CN113398325A - Fibrous membrane for enhancing screw stability and inducing bone regeneration and preparation method thereof - Google Patents

Abstract

The invention belongs to the technical field of biological materials, and particularly relates to a fibrous membrane for enhancing the stability of a screw and inducing bone regeneration and a preparation method thereof. A preparation method of a fiber membrane mainly comprises the steps of preparing raw materials including polyhydroxyalkanoate, graphene oxide and polyvinyl alcohol, preparing a hollow porous, oriented, ordered and disordered fiber structure through an electrostatic spinning technology, and fixing an osteogenesis inducing component on a fiber through a coaxial or self-assembly technology. The fiber prepared by the method can be formed into a film shape, a cylinder shape and a screw sleeve shape, so as to solve the technical problems of insecure screw fixation and delayed or nonunion of fracture healing in the prior orthopedic surgery technology. The fibrous membrane can realize controllable in vivo degradation according to requirements without taking out the fibrous membrane after secondary operation.

Description

Fibrous membrane for enhancing screw stability and inducing bone regeneration and preparation method thereof

Technical Field

The invention belongs to the technical field of biological materials, and particularly relates to a fibrous membrane for enhancing the stability of a screw and inducing bone regeneration and a preparation method thereof.

Background

The common injury of human beings in fracture refers to a disease that bone is partially or completely broken due to trauma or pathology. In the current internal fixation treatment of fracture, when a patient with fracture is subjected to surgical incision reduction and steel plate screw internal fixation, the current clinically used screws sometimes cannot meet the requirements of fixing all fracture blocks, and the screws can partially or completely loosen due to multiple times of screw passing in and out, screw replacement or osteoporosis during the internal fixation operation of fracture, so that the internal fixation fails to cause a series of complications, the strength and the effect of the internal fixation are influenced, the failure of the internal fixation operation can be possibly caused, and no good solution exists at present. Inspired by condoms, if a condom is also worn on the screw and then screwed into the loose duct, the stability of screw fixation may be instantly increased.

The electrostatic spinning technology is a high-efficiency low-consumption nano fiber preparation technology, and is characterized in that high-voltage static electricity is applied between a spray head filled with polymer solution and a receiving device, so that the solution generates an electric field force opposite to surface tension under the action of a high-voltage electric field, the solution is driven to stretch into a Taylor cone at the tail end of the spray head, when the electric field force is large enough, liquid drops at the Taylor cone can overcome the surface tension to generate a jet flow, the jet flow is rapidly attenuated in high-speed oscillation, a solvent is rapidly volatilized, and finally nano-micron-diameter superfine fibers are formed. The diameter of the electrospun fiber is usually between tens of nanometers and several micrometers, the electrospun fiber has a staggered grid structure on a microstructure, has controllable mechanical properties and high friction, and simultaneously, the fiber arrangement with high porosity and pore size can simulate the structure of extracellular matrix, so that the cell adhesion, growth and differentiation are promoted.

Poly (3-hydroxybutyrate-co-4-hydroxybutyrate), P34HB, has good mechanical properties besides good biocompatibility, biodegradability and spinnability, and P34HB electrospun fiber material can partially repair SD rat skull defects, but has poor hydrophilicity, so that the application of the material in biomedicine is limited. Graphene Oxide (GO) has better mechanical strength and hydrophilicity due to special sp2 bonding and a hexagonal carbon structure, can effectively regulate and control cell behaviors, provides positioning points for cells and induces osteogenic differentiation of mesenchymal stem cells, can be used as a coating material to improve the compatibility between titanium alloy internal fixation and bone tissues, and in addition, Graphene-based materials have good antibacterial performance and can further reduce the infection risk of internal fixation implants, but GO does not have spinnability and can be electrospun into nano-micron fibers to play a role by being compounded with other materials. Polyethylene glycol (PEG) is a hydrophilic biomaterial, has good biocompatibility and spinnability and is widely applied to the field of biopharmaceuticals, a composite fiber material with P34HB has been proved to promote bone regeneration, and Polyethylene glycol is used as a binder to enable alumina powder to form a solid, which shows good metal adhesion performance.

Disclosure of Invention

In order to overcome the technical problems, the invention provides a fibrous membrane for enhancing the stability of a screw and inducing bone regeneration and a preparation method thereof. The fiber prepared by the method can be formed into a film shape, a cylinder shape and a screw sleeve shape, so as to solve the technical problems of insecure screw fixation and delayed or nonunion of fracture healing in the prior orthopedic surgery technology. The fibrous membrane can realize controllable in vivo degradation according to requirements without taking out the fibrous membrane after secondary operation.

In order to achieve the above purpose, the technical scheme provided by the invention is as follows:

a preparation method of a nano/micron fiber membrane comprises the following steps:

s1: dispersing graphene oxide in dichloromethane or six-fu isopropanol to prepare a solution, and dissolving polyhydroxyalkanoate and polyethylene glycol in the solution to obtain a solution A;

s2: taking an injector and an injection needle head, setting positive voltage, negative voltage, temperature, injection speed and receiving distance by using a tin foil paper roller as a receiver, preparing a film, drying and sterilizing.

Preferably, in step S1, the polyhydroxyalkanoate is any one of a first-generation Polyhydroxybutyrate (PHB), a second-generation hydroxybutyrate/valerate copolyester (PHBV), a third-generation hydroxybutyrate hexanoate copolyester (phbhrx) or a fourth-generation poly 3-hydroxybutyrate/4-hydroxybutyrate copolymer (P34 HB).

Preferably, in step S1, the solution a contains 7% of polyhydroxyalkanoate, 5% of polyethylene glycol, and 1mg/mL of graphene oxide per 10mL of dichloromethane or six-Formica Fusca isopropanol.

Preferably, in step S2, the specification of the syringe is 10 mL; the injection needle is a 23G injection needle.

Preferably, in step S2, the positive voltage is 10kV, the negative voltage is 10kV, the temperature is 37 ℃, the bolus velocity is 0.3mm/min, and the receiving distance is 15-20 cm.

Preferably, in step S2, the drying is carried out for 48 hours after placing in a vacuum drier, and the residual organic solvent is evaporated.

The invention also aims to provide a preparation method of the hollow porous nano/micron fiber membrane, which comprises the following steps:

(1) dispersing graphene oxide in dichloromethane or six-fu isopropanol to prepare a solution, and dissolving polyhydroxyalkanoate and polyethylene glycol in the solution to obtain a solution A;

(2) dissolving polyethylene glycol and osteogenic active peptide or natural small molecular compound in water to prepare solution B;

(3) respectively loading solution A and solution B into an injector, using a coaxial nozzle to take the solution A as a shell layer and the solution B as a core layer, using a silver paper roller as a receiver, setting positive voltage, negative voltage, temperature and injection speed, respectively, receiving distance to prepare a fiber film, placing the fiber film into an aqueous solution, performing ultrasonic oscillation to obtain a micron fiber film with a hollow porous structure, and performing vacuum drying and sterilization.

Another object of the present invention is to provide a method for preparing an ordered-disordered hollow porous nano/micro fiber membrane, which comprises the following steps:

(1) dispersing graphene oxide in dichloromethane or six-fu isopropanol to prepare a solution, and dissolving polyhydroxyalkanoate and polyethylene glycol in the solution to obtain a solution A;

(2) dissolving polyethylene glycol in water to obtain a solution B;

(3) respectively loading solution A and solution B into an injector, using a coaxial nozzle to take the solution A as a shell layer and the solution B as a core layer, using a high-speed orientation device as a receiver, setting positive voltage, negative voltage, temperature and injection speed respectively, receiving distance to prepare a fiber film, placing the fiber film into an aqueous solution, performing ultrasonic oscillation to obtain a nano/micron fiber film with an ordered-disordered hollow porous structure, repeatedly soaking the fiber film into a solution with osteogenic active peptide or a natural small molecular compound, and performing vacuum drying and sterilization.

Preferably, in step (3), the osteogenic active peptide or natural small molecule compound comprises: Arg-Gly-Asp (RGD) peptide, collagen mimetic peptide P-15, heparin-binding peptide, bone morphogenetic protein-7 derived peptide, bone morphogenetic protein-2 derived peptide, glucagon-like peptide-1 (GLP-1), Osteogenic Growth Peptide (OGP), parathyroid hormone-related peptide (PTHrP-1), QK peptide, Prominin-1derived peptide (PR 1P); any one or more of quercetin, puerarin, resveratrol, curcumin, epigallocatechin gallate (EGCG), and berberine.

Preferably, in step (3), the size of the syringe is 5 mL.

Preferably, in the step (3), the positive voltage is 15kV, the negative voltage is 5kV, the temperature is 37 ℃, the bolus injection speed is 0.5/0.1mm/min, and the receiving distance is 15-20 cm; the rotating speed of the receiving device is 2000 r/min.

Preferably, in step (3), the dried mixture is placed in a vacuum drier for drying for 48 hours, so that the residual organic solvent is evaporated.

The invention also aims to provide a nano/micro fiber membrane prepared by the preparation method.

Preferably, the nano/micron fibers are in the shape of a film or in the shape of a hollow or solid cylinder or in the shape of a screw sleeve.

Preferably, the nano/micro fibers have a hollow porous microstructure.

The invention also aims to provide a functional absorbable orthopedic screw sleeve which is prepared from the cellulose membrane or nano/micro fibers.

The invention also aims to provide a preparation method of the functional absorbable orthopedic screw sleeve, which comprises the following steps:

according to the requirements of the diameter and the length of the clinical orthopedic screw, the fiber membranes with the same thickness are made into sleeve shapes with different diameters and different lengths by using the intelligent rolling shaft and are integrated with the screw body.

The screw sleeve is matched with the diameter and the length of the screw for clinical orthopedics department, and is tightly combined on the surface of the screw body, so that the initial test stability and the anti-pull-out force of the screw in the operation can be effectively increased.

Preferably, the functional absorbable orthopedic screw sleeve can also be prepared by connecting an orthopedic metal screw with an electrospinning receiver and obtaining an integrated structure of the screw and the screw sleeve by one-step molding.

Compared with the prior art, the invention has the technical advantages that:

(1) the fiber membrane provided by the invention is prepared by taking biodegradable polyhydroxyalkanoate with biocompatibility and graphene oxide as main materials through an electrostatic spinning technology. The fiber has a hollow porous or oriented structure, and the fiber membrane prepared by the method has good mechanical property, and can effectively enhance the initial stability and axial pull-out resistance of the screw after being combined with the orthopedic screw, thereby solving the clinical problem of screw looseness in operation.

(2) According to the invention, by adopting a coaxial electrostatic spinning technology and combining the advantages of three materials of graphene oxide, polyhydroxyalkanoate and polyethylene glycol, a hollow porous fiber membrane with controlled slow-release components is constructed, the screw stability and axial pullout resistance in screw operation are increased immediately and maintained, fracture healing is promoted, and an effective solution is provided for clinical screw loosening.

(3) Meanwhile, an osteogenesis inducing component is added into the fiber with a hollow porous microstructure, so that the biostability is increased, and the generation of new bones is induced, and the technical problems of insecure screw fixation, delayed fracture healing, deformed healing or nonunion of fractures in the clinical practice at present are solved; it is slowly released in the process of bone repair, promotes fracture healing, and has wide application prospect in the fields of biological medicine, particularly orthopedics.

(4) The screw sleeve is prepared by preparing a solution from biodegradable material polyhydroxyalkanoate, polyethylene glycol and graphene oxide, and spinning the material into a nanoscale membrane package, a three-dimensional sleeve shape and a screw body under a high-voltage electric field by using an electrostatic spinning technology. The adopted polyhydroxyalkanoate, polyethylene glycol and graphene oxide materials can be completely degraded, no acid metabolite is generated, aseptic inflammatory reaction complications generated by the current clinical internal fixation materials are effectively avoided, and the graphene oxide has good biological activity and biomechanical property. The screw has better early biological stability, and the common problem of screw loosening after operation is prevented.

Furthermore, the functional screw sleeve is prepared by adding osteogenic active peptide or natural small molecular compound into solution of polyhydroxyalkanoate, polyethylene glycol and graphene oxide, and spinning the material into nano-scale fibrous membrane, hollow or solid cylinder and screw sleeve under high-voltage electric field by using electrostatic spinning technology. In the process of material absorption, the osteogenic active peptide or the natural small molecular compound has the osteogenic induction effect, and promotes fracture healing and bone regeneration.

(5) The hollow porous fiber prepared by the invention can regulate and control the size of pores on the fiber filament so as to control the release speed of osteogenic components.

Drawings

FIG. 1: the fibrous membrane made in example 1;

FIG. 2: electron micrographs of the fiber film of example 1;

FIG. 3: the fibrous membrane made in example 2;

FIG. 4: example 2 micro pore size structure diagram of fibrous membrane; wherein, (4-1) is a hollow structure diagram of the fiber; (4-2) is a structure diagram of the surface porosity of the fiber.

FIG. 5: the fibrous membrane made in example 3;

FIG. 6: example 3 microstructure of fiber arrangement of fibrous membrane; wherein (6-1) is a fiber orientation arrangement diagram; and (6-2) is a fiber disordered-ordered arrangement diagram.

FIG. 7: preparation scheme for example 4; wherein, 1 is solution A, 2 is solution B, 3 is a fibrous membrane, and 4 is a screw.

FIG. 8: screw sleeve shape of example 4;

FIG. 9: mechanical property profile of the fibrous membrane of example 5; wherein a is a stress-displacement diagram; b is an elastic modulus graph; c is an elongation chart; d is a maximum tensile strength graph;

FIG. 10: pull-out curves versus pull-out forces for example 5; wherein a is a drawing force curve of the screw under the conditions of primary axial drawing force, secondary axial drawing force and complete loosening in an in-vitro standard test piece; b, under the condition of partial looseness, combining all the groups of condom screws and screwing the combined condom screws into the original nail channel to carry out extraction force test to obtain an extraction force curve; c, under the condition of complete looseness, combining each group of condoms and screws, screwing the condoms into the screw channel, and carrying out extraction force test to obtain an extraction force curve; d is the comparison of the primary axial extraction force, the secondary axial extraction force and the extraction force under the condition of complete looseness in the standard test piece; e is the comparison of the axial withdrawal force of each group of condoms and the combined screw under the condition of partial looseness; f is the comparison of the axial withdrawal force of each group of condoms and the combined screw under the condition of complete looseness;

FIG. 11: the in vitro anti-pull-out test result, wherein a is a schematic operation diagram; b is a schematic diagram of the positions of the arrow nail path and the fracture line; c is a use schematic diagram of a conventional group of screws; d is a schematic diagram of the use of the experimental group of screws; e is a schematic view of the non-loose group fracture; f is a schematic diagram after the non-loose group heals; g is a schematic diagram of a checking result of the CBCT of the non-loose group; h is a fracture schematic diagram of the safety sleeve; i is a schematic diagram after the safety sleeve is healed; j is a schematic diagram of the inspection result of the safety kit CBCT; k is a complete loosening group fracture schematic diagram; l is a schematic diagram after the complete loosening group is healed; and m is a schematic diagram of the CBCT inspection result of the complete loose group.

The invention will now be further illustrated with reference to the accompanying drawings and examples:

Detailed Description

The present invention will be described below with reference to specific examples to make the technical aspects of the present invention easier to understand and grasp, but the present invention is not limited thereto. The experimental methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.

Example 1

A preparation method of a fiber membrane comprises the following steps:

(1) preparing a solution: carrying out ultrasonic dispersion on graphene oxide in 10mL of dichloromethane for 3 hours in the dark to prepare a solution with a w/v gradient of 1mg/mL, dissolving 0.7g P34HB and 0.5g of polyethylene glycol 4000 in the solution, and adding six-fourteen-compound isopropanol to 10mL to obtain a solution A (the solution A represents 10mL of six-fourteen-compound isopropanol and contains 7% of P34HB, 5% of polyethylene glycol 4000 and 1mg/mL of graphene oxide);

(2) electrospinning: taking a 10ml injector and a 23G injection needle head, using a tin foil paper roller as a receiver, setting a positive voltage of about 10kV, a negative voltage of 10kV, a temperature of 37 ℃, an injection speed of 0.3mm/min and a receiving distance of 15-20cm, obtaining a film, and then placing the film in a vacuum drier for drying for 48 hours to evaporate residual organic solvent; sterilizing by double-sided ultraviolet irradiation for 4h to obtain fiber membrane (visual image as figure 1), and observing fiber structure with scanning electron microscope as figure 2.

Example 2

A preparation method of a hollow porous fiber membrane comprises the following steps:

(1) preparing a solution: carrying out light-shielding ultrasonic dispersion on graphene oxide in 10mL of six-happiness isopropanol for 3 hours to prepare a solution with a w/v gradient of 1mg/mL, dissolving 0.7g P34HB and 0.5g of polyethylene glycol 4000 in the solution, adding six-happiness isopropanol to 10mL to obtain a solution A, and dissolving 0.5g of polyethylene glycol 4000 and osteogenic active peptide in 10mL of water to obtain a solution B;

(2) electrospinning: respectively installing solution A and solution B on 2 5ml injectors, using a coaxial nozzle, using the solution A as a shell layer and the solution B as a core layer, using a tin foil paper roller as a receiver, setting a positive voltage of about 15kV, a negative voltage of 5kV, a temperature of 37 ℃, an injection speed of 0.5/0.1mm/min respectively, a receiving distance of 15-20cm, obtaining a fiber film, placing the fiber film in an aqueous solution, sufficiently oscillating the fiber film by using an ultrasonic oscillator to obtain a micron fiber film with a hollow porous structure, and drying the micron fiber film in a vacuum dryer for 48 hours to evaporate residual organic solvent; sterilizing by double-sided ultraviolet irradiation for 4h to obtain fiber membrane (visual image as figure 3), and observing fiber structure with scanning electron microscope as figure 4, wherein (4-1) is hollow structure of fiber; (4-2) is a structure diagram of the surface porosity of the fiber.

Example 3

A preparation method of an ordered-unordered hollow porous fiber membrane comprises the following steps:

(1) preparing a solution: carrying out ultrasonic dispersion on graphene oxide in 10mL of six-happiness isopropanol for 3 hours in the dark to prepare a solution with a w/v gradient of 1mg/mL, dissolving 0.7g P34HB and 0.5g of polyethylene glycol 4000 in the solution, and adding the six-happiness isopropanol to 10mL to obtain a solution A (the solution A represents 10mL of six-happiness isopropanol and contains 7% of P34HB, 5% of polyethylene glycol 4000 and 1mg/mL of graphene oxide);

(2) electrospinning: respectively loading solution A and solution B into an injector, using a coaxial nozzle to take the solution A as a shell layer and the solution B as a core layer, using a high-speed orientation device as a receiver, setting a positive voltage of about 15kV, a negative voltage of 5kV, a temperature of 37 ℃, an injection speed of 0.5/0.1mm/min respectively, a receiving distance of 15-20cm to prepare a fiber film, placing the fiber film into an aqueous solution, performing ultrasonic oscillation to obtain a nano/micron fiber film with an ordered-disordered hollow porous structure, repeatedly soaking the fiber film into a solution with a natural small molecular compound, drying in a vacuum dryer for 48 hours, performing double-sided ultraviolet irradiation for 4 hours to sterilize, obtaining the fiber film (visual image as figure 5), observing the ordered-disordered fiber structure by using a scanning electron microscope as figure 6, wherein (6-1) is a fiber orientation arrangement image; and (6-2) is a fiber disordered-ordered arrangement diagram.

Example 4

(1) Preparing a solution: carrying out light-shielding ultrasonic dispersion on graphene oxide in 10mL of dichloromethane for 3 hours to prepare a solution with a w/v gradient of 1mg/mL, dissolving 0.7g P34HB and 0.5g of polyethylene glycol 4000 in the solution, adding dichloromethane to 10mL to obtain a solution A, and dissolving 0.5g of polyethylene glycol 4000 and an osteogenic active peptide in 10mL of water to obtain a solution B;

(2) preparing a screw sleeve: connecting the orthopedic metal screw with a receiver, respectively installing the solution A and the solution B in 2 5mL injectors, using a coaxial nozzle, taking the solution A as a shell layer and the solution B as a core layer, setting a positive voltage of about 15kV, a negative voltage of 5kV, a temperature of 37 ℃, injecting speeds of 0.5/0.1mm/min respectively, a receiving distance of 15-20cm, drying in a vacuum drying machine for 48 hours after obtaining a screw-screw sleeve body, and evaporating residual organic solvent; sterilizing by double-sided ultraviolet irradiation for 4 h. The process diagram is shown in fig. 7.

The produced screw sleeve is shown in figure 8, and the screw sleeve is a functional absorbable orthopedic screw sleeve, and comprises a screw and a screw sleeve made of a bioabsorbable material. The screw sleeve is sleeved on the screw body part like a safety sleeve. The screw sleeve is prepared by preparing polyhydroxy fatty acid ester, polyethylene glycol and graphene oxide into a solution, simultaneously adding osteogenic active peptide into the solution, and spinning the material into a nano-scale three-dimensional sleeve shape by utilizing an electrostatic spinning technology and using a coaxial nozzle under a high-voltage electric field. In the process of material absorption, the release of the osteogenic active peptide has an osteogenesis inducing effect, can increase the biological stability and simultaneously induce the generation of new bones, and avoids the technical problems of insecure screw fixation, delayed fracture healing, deformity healing or fracture nonunion in the clinical at present.

Example 5

With reference to the method of example 1, the following raw materials were used, respectively, with the experimental procedure unchanged: p34HB and PEG were added with graphene oxide at different ratios (0.5-2.5) to prepare films having a size of 10mm × 15mm × 0.14mm and an effective stretching length of 10mm (n ═ 5for ear group); wherein, P34HB is simply (P), PEG is added to be (P-P), and graphene oxide is added to be (P-P-G); and (3) preparing a product: p, P-P, P-P-G0.5, P-P-G1, P-P-G1.5, P-P-G2 and P-P-G2.5.

Evaluation of the effects:

1. mechanical Property test

The experimental method comprises the following steps: the product of example 5 was tested for mechanical properties including stress-displacement relationship, modulus of elasticity, elongation, and maximum tensile strength.

Tensile testing (100N sensor, tensile speed 1mm/min) with a universal mechanical tester (Tilt technologies, science and technology Co., Ltd., China); the tensile strength and Young's modulus were obtained.

The results are shown in fig. 9, and the stress-displacement relationship of each group of thin film materials is measured by a mechanical tester, the stress-displacement (a) of each group is represented by the respective average level curve, and the elastic modulus (b), the elongation (c) and the maximum tensile strength (d) (n is 5for each group) P < 0.05(one-way ANOVA) are obtained by the mechanical tester (in the figure, "" represents P < 0.05).

2. Loose model testing

The method comprises the following steps: rigid polyurethane foams have small differences in material properties, uniformity, usability, etc., and are therefore used as substitutes for bone materials. Selection of grade 20 according to the American society for testing and materials (ASTM: F1839-08) Specification(0.32g/cm³) Standard rigid polyurethane foam was used as a standard test piece for bone model replacement.

Sample preparation: the product of example 5.

Testing a partial loosening model: a drill bit with the diameter of 1.0mm drills a test piece (Shanghai super group rubber and plastic Co., Ltd., China), a self-tapping screw (Guangzhou Huachuang medical treatment, China) with the diameter of 1.5mm is screwed in, and the axial pull-out force of a blank group of screws is measured by axially pulling out the drill bit by a mechanical tester; screwing out the screw after screwing in the screw, screwing in the screw along the original screw channel again, and measuring the secondary axial anti-pull-out force; meanwhile, the film-coated screw is screwed in again, and the axial pullout resistance force is detected.

Testing a complete loosening model: drilling by a drill bit with the diameter of 1.5mm to form a completely loosened nail channel, screwing in a self-tapping screw with the diameter of 1.5mm, screwing in a film-coated screw again, and detecting axial pull-out force; all tests were repeated 5 times.

The results are shown in fig. 10, a is the pull-out force curve of the screw in the case of initial axial pull-out force, secondary axial pull-out force and complete loosening in the in vitro standard test piece. And b is a pull-out force curve obtained by combining the condom screws of each group and screwing the combined condom screws into the original nail channel to perform pull-out force test under the condition of partial looseness. And c, under the condition of complete looseness, combining each group of condoms and the screws, screwing the condoms into the nail channel, and carrying out pull-out force test to obtain a pull-out force curve. d is the comparison of the primary axial extraction force, the secondary axial extraction force and the extraction force under the condition of complete looseness in the standard test piece. e is the comparison of the axial extraction force of each group of condoms and the screw after the condoms and the screw are combined under the condition of partial looseness. f is the comparison of the axial extraction force after the condoms and the screw are combined under the condition of complete looseness. (n ═ 5for reach group),. P < 0.05, (one-way ANOVA).

3. In vivo complete loosening model test

The membrane prepared in example 2 was selected for in vivo complete loosening model test according to the results of membrane mechanics test, cell compatibility test and in vitro anti-pull out test.

New Zealand white rabbits 9 (male, average 2-2.5 kg). 10% chloral hydrate, 3.5mL/kg abdominal cavity injection anesthesia, bilateral hip joint skin preparation, disinfection and spread, cutting the skin about 3cm at the greater trochanter of femur, layer by layer entering and exposing bone tissue, electric saw preparation intertrochanteric incomplete fracture, divided into three groups: drilling holes perpendicular to the fracture line by using an electric drill with the diameter of 1.5mm, screwing self-tapping screws with the diameter of 1.5mm (completely loose sets), and screwing the cladding material into the screws (safety kits); the loose-free set was screwed with a self-tapping metal screw having a diameter of 1.5mm after drilling with a 1.0mm diameter drill. After the incision is closed, 8 million units of penicillin are injected into the lower limbs of the patient through muscles for 3 days, so that infection is prevented. The results are shown in FIG. 11, where a is a schematic surgical diagram; b is a schematic diagram of the positions of the arrow nail path and the fracture line; c is a use schematic diagram of a conventional group of screws; d is a schematic diagram of the use of the experimental group of screws;

imaging examination: the results of CBCT examination on the first Day (Day 1) and the fourth week (Day 28) after surgery and at 4 weeks after surgery are shown in fig. 11, wherein e is a schematic view of a non-loose group (control) fracture; f is a schematic diagram after the non-loose group heals; g is a schematic diagram of a checking result of the CBCT of the non-loose group; h is a fracture schematic diagram of a safety kit (MS-CL); i is a schematic diagram after the safety sleeve is healed; j is a schematic diagram of the inspection result of the safety kit CBCT; k is a complete loosening group (NS-CL) fracture scheme; l is a schematic diagram after the complete loosening group is healed; and m is a schematic diagram of the CBCT inspection result of the complete loose group.

The above detailed description is specific to one possible embodiment of the present invention, and the embodiment is not intended to limit the scope of the present invention, and all equivalent implementations or modifications without departing from the scope of the present invention should be included in the technical scope of the present invention.

Claims (10)

1. A preparation method of a nano/micron fiber membrane comprises the following steps:

s1: dispersing graphene oxide in dichloromethane or six-fu isopropanol to prepare a solution, and dissolving polyhydroxyalkanoate and polyethylene glycol in the solution to obtain a solution A;

s2: taking an injector and an injection needle head, setting positive voltage, negative voltage, temperature, injection speed and receiving distance by using a tin foil paper roller as a receiver, preparing a film, drying and sterilizing.

2. The method for preparing a fibrous film according to claim 1, wherein in step S1, the polyhydroxyalkanoate is any one of a first-generation polyhydroxybutyrate, a second-generation hydroxybutyrate/valerate copolyester, a third-generation hydroxybutyrate hexanoate copolyester or a fourth-generation poly-3-hydroxybutyrate/4-hydroxybutyrate copolymer; the solution A contains 7% of polyhydroxyalkanoate, 5% of polyethylene glycol and 1mg/mL of graphene oxide in every 10 milliliters of dichloromethane or six-Formica isopropanol.

3. The method for preparing a fibrous membrane according to claim 1, wherein in step S2, the syringe has a size of 10 mL; the injection needle is a 23G injection needle; the positive voltage is 10kV, the negative voltage is 10kV, the temperature is 37 ℃, the injection speed is 0.3mm/min, and the receiving distance is 15-20 cm; the drying is carried out for 48 hours in a vacuum drier, so that the residual organic solvent is evaporated.

4. A preparation method of a hollow porous nano/micron fiber membrane is characterized by comprising the following steps:

(1) dispersing graphene oxide in dichloromethane or six-fu isopropanol to prepare a solution, and dissolving polyhydroxyalkanoate and polyethylene glycol in the solution to obtain a solution A;

(2) dissolving polyethylene glycol and osteogenic active peptide or natural small molecular compound in water to prepare solution B;

(3) respectively loading solution A and solution B into an injector, using a coaxial nozzle to take the solution A as a shell layer and the solution B as a core layer, using a silver paper roller as a receiver, setting positive voltage, negative voltage, temperature and injection speed, respectively, receiving distance to prepare a fiber film, placing the fiber film into an aqueous solution, performing ultrasonic oscillation to obtain a micron fiber film with a hollow porous structure, and performing vacuum drying and sterilization.

5. A preparation method of a hollow porous nano/micron fiber membrane is characterized by comprising the following steps:

(1) dispersing graphene oxide in dichloromethane or six-fu isopropanol to prepare a solution, and dissolving polyhydroxyalkanoate and polyethylene glycol in the solution to obtain a solution A;

(2) dissolving polyethylene glycol in water to obtain a solution B;

(3) respectively loading solution A and solution B into an injector, using a coaxial nozzle to take the solution A as a shell layer and the solution B as a core layer, using a high-speed orientation device as a receiver, setting positive voltage, negative voltage, temperature and injection speed respectively, receiving distance to prepare a fiber film, placing the fiber film into an aqueous solution, performing ultrasonic oscillation to obtain a nano/micron fiber film with an ordered-disordered hollow porous structure, repeatedly soaking the fiber film into a solution with osteogenic active peptide or a natural small molecular compound, and performing vacuum drying and sterilization.

6. The method for preparing a hollow porous nano/micro fiber membrane according to any one of claims 4 or 5, wherein in the step (2), the osteogenic active peptide or natural small molecule compound comprises: Arg-Gly-Asp peptide, collagen peptide mimic P-15, heparin binding peptide, bone morphogenetic protein-7 derived peptide, bone morphogenetic protein-2 derived peptide, glucagon-like peptide-1, osteogenic growth peptide, parathyroid hormone related peptide, QK peptide, Prominin-1derived peptide; any one or more of quercetin, puerarin, resveratrol, curcumin, epigallocatechin gallate and berberine.

7. The method for preparing a hollow porous nano/micro fiber membrane according to any one of claims 4 or 5, wherein in the step (3), the specification of the syringe is 5 mL; the positive voltage is 15kV, the negative voltage is 5kV, the temperature is 37 ℃, the injection speed is 0.5/0.1mm/min respectively, and the receiving distance is 15-20 cm; the drying is carried out for 48 hours in a vacuum drier, so that the residual organic solvent is evaporated.

8. A nano/micro fiber membrane produced by the method for producing a fiber membrane according to any one of claims 1 to 3 or the method for producing a nano/micro fiber membrane according to any one of claims 4 to 7, wherein the nano/micro fiber membrane has an ordered-disordered hollow porous microstructure.

9. The nano/micro fiber membrane according to claim 8, wherein the nano/micro fiber membrane is in the form of a membrane, or a hollow or solid cylinder, or a screw sleeve.

10. A functional absorbable orthopedic screw sleeve, which is prepared from the cellulose membrane or nano/micro fiber according to any one of claims 8 or 9, and the preparation method of the orthopedic screw sleeve comprises the following steps:

according to the requirements of the diameter and the length of the clinical orthopedic screw, the fiber membranes with the same thickness are made into sleeve shapes with different diameters and different lengths by using the intelligent rolling shaft and are integrated with the screw body.

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