the heating time is 10-30 min.

[0011] Preferably, in step one, the concentration of the light-curable hydrogel in the hydrogel precursor solution is 5-35 wt%; more preferably, 10-20 wt%.

[0012] Preferably, in step one, the light-curable hydrogel precursor is selected from one or a combination of methyl acrylate gelatin solid, methyl acrylate chitosan, methyl acrylate silk fibroin, and methyl acrylate hyaluronic acid.

[0013] Preferably, in step one, the photoinitiator is selected from one or a combination of lithium salt of phenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone, 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexyl phenyl ketone, and 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide.

[0014] Preferably, in step one, the biologically active substance or drug is selected from one or a combination of nerve growth factor, neurotrophic factor, and deferoxamine.

[0015] Preferably, in step one, the concentration of the biologically active substance or drug in the drug-loaded hydrogel precursor solution is 0-200 μg / mL; more preferably, 50-150 μg / mL.

[0016] Secondly, the present application provides a gradient light crosslinking hydrogel prepared by the preparation method of the first object of the present application.

[0017] Thirdly, the present application provides a nerve conduit comprising the gradient light crosslinking hydrogel of the second object of the present application.

[0018] Specifically, the gradient photocrosslinking hydrogel is used to fill in the nerve conduit, and can guide cell migration for a long time during nerve repair.

[0019] Further, in the present application, the nerve conduit is prepared by the following method:

[0020] Step A, the high molecular polymer solution is added to the syringe and installed on the electrospinning machine propeller, electrospinning is carried out, the high molecular polymer fiber is obtained, and the electrospinning fiber membrane is obtained after the solvent volatilization; preferably, the thickness of the electrospinning fiber membrane is 250-400 μm.

[0021] Step B, the electrospinning fiber membrane prepared in step A is cut into the same length as the gradient photocrosslinking hydrogel, and then the electrospinning fiber membrane is wrapped around the gradient photocrosslinking hydrogel, the gap is bonded with high molecular polymer solution, and the nerve conduit filled with gradient photocrosslinking hydrogel is obtained after drying.

[0022] Preferably, in step A, the electrospinning conditions are:

[0023] The distance between the needle and the receiving device is 10-25 cm;

[0024] The rate of the propeller is 0.5-1.5 mL / h;

[0025] The ambient temperature is 20-30℃;

[0026] The voltage between the two poles of the electrospinning device is 15-25 kV;

[0027] The spinning time is 10-12 h.

[0028] Preferably, in step A, the high molecular polymer is one or a combination of polycaprolactone, polylactic acid-glycolic acid, type I collagen, and methacrylated gelatin.

[0029] Preferably, in step A, the mass concentration of the high molecular polymer solution is 6-15 wt%; more preferably, 10-15 wt%

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] 1. The preparation method and device of the hydrogel provided by the present application are simple, and the process is simple. A gradient gray scale sheet with variable range is used as a light mask, a gradient light transmittance is realized, a hydrogel with gradient crosslinking degree is obtained, and the hydrogel can be degraded gradiently, thereby solving the problem of short-term burst release of growth factors.

[0032] 2、The application provides a simple and convenient method for filling a nerve conduit with a hydrogel, and the light transmission range and illumination time of a light transmission piece can be controlled according to specific application requirements. The gel concentration of the gradient crosslinking drug-loaded hydrogel is controllable, the drug release duration is controllable, the gradient crosslinking drug-loaded hydrogel has good biocompatibility, can meet the needs of nerve repair, and realizes one-way ordered drug release and long-time drug release. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 A device for preparing the gradient crosslinking hydrogel of the application is shown in the schematic diagram, and a gradient photomask plate is placed on a light generator to play a gradient barrier role on the transmitted light. Among them, 1, light generator; 2, gradient photomask plate; 3, gradient light intensity transmitted after shielding by the photomask plate; 4, gradient crosslinking hydrogel;

[0034] Figure 2 The light mask plate with different gradient ranges of transparency prepared in Example 1 of the application;

[0035] Figure 3 The light mask plate with different gradient ranges of transparency prepared in Example 2 of the application;

[0036] Figure 4 The light mask plate with different gradient ranges of transparency prepared in Example 3 of the application;

[0037] Figure 5 The SEM image of the gradient crosslinking hydrogel prepared in Example 3 of the application;

[0038] Figure 6 The growth factor release curve of the nerve conduit prepared in Example 1 of the application. DETAILED DESCRIPTION

[0039] The following will be specifically described in combination with specific drawings and examples. It is necessary to point out here that the following examples are only used to further illustrate the application, and cannot be understood as limiting the protection scope of the application. Some non-essential improvements and adjustments of the application made by those skilled in the art according to the content of the application still belong to the protection scope of the application.

[0040] Example 1

[0041] The following is used to illustrate the preparation of the gradient light crosslinking drug-loaded hydrogel.

[0042] Step one, preparation of solution

[0043] Take the appropriate amount of methacrylated gelatin GelMA (EFL; EFL-GM-60), dissolve in 2.5wt% photoinitiator phenyl (2,4,6-trimethylbenzoyl) lithium phosphate salt LAP at a temperature of 50℃ for 20min, configure a GelMA precursor solution with a mass fraction of 10wt%; dissolve nerve growth factor NGF in the precursor solution to obtain a hydrogel precursor solution loaded with 100μg / mL nerve growth factor NGF.

[0044] Step two,

[0045] Construction of hydrogel mold: take a transparent tube with an inner diameter of 1.5mm, cut the tube into a small tube with a length of 1.5cm as a hydrogel forming mold.

[0046] Construction of light transmission sheet: draw a rectangle with a length of 5cm and a width of 1cm using word, and fill the inside with 20-100%; after printing on the film paper, cut out the rectangle along the lines to use as a photomask (as shown in Figure 2 .

[0047] Slowly inject the drug-loaded hydrogel precursor solution prepared in step one into the transparent tube, try to avoid air bubbles in the tube, and inject the drug-loaded hydrogel precursor solution about 1cm; place the transparent tube containing the drug-loaded hydrogel precursor solution parallel to the gradient extension direction of the photomask (as shown in Figure 1 ), turn on the 405nm blue light generator for 8 seconds to obtain a gradient light cross-linked drug-loaded hydrogel.

[0048] The following is used to illustrate the preparation of a nerve conduit filled with a gradient light cross-linked drug-loaded hydrogel.

[0049] Step A, preparation of electrospun fiber membrane

[0050] Dissolve polycaprolactone (Sigma-Aldrich; 24980-41-4) in a mixed solvent of dichloromethane and N,N-dimethylformamide (mass ratio 8:2) and stir at room temperature to prepare a polycaprolactone solution with a mass fraction of 12wt%; add the polycaprolactone solution to a syringe and install it on the pusher of the electrospinning machine, set the distance between the needle and the receiving device to 15cm, set the pusher rate to 1mL / h, control the environmental temperature at 30℃, set the voltage between the two poles of the electrospinning device to 20kV, and after spinning for 12h, the polycaprolactone fibers are collected, and the residual solvent is volatilized in a fume hood to obtain an inner layer ordered electrospun fiber membrane, with a fiber membrane thickness of 300μm.

[0051] Step B, preparation of a nerve conduit filled with a gradient light cross-linked drug-loaded hydrogel

[0052] The fiber membrane prepared in step A is cut to the same length as the gradient photocrosslinking drug-loaded hydrogel prepared in step two. The cut fiber membrane is tightly wrapped around the gradient photocrosslinking drug-loaded hydrogel, and the gap is bonded with the 12wt% polycaprolactone solution of step A. After drying in the fume hood, the gradient photocrosslinking drug-loaded hydrogel filled nerve conduit is obtained.

[0053] Figure 6 The growth factor release curve of the nerve conduit prepared in this example is shown in the figure. GN is the fiber membrane wrapped gradient crosslinking GelMA hydrogel loaded with NGF; GNP is the proximal end of the fiber membrane wrapped gradient crosslinking GelMA hydrogel loaded with NGF; GNM is the middle end of the fiber membrane wrapped gradient crosslinking GelMA hydrogel loaded with NGF; GND is the distal end of the fiber membrane wrapped gradient crosslinking GelMA hydrogel loaded with NGF. It can be seen from the figure that the proximal end releases from 1 to 5 days at the beginning, while the middle end and the distal end do not release a large amount of NGF at the same time; the middle end releases from 2 to 9 days, and the distal end releases from 4 to 11 days. It can be seen that the gradient hydrogel loaded with NGF can realize the single-order and orderly release function with the change of the crosslinking strength of the hydrogel. Figure 6

[0054] Example 2

[0055] The following is used to illustrate the preparation of gradient photocrosslinking drug-loaded hydrogel.

[0056] Step one, preparation of solution

[0057] Take an appropriate amount of methacrylated hyaluronic acid HAMA (EFL; EFL-HAMA-400K)), dissolve it in 2.5wt% photoinitiator phenyl (2,4,6-trimethylbenzoyl) lithium phosphate salt LAP at a temperature of 60℃ for 20min, and configure it as a HAMA precursor solution with a mass fraction of 15wt%.

[0058] Step two,

[0059] Construction of hydrogel mold: take a transparent tube with an inner diameter of 1.2mm, cut the tube into small tubes with a length of 1.2cm as the hydrogel forming mold.

[0060] Construction of light transmission sheet: draw a rectangle with a length of 5cm and a width of 1cm with word, and the internal filling is selected to be 10-80%; print with film paper, cut out the rectangle after printing with film paper, and cut out the rectangle along the line as the light mask plate (as shown in Figure 3 ).

[0061] ​The hydrogel precursor solution prepared in step one is slowly injected into the transparent tube, and the process should avoid air bubbles in the tube as much as possible. The hydrogel precursor solution is injected about 1 cm; the transparent tube containing the hydrogel precursor solution is placed parallel to the gradient extension direction of the photomask template (as shown in Figure 1 The 405 nm blue light generator is turned on to irradiate for 15 seconds, and a gradient photocrosslinked hydrogel is obtained.

[0062] The following is used to illustrate the preparation of a nerve conduit filled with a gradient photocrosslinked hydrogel.

[0063] Step A, preparation of electrospun fiber membrane

[0064] The polylactic acid-glycolic acid copolymer (Jinan Daigang Biotechnology Co., Ltd.; DG-50DLG150) is dissolved in trifluoroethanol and stirred at room temperature for 24 hours to prepare a 10wt% polylactic acid-glycolic acid copolymer solution; the polylactic acid-glycolic acid copolymer solution is added to a syringe and fixed on the pusher of the electrospinning machine, the distance between the needle and the receiving device is set to 15 cm, the pusher rate is set to 1 mL / h, the environmental temperature is controlled at 25°C, the voltage between the two poles of the electrospinning device is set to 17 kV, and after spinning for 12 h, the polylactic acid-glycolic acid fibers are collected, and the residual solvent is volatilized in a fume hood to obtain an inner ordered electrospun fiber membrane, and the fiber membrane thickness is 300 μm.

[0065] Step B, preparation of a nerve conduit filled with a gradient photocrosslinked hydrogel

[0066] The fiber membrane prepared in step A is cut to the same length as the gradient photocrosslinked hydrogel prepared in step two, and then the cut fiber membrane is tightly wrapped around the gradient photocrosslinked hydrogel, and the gap is bonded with the 10wt% polylactic acid-glycolic acid solution of step A, and then dried in a fume hood to obtain a nerve conduit filled with a gradient photocrosslinked drug-loaded hydrogel.

[0067] Example 3

[0068] The following is used to illustrate the preparation of a gradient photocrosslinked drug-loaded hydrogel.

[0069] Step one, solution preparation

[0070] Methacrylated silk fibroin SilMA (EFL; EFL-SilMA-001)) is dissolved in 2.5wt% photoinitiator lithium phenyl (2,4,6-trimethylbenzoyl) phosphate salt LAP at a temperature of 55°C for 25 min to prepare a 20wt% SilMA precursor solution; nerve growth factor NGF is dissolved in the precursor solution to obtain a hydrogel precursor solution loaded with 150 μg / mL nerve growth factor NGF.

[0071] Step two,

[0072] Construction of hydrogel mold: Take a transparent tube with an inner diameter of 1.5 mm, cut the tube into a small tube with a length of 1.5 cm as a hydrogel forming mold;

[0073] Construction of light transmission sheet: draw a rectangle with a length of 5 cm and a width of 1 cm in word, and fill the inside with a selection of 20-80%; after printing on the film paper, cut out the rectangle along the line as a light mask plate (as shown in Figure 4

[0074] Slowly inject the hydrogel precursor solution prepared in step one into the transparent tube, try to avoid air bubbles in the tube during the process, and inject about 1 cm of the hydrogel precursor solution; place the transparent tube containing the hydrogel precursor solution parallel to the gradient extension direction of the light mask plate (as shown in Figure 1

[0075] Figure 5 SEM images of the hydrogel prepared for this example after lyophilization. As can be seen from the figure, when the light crosslinking is performed, the pore size in the corresponding hydrogel gradually increases from left to right as the transparency of the corresponding light mask plate decreases from left to right. As can be seen from the pore size, the larger the transparency of the light mask plate, the smaller the pore size, and the greater the degree of crosslinking.

[0076] The following is used to illustrate the preparation of a nerve conduit filled with a gradient light crosslinking drug-loaded hydrogel.

[0077] Step A, preparation of electrospun fiber membrane

[0078] Type I collagen (Solarbio; C8060) and methacrylated gelatin GelMA (EFL; EFL-GM-60) were dissolved in trifluoroethanol at a mass ratio of 5:5, stirred at room temperature, and a mixed solution of type I collagen and GelMA with a mass fraction of 10wt% was prepared; the mixed solution of type I collagen and GelMA was added to a syringe and fixed on the pusher of the electrospinning machine, the distance between the needle and the receiving device was set to 15 cm, the pusher rate was set to 1 mL / h, the environmental temperature was controlled at 25℃, the voltage between the two poles of the electrospinning device was set to 17kV, and after 10h of spinning, the type I collagen and GelMA fibers were collected, the residual solvent was allowed to volatilize in a fume hood, and an inner layer ordered electrospun fiber membrane was obtained, the thickness of the fiber membrane was 200μm.

[0079] Step B, preparation of a nerve conduit filled with a gradient light crosslinking drug-loaded hydrogel

[0080] ​​The fiber membrane prepared in step A is cut to the same length as the gradient photocrosslinking drug-loaded hydrogel prepared in step two, and then the cut fiber membrane is tightly wrapped around the gradient photocrosslinking drug-loaded hydrogel. The gap is bonded with a mixed solution of 10wt% type I collagen and GelMA prepared in step A, and then dried in a fume hood to obtain a gradient photocrosslinking drug-loaded hydrogel filled nerve conduit.

[0081] Example 4

[0082] The preparation method of the gradient photocrosslinking drug-loaded hydrogel of this example is the same as that of example 3, except that:

[0083] Step one, preparation of solution

[0084] A GelMA precursor solution with a mass fraction of 12wt% is configured. The photo initiator is 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone. A hydrogel precursor solution loaded with 100μg / mL VEGF and 100μg / mL NGF is configured.

[0085] Step two,

[0086] Construction of light transmission sheet: the internal filling is selected as a light mask plate with a light transmittance of 10-90%.

[0087] Irradiation for 15 seconds by a 405nm ultraviolet light generator to obtain a gradient photocrosslinking drug-loaded hydrogel.

[0088] The preparation method of the nerve conduit of this example is the same as that of example 3, except that:

[0089] Step A, preparation of electrospun fiber membrane

[0090] A solution with a mass ratio of polycaprolactone to gelatin of 4:1 and a mass fraction of 10wt% is prepared to prepare an inner layer of ordered electrospun fiber membrane. The thickness of the fiber membrane is 300μm.

[0091] Example 5

[0092] The preparation method of the gradient photocrosslinking drug-loaded hydrogel of this example is the same as that of example 3, except that:

[0093] Step one, preparation of solution

[0094] A GelMA precursor solution with a mass fraction of 10wt% is configured. The photo initiator is lithium phenyl(2,4,6-trimethylbenzoyl)phosphinate LAP. A hydrogel precursor solution loaded with 100μg / mL NGF and 2mg / ml deferoxamine DFO is configured.

[0095] Step two,

[0096] The construction of the light-transmitting sheet: the internal filling is selected as 20-70% of the photo mask plate.

[0097] The gradient photo-crosslinking drug-loaded hydrogel is obtained by irradiation of the 405 nm ultraviolet light generator for 20 seconds.

Claims

1. A method for preparing a nerve conduit, characterized in that: The preparation method comprises the following steps: Step A: adding a high molecular polymer solution into a syringe and installing it on the propeller of an electrospinning machine to perform electrospinning to obtain high molecular polymer fibers. After the solvent evaporates, an electrospun fiber membrane is obtained; Step B: cutting the electrospun fiber membrane prepared in step A into the same length as the gradient photo-crosslinked hydrogel, then wrapping the electrospun fiber membrane in the gradient photo-crosslinked hydrogel, bonding the gaps with a polymer solution, and drying to obtain a gradient photo-crosslinked hydrogel-filled nerve conduit; The preparation method of the gradient photocrosslinked hydrogel comprises the following steps: Step 1: first, adding a photocurable hydrogel precursor to a photoinitiator to prepare a hydrogel precursor solution; then adding a bioactive substance or drug to prepare a drug-loaded hydrogel precursor solution; Step 2: The drug-loaded hydrogel precursor solution prepared in step 1 is placed in a transparent tube and photocrosslinked by irradiation with a light source to obtain a gradient photocrosslinked hydrogel; Wherein, in the step 2, a variable gradient grayscale light mask with a transparency of 0-100% is provided between the transparent tube and the light source.

2. The method for preparing a nerve conduit according to claim 1, characterized in that: In the step 1, The photocurable hydrogel precursor is selected from one or a combination of methacrylated gelatin solid, methacrylated chitosan, methacrylated silk fibroin, and methacrylated hyaluronic acid; and / or, The photoinitiator is selected from one or a combination of phenyl (2,4,6-trimethylbenzoyl) lithium phosphate, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone, 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexyl phenyl ketone, and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide.

3. The method for preparing a nerve conduit according to claim 1, characterized in that: In the step 1, The preparation conditions of the hydrogel precursor solution are: temperature of 50-60° C., heating for 10-30 min; and / or, The concentration of the photocurable hydrogel in the hydrogel precursor solution is 5 to 35 wt %.

4. The method for preparing a nerve conduit according to claim 3, characterized in that: In the step 1, the concentration of the photocurable hydrogel in the hydrogel precursor solution is 10-20 wt %.

5. The method for preparing a nerve conduit according to claim 1, characterized in that: In the step 1, The bioactive substance or drug is selected from one or a combination of nerve growth factor, neurotrophic factor, and deferoxamine; and / or, The concentration of the bioactive substance or drug in the drug-loaded hydrogel precursor solution is 0-200 μg / mL.

6. The method for preparing a nerve conduit according to claim 5, characterized in that: In the step 1, the concentration of the bioactive substance or drug in the drug-loaded hydrogel precursor solution is 50-150 μg / mL.

7. The method for preparing a nerve conduit according to claim 1, characterized in that: In the step 2, the light source is ultraviolet light or blue light.

8. The method for preparing a nerve conduit according to claim 1, characterized in that: In step A, the electrospinning conditions are: The distance between the needle and the receiving device is 10~25cm; The propeller rate is 0.5–1.5 mL / h; The ambient temperature is 20~30℃; The voltage between the two electrodes of the electrospinning device is 15~25 kV; The spinning time is 10~12 h.

9. The method for preparing a nerve conduit according to claim 1, characterized in that: The high molecular polymer is one or a combination of polycaprolactone, polylactic acid-glycolic acid, type I collagen, and methacrylated gelatin; and / or, The mass concentration of the high molecular polymer solution is 6-15wt%.

10. The method for preparing a nerve conduit according to claim 9, characterized in that: The mass concentration of the high molecular polymer solution is 10-15 wt %.

11. A nerve conduit, characterized in that: Prepared by the method according to any one of claims 1 to 10.

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