Conductive shape memory polymer device for nerve repair, preparation method and repair method
阅读说明：本技术 用于神经修复的导电形状记忆聚合物装置、制备方法及修复方法 (Conductive shape memory polymer device for nerve repair, preparation method and repair method ) 是由 吴雪莲 杨建� 屈阳 郭玉琴 叶子豪 于 2021-02-26 设计创作，主要内容包括：本发明提供了一种用于神经修复的导电形状记忆聚合物装置、制备方法及修复方法,所述装置包括形状记忆聚合物填充体,和用于包覆填充体和断裂神经两端的形状记忆聚合物包覆体；所述形状记忆聚合物填充体内部具有供神经修复生长的通道,所述柔性形状记忆包覆体和形状记忆聚合物填充体同时具备形状记忆、导电、生物相容性和生物降解性特性。通过对具有形状记忆效应的装置进行预变形处理,使神经导管与断裂神经两端更紧密包裹,利于电信号在神经束中的传导。形状记忆聚合物和导电聚合物形成的半互穿聚合物网络结构,使导电聚合物嵌入到基体中,实现导电功能的同时,增加导电稳定性。(The invention provides a conductive shape memory polymer device for nerve repair, a preparation method and a repair method, wherein the device comprises a shape memory polymer filler and shape memory polymer coatings for coating the filler and two ends of a broken nerve; the flexible shape memory coating and the shape memory polymer filler have the characteristics of shape memory, electric conduction, biocompatibility and biodegradability at the same time. The device with the shape memory effect is subjected to pre-deformation treatment, so that the nerve conduit and two ends of a broken nerve are more tightly wrapped, and the conduction of an electric signal in a nerve bundle is facilitated. The semi-interpenetrating polymer network structure formed by the shape memory polymer and the conducting polymer enables the conducting polymer to be embedded into a matrix, thereby realizing the conducting function and simultaneously increasing the conducting stability.)
1. A conductive shape memory polymer device for nerve repair, comprising: a shape memory polymer filler (1) and a shape memory polymer coating (3) for coating the filler (1) and two ends of a broken nerve; the shape memory polymer filler (1) is internally provided with a channel for nerve repair growth, and the flexible shape memory coating body (3) and the shape memory polymer filler (1) have the characteristics of shape memory, electric conduction, biocompatibility and biodegradability at the same time.
2. The conductive shape memory polymer device for nerve repair according to claim 1, wherein the channels inside the filling body (1) for nerve repair growth are three-dimensional network-like pores and/or axial channels running through the filling body (1).
3. The conductive shape memory polymer device for nerve repair of claim 1, wherein the flexible shape memory polymer coating (3) and the shape memory polymer filler (1) are semi-interpenetrating polymer network structure of shape memory polymer and conductive polymer with biocompatibility and biodegradable characteristics, and the conductivity of the shape memory polymer device for nerve repair ranges from 10-7S/cm～104S/cm; the shape fixing rate of the shape memory polymer device is 70-99%; after being heated, the shape recovery rate is 20-99%, and the shape recovery temperature is 25-50 ℃.
4. The conductive shape memory polymer device for nerve repair according to claim 2, wherein the shape memory polymer filler (1) having a three-dimensional network-like pore structure is a shape memory polymer foam material.
5. The conductive shape memory polymer device for nerve repair according to claim 3, wherein the flexible shape memory polymer coating (3) and the shape memory polymer filler (1) matrix material are: one or more of chitosan, collagen, polyurethane, polyvinyl alcohol, polylactic acid, polycaprolactone and polyglycolic acid; the conductive polymer is polyaniline.
6. The conductive shape memory polymer device for nerve repair according to claim 2, wherein the shape memory filler (1) of the three-dimensional network-like pore structure has a pore diameter of 4-50 μm.
7. The conductive shape memory polymer device for nerve repair according to claim 2, wherein the axial channels through the filling body (1) have a diameter of 50 μm to 150 μm in uniform distribution.
8. The method of making a conductive shape memory polymer device for nerve repair of claim 2, comprising the steps of:
(1) preparing a cylindrical shape memory polymer foam material as a shape memory polymer filler (1); preparing a film-shaped shape memory polymer coating (3);
(2) the channels penetrating along the radial direction are uniformly distributed on the cross section of the cylindrical shape memory polymer filling body (1);
(3) putting the shape memory filler (1) and the shape memory polymer coating body (3) processed in the step (2) into an aniline solvent, and fully swelling the shape memory filler (1) and the shape memory polymer coating body; meanwhile, the cells in the shape memory polymer filler (1) expand to open during the swelling process, thereby forming through micropore channels;
(4) introducing an oxidant solution into the swelled through filler (1) and the shape memory polymer coating (3), wherein conductive polyaniline generated by polymerizing the oxidant and aniline is respectively distributed at a certain depth on the surface layer of the coating (3) and at a certain depth on the surfaces of pore channels and micropore channels of the filler (1), and the matrix of the filler (1) and the coating (3) respectively form an interpenetrating polymer network structure with the polyaniline;
(5) drying treatment is carried out to obtain the conductive shape memory polymer coating body (3) and the conductive shape memory polymer filling body (1).
9. The method of nerve repair of a conductive shape memory polymer device for nerve repair of claim 1, comprising the steps of:
(1) preparing a shape memory polymer filling body (1), matching the length of the filling body with the distance between two ends of a broken nerve, matching the diameter of the filling body with the inner diameter of a broken nerve mantle, fixing the filling body at a nerve breakage position, and contacting a nerve breakage surface;
(2) the initial shape of the film of the flexible shape memory polymer coating body (3) is a curl shape, and the film is a plane after pre-deformation treatment; placing the nerve fracture site at the nerve fracture site, applying stimulation to enable the nerve fracture site to be curled and restored, and tightly coating the filling body (1) and two ends of the nerve fracture site;
(3) applying electrical stimulation to two ends of the coating body (3) and the filling body (1) so as to accelerate the growth of nerve bundles and nerve mantle membranes, and inducing the nerve bundles to grow along the axial direction of the filling body (1) through the conductive pore channels and the conductive micropore channels of the filling body (1); simultaneously stimulating the muscles around the nerve mantle to slow the atrophy; based on electrical stimulation, the nerve cell differentiation induced by the nerve growth factor is accelerated, and the reconstruction of nerves is promoted.
10. The method of nerve repair of a conductive shape memory polymer device for nerve repair of claim 1, comprising the steps of:
(1) preparing a columnar shape memory polymer filling body (1), matching the initial length with the distance between two ends of a broken nerve, matching the diameter with the inner diameter of a broken nerve mantle, simultaneously compressing the filling body along the radial direction and the axial direction and placing the filling body at a nerve breakage position;
(2) the initial shape of the film of the flexible shape memory polymer coating body (3) is tubular, so that the initial length is matched with the distance between two ends of a broken nerve, and the diameter of the film is matched with the outer diameter of a broken nerve mantle; the pre-deformation treatment of radial expansion is carried out to form a tubular shape with an increased diameter;
(3) placing the columnar filler (1) subjected to compression pre-deformation treatment into the sleeve of the cladding body (3) subjected to pre-deformation treatment, and applying stimulation to recover the shapes of the columnar filler and the cladding body, so that the cladding body (3) tightly wraps the filler (1) and two ends of a nerve fracture, and the filler (1) is tightly contacted with the two ends of the nerve fracture;
(4) applying electrical stimulation to both ends of the cover body (3) and the filling body (1), thereby accelerating the growth of nerve bundles and nerve mantle and inducing the axial growth of the nerve bundles along the filling body (1) through the through channels and/or three-dimensional network-shaped void channels of the filling body (1); meanwhile, the muscles around the nerve mantle are stimulated to slow down atrophy, and the nerve cell differentiation induced by the nerve growth factor is accelerated based on the self electrical stimulation, so that the nerve reconstruction is promoted.
Technical Field
The invention belongs to the field of biomedical materials and implanted medical instruments, and particularly relates to a device for nerve repair, a preparation method and a repair method.
Background
The treatment and repair of nerve damage has long been one of the troublesome problems in the field of neurology. After peripheral nerves are damaged, the growth speed of the nerves is slow, and the damaged nerves are easy to adhere to peripheral tissues to form nerve scars. In addition, nerve damage can cause motor and sensory dysfunction of the functional areas it innervates, which in turn can lead to muscle atrophy, resulting in irreversible damage. Nerve transplantation and severed end suturing can effectively treat nerve injury, but the problems of limited donor source, unmatched diameter of donor and receptor nerves, immunological rejection, short repair distance and the like limit the clinical application of the nerve transplantation and severed end suturing. At present, excellent autonerve substitutes are searched, and meanwhile, the rapid and accurate regeneration of peripheral nerves is promoted in various ways, so that the method has important research value and clinical application prospect. Based on the strong self-repairing and regenerating capability of nerves, the nerve conduit can provide a specific microenvironment for nerve repair and regeneration, and further promotes nerve regeneration through the modes of nerve chemotaxis induction, neurotrophic effect and the like.
Electrical stimulation is effective in regulating and controlling cell adhesion, proliferation, migration and differentiation, and its role in the neural direction has been widely demonstrated, particularly in preventing atrophy of peripheral nerve muscles and promoting regeneration of peripheral nerves. Thus, nerve conduits are combined with electrical stimulation to stimulate and guide nerve growth and axon regeneration. Although there are patent documents on electrical stimulation-assisted nerve repair devices, these devices all suffer from different problems
Chinese patent publication No. CN 111408046 a discloses an electrical stimulation system for promoting nerve repair in vivo, which includes a nano-generator, a lead and an electrode. The nano generator is used for generating continuous current and voltage, and the continuous current and voltage are transmitted to the electrode through a lead, so that the aims of promoting damage repair and function reconstruction of nerve tissues and cells by electric stimulation are fulfilled. The electrode is made of gold and/or platinum through micro-nano processing on a polyimide flexible substrate. The device, while effective for the purpose of repairing damaged nerves, has a limited stimulation area. Meanwhile, the device is connected in vivo through a lead, which is not beneficial to long-distance transmission and flexible manufacturing in vivo.
Chinese patent publication No. CN 211634499U discloses a patterned graphene nerve conduit, which stores drugs in a hollow tube body to accelerate nerve repair, and induces nerve directional growth on the tube wall by using a groove-like pattern. The electrical conductivity of the graphene is utilized to promote the regeneration of nerves, the cost is high, and the processing technology is complex. With the release of the drug, the hollow area of the tube body becomes larger gradually, which is not favorable for the directional growth of the nerve.
Chinese patent publication No. CN 109793594 a discloses a block-structured conductive nerve conduit capable of spontaneous electrical stimulation and a method for preparing the same, which can spontaneously generate electrical stimulation by using glucose and oxygen in a human body to promote nerve growth. The conductive substrate film is made of carbon-based conductive materials such as carbon nanotubes and graphene, and is expensive. In addition, electrical stimulation, while accelerating nerve growth, does not modulate its directional growth.
Chinese patent publication No. CN 210354990U discloses a nerve conduit for repairing nerve defects. The nerve conduit induces the directional migration and growth of nerve tissue cells by arranging the longitudinally-communicated independent channel, increases the roughness of the inner wall of the pore, promotes the adhesion of the cells, and improves the repair effect of peripheral nerve defects. The size of the nerve is customized through 3D printing, and the raw material preparation time is long, so that the method has no wide adaptability.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a shape memory polymer device for nerve repair, a preparation method and a repair method in order to solve the problems that the treatment and repair cost of the current nerve injury is high, the treatment range is limited, the directional growth of the nerve is not facilitated and the like. The device with the shape memory effect is subjected to pre-deformation treatment, so that the nerve conduit and two ends of a broken nerve are more tightly wrapped, and the conduction of an electric signal in a nerve bundle is facilitated. The shape memory polymer device promotes adhesion, proliferation, migration, and differentiation of nerve cells using its electrical conductivity. The conductive micropores and the through conductive channels are used for inducing the directional growth of the nerves. The semi-interpenetrating polymer network structure formed by the shape memory polymer and the conducting polymer enables the conducting polymer to be embedded into a matrix, thereby realizing the conducting function and simultaneously increasing the conducting stability.
A conductive shape memory polymer device for nerve repair, comprising: a shape memory polymer filler and a shape memory polymer coating for coating the filler and both ends of the ruptured nerve; the flexible shape memory coating and the shape memory polymer filler have the characteristics of shape memory, electric conduction, biocompatibility and biodegradability at the same time.
Further, the channels for nerve repair growth inside the filling body are three-dimensional network-shaped pores and/or axial channels penetrating through the filling body.
Further, the flexible shape memory polymer coating and the shape memory polymer filling are in a semi-interpenetrating polymer network structure (IPN structure for short) formed by the shape memory polymer with biocompatibility and biodegradable characteristics and the conductive polymer, and the conductivity range of the shape memory polymer device for nerve repair is 10-7S/cm～104S/cm; the shape fixing rate of the shape memory polymer device is 70-99%; after being heated, the shape recovery rate is 20-99%, and the shape recovery temperature is 25-50 ℃.
Further, the shape memory polymer device has a biocompatibility rating of 0 or 1.
Further, the shape memory polymer filler with the three-dimensional network-shaped pore structure is a shape memory polymer foaming material.
Further, the flexible shape memory polymer coating and the shape memory polymer filler matrix material are: one or more of chitosan, collagen, polyurethane, polyvinyl alcohol, polylactic acid, polycaprolactone and polyglycolic acid; the conductive polymer is polyaniline.
Furthermore, the diameter of the micropores of the shape memory filling body with the three-dimensional network-shaped pore structure is 4-50 μm.
Furthermore, the diameter of the axial channel penetrating through the filling body is 50-150 μm and is uniformly distributed.
The preparation method of the conductive shape memory polymer device for nerve repair is characterized by comprising the following steps of:
(1) preparing a cylindrical shape memory polymer foam material as a shape memory polymer filler; preparing a film shape memory polymer coating;
(2) the channels penetrating along the radial direction are uniformly distributed on the cross section of the cylindrical shape memory polymer filler;
(3) putting the shape memory filler and the shape memory polymer coating processed in the step (2) into an aniline solvent to enable the shape memory filler and the shape memory polymer coating to fully swell; simultaneously, the cells in the shape memory polymer filler expand to open during the swelling process, thereby forming through micropore channels;
(4) introducing an oxidant solution into the swelled through filler and the shape memory polymer coating, wherein the oxidant and conductive polyaniline generated by polymerization of aniline are distributed at a certain depth on the surface layer of the coating and at a certain depth on the surfaces of pore channels and micropore channels of the filler respectively, and the filler matrix and the coating and the polyaniline form an interpenetrating polymer network structure respectively;
(5) drying to obtain the conductive shape memory polymer coating and the conductive shape memory polymer filling.
The nerve repair method of the conductive shape memory polymer device for nerve repair is characterized by comprising the following steps of:
(1) preparing a shape memory polymer filling body, matching the length of the filling body with the distance between two ends of a broken nerve, matching the diameter of the filling body with the inner diameter of a broken nerve mantle, fixing the filling body at a nerve breakage position, and contacting a nerve breakage surface;
(2) the flexible shape memory polymer coating film has the initial shape of a curl shape and is a plane after pre-deformation treatment; placing the nerve fracture site at the nerve fracture site, and applying stimulation to enable the nerve fracture site to be curled and restored, so that the filler and two ends of the nerve fracture are tightly coated;
(3) applying electrical stimulation to both ends of the coating body and the filling body so as to accelerate the growth of nerve bundles and nerve mantle membranes, and inducing the axial growth of the nerve bundles along the filling body through the conductive pore channels and the conductive micropore channels of the filling body; simultaneously stimulating the muscles around the nerve mantle to slow the atrophy; based on electrical stimulation, the nerve cell differentiation induced by the nerve growth factor is accelerated, and the reconstruction of nerves is promoted.
The nerve repair method of the conductive shape memory polymer device for nerve repair is characterized by comprising the following steps of:
(1) preparing a columnar shape memory polymer filling body, matching the initial length with the distance between two ends of a broken nerve, matching the diameter with the inner diameter of a broken nerve mantle, simultaneously compressing the filling body along the radial direction and the axial direction, and placing the filling body at a nerve breakage position;
(2) the flexible shape memory polymer coating film is tubular in initial shape, so that the initial length is matched with the distance between two ends of a broken nerve, and the diameter of the flexible shape memory polymer coating film is matched with the outer diameter of a broken nerve mantle; the pre-deformation treatment of radial expansion is carried out to form a tubular shape with an increased diameter;
placing the columnar filler subjected to the compression pre-deformation treatment in the cladding sleeve subjected to the pre-deformation treatment, and applying stimulation to recover the shapes of the columnar filler and the cladding sleeve, so that the cladding tightly wraps the filler and two ends of the nerve fracture, and the filler is tightly contacted with the two ends of the nerve fracture;
(4) applying electrical stimulation across the capsule and the filling body, thereby accelerating the growth of nerve bundles and nerve mantle and inducing axial growth of nerve bundles along the filling body through the through channels and/or three-dimensional network-like interstitial channels of the filling body; meanwhile, the muscles around the nerve mantle are stimulated to slow down atrophy, and the nerve cell differentiation induced by the nerve growth factor is accelerated based on the self electrical stimulation, so that the nerve reconstruction is promoted.
Compared with the prior art, the invention has the characteristics that: the shape memory effect of the shape memory polymer is utilized to enable the device to be implanted into an affected part in a smaller volume and to be tightly coated with two sections of broken nerves; inducing nerve bundles to grow along the radial direction of the filling body by utilizing the conductive channel and the conductive micro-gap channel of the filling body, and stimulating muscles around the nerve mantle to slow down the cachexia; based on self electrical stimulation, the nerve cell differentiation induced by the nerve growth factor is accelerated, and the nerve reconstruction is promoted.
Compared with the prior art, the invention has the following advantages:
1. the preparation process of the shape memory polymer device for nerve repair provided by the invention is not influenced by the environmental temperature, and is simple, low in equipment requirement, less in pollution and low in cost.
2. By utilizing the principle of shape memory effect, the shape memory polymer device is compressed in volume through predeformation and is implanted into an affected part in a smaller volume, so that the pain of a patient is reduced, and the healing time is shortened; the filler is closely contacted with two ends of the nerve fracture by thermally driving shape recovery, which is beneficial to implementation of electrical stimulation.
3. The micropore channel and the conductive path in the filling body are utilized to accelerate nerve repair and induce the directional growth of nerves.
4. The conductive polymer is introduced into the shape memory polymer device, so that the shape memory polymer device has weak electric property, conforms to the physiological current of a human body, is favorable for the growth of nerve cells, and further accelerates the nerve repair.
5. The device satisfies the required electro photoluminescence of nerve growth, possesses good biocompatibility and mechanical strength that traditional nerve conduit possessed simultaneously, and the directional growth of induced nerve simultaneously, micropore passageway and conductive path are fit for the cell growth, are favorable to peripheral nerve regeneration.
Drawings
FIG. 1 is a top view of the shape memory fill of the present invention.
FIG. 2 is a front view of the shape memory fill of the present invention.
FIG. 3 is a schematic view of the shape-memory tubular cover of the present invention.
FIG. 4(a) is a schematic view of the shape memory crimp cladding of the present invention.
FIG. 4(b) is a schematic view of the pre-deformed shape memory crimp cladding of the present invention.
Detailed Description
The invention will be further described with reference to the following figures and specific examples, but the scope of the invention is not limited thereto.
The conductive shape memory polymer device for nerve repair of the present invention, as shown in fig. 1, fig. 2 and fig. 3, comprises a shape memory polymer filler 1, and a shape memory polymer coating 3 for coating the filler 1 and two ends of a broken nerve; the shape memory polymer filler 1 is internally provided with a channel for nerve repair growth, and the flexible shape memory coating 3 and the shape memory polymer filler 1 simultaneously have the characteristics of shape memory, electric conduction, biocompatibility and biodegradability. The channels for nerve repair growth inside the filling body 1 are three-dimensional network-shaped pores and/or axial channels penetrating through the filling body 1.
The flexible shape memory polymer coating body 3 and the shape memory polymer filling body 1 are in a semi-interpenetrating polymer network structure formed by shape memory polymer with biocompatibility and biodegradable characteristics and conductive polymer, and the conductivity range of the shape memory polymer device for nerve repair is 10-7S/cm～104S/cm; the shape fixing rate of the shape memory polymer device is 70-99%; after being heated, the shape recovery rate is 20-99%, and the shape recovery temperature is 25-50 ℃.
Wherein, the shape memory polymer filler 1 with three-dimensional network-shaped pore structure is a shape memory polymer foaming material. The flexible shape memory polymer coating body 3 and the shape memory polymer filling body 1 are made of the following base materials: one or more of chitosan, collagen, polyurethane, polyvinyl alcohol, polylactic acid, polycaprolactone and polyglycolic acid; the conductive polymer is polyaniline. The diameter of the micropores of the shape memory filler 1 with the three-dimensional network-shaped pore structure is 4-50 μm. The diameter of the axial channel penetrating through the filling body (1) is 50-150 μm and is uniformly distributed.
The nerve repair method of the conductive shape memory polymer device for nerve repair is characterized by comprising the following steps of:
(1) preparing a shape memory polymer filling body (1), matching the length with the distance between two ends of a broken nerve and matching the diameter with the inner diameter of a broken nerve mantle, fixing the filling body at the position of the nerve break and contacting the broken surface of the nerve.
(2) The initial shape of the flexible shape memory polymer coating (3) is curl-shaped, as shown in fig. 4(a), and the flexible shape memory polymer coating is planar after being subjected to pre-deformation treatment; it is placed at the nerve rupture site and a stimulus is applied to cause the nerve rupture site to recover by curling, thereby tightly covering the obturator (1) and the two ends of the nerve rupture site, as shown in fig. 4 (b).
(3) Applying electrical stimulation to two ends of the coating body (3) and the filling body (1) so as to accelerate the growth of nerve bundles and nerve mantle membranes, and inducing the nerve bundles to grow along the axial direction of the filling body (1) through the conductive pore channels and the conductive micropore channels of the filling body (1); simultaneously stimulating the muscles around the nerve mantle to slow the atrophy; based on electrical stimulation, the nerve cell differentiation induced by the nerve growth factor is accelerated, and the reconstruction of nerves is promoted.
Or the nerve repair is carried out by adopting the following mode, which specifically comprises the following steps:
(1) preparing a columnar shape memory polymer filling body (1), matching the initial length with the distance between two ends of a fractured nerve, matching the diameter with the inner diameter of a mantle of the fractured nerve, simultaneously compressing the filling body along the radial direction and the axial direction and placing the filling body at the position of the nerve fracture.
(2) The initial shape of the film of the flexible shape memory polymer coating body (3) is tubular, so that the initial length is matched with the distance between two ends of a broken nerve, and the diameter of the film is matched with the outer diameter of a broken nerve mantle; the radially expanded pre-deformation treatment is tubular with an increased diameter.
(3) The columnar filler (1) subjected to compression pre-deformation treatment is placed in the sleeve of the cladding body (3) subjected to pre-deformation treatment, and stimulation is applied to enable the columnar filler (1) and the cladding body (3) to recover in shape, so that the cladding body (3) tightly wraps the filler (1) and two ends of the nerve fracture, and the filler (1) is tightly contacted with the two ends of the nerve fracture.
(4) Applying electrical stimulation to both ends of the cover body (3) and the filling body (1), thereby accelerating the growth of nerve bundles and nerve mantle and inducing the axial growth of the nerve bundles along the filling body (1) through the through channels and/or three-dimensional network-shaped void channels of the filling body (1); meanwhile, the muscles around the nerve mantle are stimulated to slow down atrophy, and the nerve cell differentiation induced by the nerve growth factor is accelerated based on the self electrical stimulation, so that the nerve reconstruction is promoted.
The first embodiment is as follows: preparation method of shape memory polymer device for nerve repair
The method comprises the steps of preparing a columnar foaming material and a curled coating body 3 by taking chitosan as a raw material, processing through pore channels which are uniformly distributed in the radial direction of the foaming material, and placing the foaming material and the coating body 3 in an aniline solvent to enable the foaming material and the coating body 3 to be fully swelled to form a through micropore channel. After 2 hours, putting the mixture into a peroxyacetic acid solution for oxidative polymerization to obtain the conductive polyaniline, and swelling and polymerizing the conductive polyaniline within 10 minutes. Drying the molecular composite material distributed with polyaniline macromolecular chains. And (3) wrapping the cylindrical foaming material by using the shape memory flexible polymer to ensure that the cylindrical foaming material is fully contacted with the flexible matrix. The material is dried to obtain the conductive shape memory polymer coating 3 and the conductive shape memory polymer filling.
Example two: preparation method of shape memory polymer device for nerve repair
The method comprises the steps of preparing a columnar foaming material and a curled coating body 3 by using polycaprolactone as a raw material, processing through pore channels which are uniformly distributed in the radial direction of the foaming material, and placing the foaming material and the coating body 3 in an aniline solvent to enable the foaming material and the coating body to be fully swelled to form a through micropore channel. After 8 hours, putting the mixture into a sodium hypochlorite solution for oxidation polymerization to obtain the conductive polyaniline, and swelling and polymerizing the conductive polyaniline within 15 minutes. Drying the molecular composite material distributed with polyaniline macromolecular chains. And (3) wrapping the cylindrical foaming material by using the shape memory flexible polymer to ensure that the cylindrical foaming material is fully contacted with the flexible matrix. The material is dried to obtain the conductive shape memory polymer coating 3 and the conductive shape memory polymer filling.
Example three: preparation method of shape memory polymer device for nerve repair
The method comprises the steps of preparing a columnar foaming material and a tubular coating body 3 by taking polyurethane as a raw material, processing through pore channels which are uniformly distributed in the radial direction of the foaming material, and placing the foaming material and the coating body 3 in an aniline solvent to enable the foaming material and the coating body 3 to be fully swelled to form a through micropore channel. After 12 hours, putting the mixture into a sodium dichromate solution for oxidation polymerization to obtain the conductive polyaniline, and completing swelling polymerization within 30 minutes. Drying the molecular composite material distributed with polyaniline macromolecular chains. And (3) wrapping the cylindrical foaming material by using the shape memory flexible polymer to ensure that the cylindrical foaming material is fully contacted with the flexible matrix. The material is dried to obtain the conductive shape memory polymer coating 3 and the conductive shape memory polymer filling.
Example four: preparation method of shape memory polymer device for nerve repair
Preparing a columnar foaming material and a curled coating body 3 by taking polylactic acid as a raw material, processing through pore channels which are uniformly distributed in the radial direction of the foaming material, and placing the foaming material and the coating body 3 in an aniline solvent to enable the foaming material and the coating body 3 to be fully swelled to form a through micropore channel. After 6 hours, putting the mixture into a complex acid solution for oxidative polymerization to obtain the conductive polyaniline, and completing swelling polymerization within 25 minutes. Drying the molecular composite material distributed with polyaniline macromolecular chains. And (3) wrapping the cylindrical foaming material by using the shape memory flexible polymer to ensure that the cylindrical foaming material is fully contacted with the flexible matrix. The material is dried to obtain the conductive shape memory polymer coating 3 and the conductive shape memory polymer filling.
Example five: preparation method of shape memory polymer device for nerve repair
The method comprises the steps of preparing a columnar foaming material and a tubular coating body 3 by using polyvinyl alcohol as a raw material, processing through pore channels which are uniformly distributed in the radial direction of the foaming material, and placing the foaming material and the coating body 3 in an aniline solvent to enable the foaming material and the coating body 3 to be fully swelled to form a through micropore channel. After 4 hours, putting the mixture into a potassium perborate solution for oxidation polymerization to obtain the conductive polyaniline, and swelling and polymerizing the conductive polyaniline within 15 minutes. Drying the molecular composite material distributed with polyaniline macromolecular chains. And (3) wrapping the cylindrical foaming material by using the shape memory flexible polymer to ensure that the cylindrical foaming material is fully contacted with the flexible matrix. The material is dried to obtain the conductive shape memory polymer coating 3 and the conductive shape memory polymer filling.
Example six: method of repairing shape memory polymer devices for nerve repair
Preparing a columnar shape memory chitosan filling body, matching the initial length with the distance between two ends of a broken nerve, matching the diameter with the inner diameter of a broken nerve mantle, simultaneously compressing the filling body along the radial direction and the axial direction, and placing the filling body at the position of the nerve breakage. The tubular chitosan coating 3 matched with the length of the broken nerve is pre-deformed by radial expansion to be in a tubular shape with an increased diameter. The columnar filling body subjected to the compression pre-deformation treatment is placed in the sleeve of the cladding body 3 subjected to the diameter expansion pre-deformation treatment, and stimulation is applied to enable the shape of the columnar filling body and the sleeve to recover. So that the packing body 3 tightly coats the packing body and the two ends of the nerve rupture, and the packing body is tightly contacted with the two ends of the nerve rupture. Electrical stimulation is applied to the two ends of the coating body 3 and the filling body, so that the growth of nerve bundles and a nerve mantle is accelerated, and the nerve bundles are induced to grow along the radial direction of the filling body through the conductive pore channels and the conductive micro-gap channels of the filling body; at the same time, the muscles around the nerve mantle are stimulated to slow the atrophy. Based on self electrical stimulation, the nerve cell differentiation induced by the nerve growth factor is accelerated, and the nerve reconstruction is promoted.
Example seven: method of repairing shape memory polymer devices for nerve repair
Preparing shape memory polycaprolactone filler, matching the length with the distance between two ends of the broken nerve and the diameter with the inner diameter of the broken nerve mantle, fixing the filler at the position of the broken nerve and contacting the broken surface of the nerve. The initial shape of the shape memory polycaprolactone coating body 3 film is curl-shaped, and the film is planar after pre-deformation treatment. The nerve fracture is placed at the nerve fracture position, and the stimulation is applied to enable the nerve fracture to be curled and restored, so that the filler and the two ends of the nerve fracture are tightly coated. Applying electrical stimulation to the two ends of the coating body 3 and the filling body so as to accelerate the growth of nerve bundles and a nerve mantle, and inducing the radial growth of the nerve bundles along the filling body through the conductive pore channels and the conductive micropore channels of the filling body; at the same time, the muscles around the nerve mantle are stimulated to slow the atrophy. Based on self electrical stimulation, the nerve cell differentiation induced by the nerve growth factor is accelerated, and the nerve reconstruction is promoted.
Example eight: method of repairing shape memory polymer devices for nerve repair
Preparing a columnar shape memory polylactic acid filling body, matching the initial length with the distance between two ends of a broken nerve, matching the diameter with the inner diameter of a broken nerve mantle, simultaneously compressing the filling body along the radial direction and the axial direction, and placing the filling body at the position of the nerve breakage. The shape memory polylactic acid coating body 3 is in a curled shape in the initial shape of the film and is in a plane shape after being subjected to pre-deformation treatment. The nerve fracture is placed at the nerve fracture position, and the stimulation is applied to enable the nerve fracture to be curled and restored, so that the filler and the two ends of the nerve fracture are tightly coated. The columnar filler subjected to the compression pre-deformation treatment is placed on the plane of the cladding body 3 subjected to the pre-deformation treatment, and the shape of the columnar filler and the plane of the cladding body is recovered by applying stimulation, so that the cladding body 3 tightly wraps the filler and two ends of the nerve fracture, and the filler is tightly contacted with the two ends of the nerve fracture. Electrical stimulation is applied to the two ends of the coating body 3 and the filling body, so that the growth of nerve bundles and a nerve mantle is accelerated, and the nerve bundles are induced to grow along the radial direction of the filling body through the conductive pore channels and the conductive micro-gap channels of the filling body; at the same time, the muscles around the nerve mantle are stimulated to slow the atrophy. Based on self electrical stimulation, the nerve cell differentiation induced by the nerve growth factor is accelerated, and the nerve reconstruction is promoted.
The present invention is not limited to the above-described embodiments, and any obvious improvements, substitutions or modifications can be made by those skilled in the art without departing from the spirit of the present invention.