Antibacterial, hemostatic and self-powered asymmetric hybrid fiber membrane and preparation method thereof

Abstract

The invention discloses an antibacterial, hemostatic and self-powered asymmetric hybrid fiber membrane and a preparation method thereof, the antibacterial, hemostatic and self-powered asymmetric hybrid fiber membrane is composed of three layers of fiber membranes, including: a bottom layer piezoelectric fiber membrane; -a core layer electrically conductive fibrous membrane; -a skin fibrous membrane; the fiber membranes are connected through spinning; the water contact angle of the bottom layer piezoelectric fiber membrane is 140-150 degrees; the water contact angle of the core layer conductive fiber membrane is 50-60 degrees; and the water contact angle of the surface fiber membrane is 20-30 degrees. The invention also discloses a preparation method of the composition. The preparation method of the hybrid nanofiber membrane is simple and controllable, the material cell and blood compatibility is good, the hybrid nanofiber membrane has the functions of promoting cell migration and blood coagulation, growth of wound specific bacteria can be inhibited, cell proliferation is expected to be accelerated through self-powered stimulation, and the hybrid nanofiber membrane has good application prospects in the fields of wound dressings, bionic skin and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of biomedical materials, and in particular relates to an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane and a preparation method thereof. Background Art

[0002] The skin is the largest organ in the human body and plays a vital role in maintaining internal stability and resisting external stimuli such as bacteria and viruses. Wound dressings serve as a protective barrier to prevent external bacterial invasion and help wound healing. The most commonly used wound dressings in clinical practice are cotton pads, gauze / bandages, and hydrogels. However, these traditional passive dressings are insufficient in providing a sterile environment and maintaining appropriate wound moisture, and are difficult to remove due to adhesion, which may cause further damage. Therefore, the research and development of new wound dressings has become a research hotspot in recent years.

[0003] Fiber is a kind of dressing material that has attracted much attention in recent years, mainly due to its unique structure and adjustable physical and mechanical properties. Nanofibers have a structure similar to the natural extracellular matrix (ECM), with a large surface area and high porosity, which is conducive to the circulation of essential nutrients and metabolites required for cell growth. Studies have shown that as a physical signal in the body, endogenous electric fields can stimulate cell growth and promote wound healing (Wang J, Lin JW, Chen L, et al. Endogenous Electric-Field-Coupled Electrospun Short Fiber via Collecting Wound Exudation [J]. Adv. Mater. 2022, 34, 2108325).

[0004] Chinese patent document CN 115387029 A discloses a method for preparing a stripe-structured self-powered wound dressing. The method obtains a stripe-structured self-powered fiber membrane by directional electrospinning, which can convert the mechanical force exerted on the skin into electrical stimulation and transmit it to the wound surface, thereby promoting cell growth and migration.

[0005] However, single hemostasis, electrical stimulation and other properties cannot meet the complex requirements of the wound site in practical applications for dressing functionality and biological environment. Therefore, in recent years, people hope to enrich the performance of fiber dressings through the synergistic effect of "layers".

[0006] Chinese patent document CN 109700562 A discloses a multilayer dual-oriented stent that mimics the structure and function of natural blood vessels and a preparation method thereof. The preparation method obtains a bionic blood vessel that is easy to evenly inoculate cells by adjusting the orientation and folding and curling of multilayer fibers, which is suitable for deeper and more complex wound repair.

[0007] The material disclosed in Chinese patent document CN 115998937 A is composed of super-hydrophilic and super-hydrophobic fiber layers, and has a Janus two-sided structure with both wettability gradient and structural gradient, so that it has hemostatic, antibacterial and drug directional transport effects.

[0008] Combining electrical stimulation with a multilayer structure is more in line with the structural characteristics of human skin. Therefore, a multilayer asymmetric dressing is designed, the functional components are screened and matched, and an asymmetric hybrid nanofiber membrane similar to human skin is prepared by electrospinning technology. Its antibacterial, hemostatic and self-powered cell growth stimulation properties are of great research value in the field of wound dressings. Summary of the invention

[0009] The first technical problem to be solved by the present invention is to provide an antibacterial, hemostatic, and self-powered asymmetric hybrid fiber membrane. The present invention uses electrospinning to prepare a three-layer asymmetric hybrid fiber membrane material through component screening and process exploration. The bottom fiber membrane is hydrophobic, and acts as a wound barrier to prevent environmental pollution and reduce bacterial adhesion. It can also generate electrical signals with changes in pressure to stimulate cell growth; the core fiber membrane is hydrophilic, and can act as a conductive pathway while also slowly releasing antibacterial substances; the last surface fiber membrane is water-soluble, and can quickly dissolve when it encounters wound tissue fluid, releasing chitosan to stop bleeding and fight bacteria.

[0010] The second technical problem to be solved by the present invention is to provide a method for preparing an antibacterial, hemostatic, and self-powered asymmetric hybrid fiber membrane. The cell migration rate, antibacterial rate, and coagulation effect of the material prepared by this method are significantly higher than those of the control group, and it is expected to be applied to wound dressings.

[0011] To solve the above-mentioned first technical problem, the technical solution adopted by the present invention is as follows: :

[0012] An antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane, composed of three layers of fiber membranes, including:

[0013] - bottom piezoelectric fiber membrane;

[0014] - Conductive fiber membrane in the core layer;

[0015] -Surface fiber membrane;

[0016] Each layer of fiber membrane is connected by spinning;

[0017] The water contact angle of the bottom piezoelectric fiber membrane is 140-150 degrees;

[0018] The water contact angle of the core layer conductive fiber membrane is 50-60 degrees;

[0019] The water contact angle of the surface fiber membrane is 20-30 degrees.

[0020] Preferably, the bottom piezoelectric fiber membrane is prepared by dissolving a piezoelectric polymer and then using an electrostatic spinning technique.

[0021] More preferably, the piezoelectric polymer is selected from one or more of polyvinylidene fluoride, polymethyl methacrylate, and epoxy resin.

[0022] Preferably, the core layer conductive fiber membrane is prepared by mixing a hydrophobic polymer, gelatin and an inorganic conductive nanomaterial to form a spinning solution for the core layer, and then using an electrostatic spinning technology.

[0023] More preferably, the hydrophobic polymer is selected from one or more of polycaprolactone, polyurethane, and polylactic acid-glycolic acid copolymer; the inorganic conductive nanomaterial is selected from one or more of copper nanoparticles, carbon nanotubes, silver nanowires, and gold nanoparticles.

[0024] Preferably, the surface fiber membrane is prepared by electrospinning technology using a spinning solution of a core layer formed by mixing a water-soluble polymer and chitosan.

[0025] More preferably, the water-soluble polymer is selected from one or more of polyvinyl alcohol, polyethylene oxide, and polyvinyl pyrrolidone.

[0026] To solve the above second technical problem, the technical solution adopted by the present invention is as follows :

[0027] A method for preparing an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane comprises the following steps:

[0028] 1) dissolving a piezoelectric polymer in an organic solvent to obtain a spinning solution, and then using the spinning solution through an electrostatic spinning technique to obtain a bottom piezoelectric fiber membrane;

[0029] 2) dissolving the hydrophobic polymer and gelatin in an acetic acid solution and stirring them evenly, and doping them with inorganic conductive nanomaterials to obtain a spinning solution for the core layer, and electrospinning the core layer conductive fiber membrane on the basis of the bottom fiber membrane;

[0030] 3) Dissolving water-soluble polymer and chitosan in acetic acid solution to obtain surface spinning solution, electrospinning the surface fiber membrane on the basis of the bottom layer and core layer conductive fiber membrane, and finally preparing an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane.

[0031] As a further improvement of the technical solution, in step 1), the piezoelectric polymer is selected from one or more of polyvinylidene fluoride, polymethyl methacrylate, and epoxy resin; the organic solvent is selected from one or more of N,N-dimethylformamide, acetone, dimethyl sulfoxide, and acetic acid.

[0032] Preferably, in step 1), the mass concentration of the piezoelectric polymer is 5-20%, and the dissolution temperature is 30-50°C.

[0033] Preferably, in step 1), the process parameters of the electrospinning are: voltage 15-25 kV, receiving distance 16-23 cm, spinning solution feed rate 0.001-0.02 mL / min; spinning environment conditions are temperature 32±6° C., humidity 40±10%.

[0034] As a further improvement of the technical solution, in step 2), the hydrophobic polymer is selected from one or more of polycaprolactone, polyurethane, and polylactic acid-glycolic acid copolymer.

[0035] Preferably, in step 2), the inorganic conductive nanomaterial is selected from one or more of copper nanoparticles, carbon nanotubes, silver nanowires, and gold nanoparticles.

[0036] Preferably, in step 2), the total mass fraction of the hydrophobic polymer and gelatin is 10-30%, the mass ratio of the hydrophobic polymer and gelatin is 4:1-1:4, the mass concentration of the acetic acid solution is 75-85%; and the solute of the inorganic conductive nanomaterial accounts for 1-10%.

[0037] Preferably, in step 2), the spinning process parameters based on the bottom fiber membrane are: voltage 12-22 kV, receiving distance 18-22 cm, spinning solution feed rate 0.001-0.01 mL / min; spinning environment conditions are temperature 32±6°C, humidity 48±5%.

[0038] As a further improvement of the technical solution, in step 3), the water-soluble polymer is selected from one or more of polyvinyl alcohol, polyethylene oxide, and polyvinyl pyrrolidone.

[0039] Preferably, in step 3), the total mass fraction of the water-soluble polymer and chitosan is 1-4%, the mass ratio of the water-soluble polymer to chitosan is 1:9-1:1, and the mass concentration of the acetic acid solution is 45-55%.

[0040] Preferably, in step 3), the process parameters for spinning on the basis of the bottom layer and core layer fiber membrane are: voltage 12-22 kV, receiving distance 18-22 cm, spinning solution feed rate 0.001-0.01 mL / min; spinning environment conditions are temperature 30±6°C, humidity 45±5%.

[0041] Any range described in the present invention includes the end value and any numerical value between the end values ​​and any sub-range formed by the end value or any numerical value between the end values.

[0042] Unless otherwise specified, all raw materials in the present invention can be purchased from the market, and the equipment used in the present invention can adopt conventional equipment in the relevant field or refer to the existing technology in the relevant field.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. The present invention is designed with a three-layer asymmetric structure: the hydrophobic layer serves as a protective barrier for the wound surface, and after self-generating electricity, it is transmitted to cells through the conductive layer to stimulate growth; the water-soluble layer quickly dissolves when encountering a moist wound, releasing chitosan to stop bleeding and fight bacteria.

[0045] 2. Natural organic matter and metal inorganic matter work synergistically as functional substances, not only having good antibacterial and hemostatic effects, but also reducing cell resistance;

[0046] 3. The electrospinning process is simple and controllable, and the prepared fiber material is structurally similar to the extracellular matrix, which helps cell migration and growth. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0048] Figure 1 This is a scanning electron microscope image of the product of Example 1 of the present invention; wherein a is the planar structure of the surface layer, b is the planar structure of the core layer, and c is the planar structure of the bottom layer;

[0049] Figure 2 This is a transmission electron microscope image of the core fiber of the product of Example 1 of the present invention;

[0050] Figure 3 This is a cross-sectional scanning electron microscope image of the product of Example 1 of the present invention;

[0051] Figure 4 The water contact angle photos of the product of Example 1 of the present invention: a is a photo of the water contact angle of the surface layer, b is a photo of the water contact angle of the core layer, and c is a photo of the water contact angle of the bottom layer;

[0052] Figure 5 This is a histogram of the antibacterial experiment of the product of Example 1 of the present invention;

[0053] Figure 6 a Cell compatibility bar graph of the product of Example 1 of the present invention; Figure 6 b is a histogram of cell scratches in Example 1 of the present invention;

[0054] Figure 7 This is a histogram of the coagulation performance of the product of Example 1 of the present invention;

[0055] Figure 8 This is an open circuit voltage test diagram of the product of Example 1 of the present invention;

[0056] Fig. 9 This is a scanning electron microscope image of the core layer of the product of Example 2 of the present invention;

[0057] Fig.10 This is a cross-sectional scanning electron microscope image of the product of Example 2 of the present invention;

[0058] Fig.11 This is a cross-sectional scanning electron microscope image of the product of Comparative Example 1 of the present invention;

[0059] Fig.12 This is a scanning electron microscope image of the surface layer of the product of Comparative Example 2 of the present invention. DETAILED DESCRIPTION

[0060] In order to explain the present invention more clearly, the present invention is further described below in conjunction with embodiments. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0061] See also Figure 3 As shown, as one aspect of the present invention, the present invention provides an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane, which is composed of three layers of fiber membranes, including:

[0062] - Bottom piezoelectric fiber membrane 1, which converts different forces into electrical signals through piezoelectric effect;

[0063] - The core layer conductive fiber membrane 2 is used to transmit the electrical signal generated by the piezoelectric fiber membrane to the surface layer and even the skin through the conductive path formed by the nano silver wires, and continuously resist bacteria under the slow release effect;

[0064] -Surface fiber membrane 3, its function is to quickly kill bacteria and stop bleeding;

[0065] Each layer of fiber membrane is connected by spinning;

[0066] The water contact angle of the bottom piezoelectric fiber membrane is 140-150 degrees;

[0067] The water contact angle of the core layer conductive fiber membrane is 50-60 degrees;

[0068] The water contact angle of the surface fiber membrane is 20-30 degrees.

[0069] In some embodiments of the present invention, the bottom piezoelectric fiber membrane is prepared by dissolving a piezoelectric polymer and then using an electrostatic spinning technique.

[0070] In some embodiments of the present invention, the piezoelectric polymer is selected from one or more of polyvinylidene fluoride, polymethyl methacrylate, and epoxy resin.

[0071] In certain embodiments of the present invention, the core conductive fiber membrane is prepared by electrospinning technology using a spinning solution of the core layer formed by mixing a hydrophobic polymer, gelatin and an inorganic conductive nanomaterial.

[0072] In certain embodiments of the present invention, the hydrophobic polymer is selected from one or more of polycaprolactone, polyurethane, and polylactic acid-glycolic acid copolymer; the inorganic conductive nanomaterial is selected from one or more of copper nanoparticles, carbon nanotubes, silver nanowires, and gold nanoparticles.

[0073] In certain embodiments of the present invention, the surface fiber membrane is prepared by electrospinning technology using a spinning solution of a core layer formed by mixing a water-soluble polymer and chitosan.

[0074] In certain embodiments of the present invention, the water-soluble polymer is selected from one or more of polyvinyl alcohol, polyethylene oxide, and polyvinyl pyrrolidone.

[0075] As one aspect of the present invention, the present invention provides an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane and a preparation method thereof, comprising the following steps:

[0076] 1) dissolving a piezoelectric polymer in an organic solvent to obtain a spinning solution, and then using the spinning solution through an electrostatic spinning technique to obtain a bottom piezoelectric fiber membrane;

[0077] 2) dissolving the hydrophobic polymer and gelatin in an acetic acid solution and stirring them evenly, and doping them with inorganic conductive nanomaterials to obtain a spinning solution for the core layer, and electrospinning the core layer conductive fiber membrane on the basis of the bottom fiber membrane;

[0078] 3) Dissolving water-soluble polymer and chitosan in acetic acid solution to obtain surface spinning solution, electrospinning the surface fiber membrane on the basis of the bottom layer and core layer conductive fiber membrane, and finally preparing an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane.

[0079] In certain embodiments of the present invention, in step 1), the piezoelectric polymer is selected from one or more of polyvinylidene fluoride, polymethyl methacrylate, and epoxy resin; the organic solvent is selected from one or more of N,N-dimethylformamide, acetone, dimethyl sulfoxide, and acetic acid.

[0080] In some embodiments of the present invention, in step 1), the mass concentration of the piezoelectric polymer is 5-20%, and the dissolution temperature is 30-50°C.

[0081] In certain embodiments of the present invention, in step 1), the process parameters of the electrospinning are: voltage 15-25 kV, receiving distance 16-23 cm, spinning solution feed rate 0.001-0.02 mL / min; spinning environment conditions are temperature 32±6°C, humidity 40±10%.

[0082] In certain embodiments of the present invention, in step 2), the hydrophobic polymer is selected from one or more of polycaprolactone, polyurethane, and polylactic acid-co-glycolic acid.

[0083] In certain embodiments of the present invention, in step 2), the inorganic conductive nanomaterial is selected from one or more of copper nanoparticles, carbon nanotubes, silver nanowires, and gold nanoparticles.

[0084] In certain embodiments of the present invention, in step 2), the total mass fraction of the hydrophobic polymer and gelatin is 10-30%, the mass ratio of the hydrophobic polymer and gelatin is 4:1-1:4, the mass concentration of the acetic acid solution is 75-85%; and the solute of the inorganic conductive nanomaterial accounts for 1-10%.

[0085] In certain embodiments of the present invention, in step 2), the process parameters of spinning based on the bottom fiber membrane are: voltage 12-22 kV, receiving distance 18-22 cm, spinning solution feed rate 0.001-0.01 mL / min; the spinning environment conditions are temperature 32±6°C and humidity 48±5%.

[0086] In certain embodiments of the present invention, in step 3), the water-soluble polymer is selected from one or more of polyvinyl alcohol, polyethylene oxide, and polyvinyl pyrrolidone.

[0087] In certain embodiments of the present invention, in step 3), the total mass fraction of the water-soluble polymer and chitosan is 1-4%, the mass ratio of the water-soluble polymer to chitosan is 1:9-1:1, and the mass concentration of the acetic acid solution is 45-55%.

[0088] In certain embodiments of the present invention, in step 3), the process parameters for spinning on the basis of the bottom layer and core layer fiber membranes are: voltage 12-22 kV, receiving distance 18-22 cm, spinning solution feed rate 0.001-0.01 mL / min; the spinning environment conditions are temperature 30±6°C and humidity 45±5%.

[0089] Example 1

[0090] An antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane and a preparation method thereof, comprising the following steps:

[0091] 1) Weigh 0.89 g polyvinylidene fluoride (M w 400000) was added into 8 g of N,N-dimethylformamide, and stirred and dissolved at 40°C for 4 hours to prepare a PVDF solution with a mass fraction of 10%;

[0092] 2) Spinning conditions: process parameters: voltage 20 kV, receiving distance 21 cm, feed rate 0.01 mL / min; environmental conditions are temperature 32° C., humidity 45%, and spinning for 6.5 h to obtain the bottom piezoelectric nanofiber film.

[0093] 3) Weigh 1.6 g of polycaprolactone and 0.4 g of gelatin respectively, place them in 4.8 g of glacial acetic acid, and then add 1.2 g of 31.5 mg / mL nanosilver wire aqueous dispersion to finally obtain a mixed solution with a total mass fraction of polycaprolactone and gelatin of 25% and a mass ratio of 4:1. After stirring overnight, ultrasonicate for 15 min to obtain the spinning solution of the core fiber membrane.

[0094] 4) Spinning conditions: process parameters: voltage 18 kV, receiving distance 21 cm, feed rate 0.008 mL / min; environmental conditions are temperature 30°C, humidity 45%, with the bottom piezoelectric fiber membrane as the receiver, and the core layer conductive fiber film can be obtained by spinning for 8 hours.

[0095] 6) Weigh 37.11 mg of polyethylene oxide and 148.45 mg of chitosan respectively, place in 6 g of 50% acetic acid solution, stir overnight, and obtain a surface spinning solution with a total mass fraction of polyethylene oxide and chitosan of 3% and a mass ratio of 1:4.

[0096] 7) Spinning conditions: process parameters: voltage 18 kV, receiving distance 21 cm, feed rate 0.008 mL / min; spinning environment conditions are temperature 32 ° C, humidity 48%, and spinning is continued for 8 hours on the basis of the first two layers of fiber membrane to obtain a surface polyethylene oxide / chitosan fiber membrane. The overall product is an asymmetric three-layer hybrid nanofiber membrane.

[0097] After testing, the present embodiment obtains an asymmetric three-layer hybrid nanofiber membrane, and the water contact angle of each layer of fibers is as follows: Figure 4 As shown, the hydrophilicity and hydrophobicity are different.

[0098] like Figure 5 As shown, the inhibition rate of both broad-spectrum bacteria and wound-specific bacteria Pseudomonas aeruginosa reached more than 99%;

[0099] like Figure 6 As shown in a, the cell survival rate is greater than 90%, which promotes good cell compatibility; Figure 6 As shown in b, the asymmetric three-layer hybrid nanofiber membrane can promote cell migration to a greater extent through the synergistic effect of each layer of materials;

[0100] like Figure 7 As shown, the asymmetric three-layer hybrid fiber exhibited good coagulation effect;

[0101] like Figure 8As shown, by repeatedly applying the same pressure to the material, the material produces a stable voltage signal that can stimulate cell growth.

[0102] Example 2

[0103] An antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane and a preparation method thereof, comprising the following steps:

[0104] 1) Weigh 0.89 g polyvinylidene fluoride (M w 400000) was added into 8 g of N,N-dimethylformamide, and stirred and dissolved at 40°C for 4 hours to prepare a PVDF solution with a mass fraction of 10%;

[0105] 2) Spinning conditions: process parameters: voltage 20 kV, receiving distance 21 cm, feed rate 0.01 mL / min; environmental conditions are temperature 32° C., humidity 45%, and spinning for 6.5 h to obtain the bottom piezoelectric nanofiber film.

[0106] 3) Weigh 1.6 g of polycaprolactone and 0.4 g of gelatin respectively, place them in 4.8 g of glacial acetic acid, and then add 1.2 g of 67.5 mg / mL nanosilver wire aqueous dispersion to finally obtain a mixed solution with a total mass fraction of polycaprolactone and gelatin of 25% and a mass ratio of 4:1. After stirring overnight, ultrasonicate for 15 min to obtain the spinning solution of the core fiber membrane.

[0107] 4) Spinning conditions: process parameters: voltage 18 kV, receiving distance 21 cm, feed rate 0.008 mL / min; environmental conditions are temperature 30°C, humidity 45%, with the bottom piezoelectric fiber membrane as the receiver, and the core layer conductive fiber film can be obtained by spinning for 8 hours.

[0108] 6) Weigh 37.11 mg of polyethylene oxide and 148.45 mg of chitosan respectively, place in 6 g of 50% acetic acid solution, stir overnight, and obtain a surface spinning solution with a total mass fraction of polyethylene oxide and chitosan of 3% and a mass ratio of 1:4.

[0109] 7) Spinning conditions: process parameters: voltage 18 kV, receiving distance 21 cm, feed rate 0.008 mL / min; spinning environment conditions are temperature 32 ° C, humidity 48%, and spinning is continued for 8 hours on the basis of the first two layers of fiber membrane to obtain a surface polyethylene oxide / chitosan fiber membrane. The overall product is an asymmetric three-layer hybrid nanofiber membrane.

[0110] Fig. 9 The SEM image of the conductive core layer is shown. Figure 1The fibers are obviously thinner than those in b. The reason is that due to the increase in the content of silver nanowires, the conductivity of the fibers is enhanced. Under the same process conditions, they are subjected to stronger electric field forces, the fibers are pulled thinner, and the inhomogeneity of the viscous system caused by the nanomaterials causes some spindle-shaped fibers to appear.

[0111] Comparative Example 1

[0112] Example 1 was repeated, except that the mass ratio of polycaprolactone to gelatin in the core layer spinning solution was changed to 1:4. Step 3) was changed to: 0.4 g of polycaprolactone and 1.6 g of gelatin were weighed separately, placed in 4.8 g of glacial acetic acid, and then 1.2 g of a 31.5 mg / mL aqueous dispersion of nanosilver wires was added dropwise, and finally a mixed solution with a total mass fraction of polycaprolactone and gelatin of 25% and a mass ratio of 4:1 was obtained. Other conditions and specific operating steps were completely consistent with Example 1.

[0113] Fig.11 The scanning electron microscope photo of the product obtained in this example shows that due to the significant increase in the proportion of hydrophilic gelatin, the cross section of the product is obviously sticky, and as the hydrophilicity of the core layer increases, the release rate in a humid environment increases, and more silver nanowires are released, which may cause the conductive layer to be disconnected, and the product cannot transmit electrical stimulation to the surface layer.

[0114] Comparative Example 2

[0115] Example 1 was repeated, except that the mass ratio of polyethylene oxide to chitosan in the surface spinning solution was changed to 1:9. Other conditions and specific operating steps were completely consistent with those in Example 1.

[0116] The results showed that due to the high content of chitosan on the surface repelling at the needle tip, liquid dripping occurred at the needle tip during the spinning process and a fiber structure could not be formed.

[0117] Obviously, the above embodiments and comparative examples of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the embodiments here. Any obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. An antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane, consisting of three layers of fiber membranes, including: - bottom piezoelectric fiber membrane; -Core conductive fiber membrane; -Surface fiber membrane; Each layer of fiber membrane is connected by spinning; The water contact angle of the bottom piezoelectric fiber membrane is 140-150 degrees; The water contact angle of the core layer conductive fiber membrane is 50-60 degrees; The water contact angle of the surface fiber membrane is 20-30 degrees.

2. The antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane according to claim 1, characterized in that: The bottom piezoelectric fiber membrane is prepared by dissolving a piezoelectric polymer and then using an electrostatic spinning technology.

3. The antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane according to claim 2, characterized in that: The piezoelectric polymer is selected from one or more of polyvinylidene fluoride, polymethyl methacrylate, and epoxy resin.

4. The antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane according to claim 1, characterized in that: The core layer conductive fiber membrane is prepared by using a spinning solution of the core layer formed by mixing a hydrophobic polymer, gelatin and an inorganic conductive nano material and then using an electrostatic spinning technology.

5. The antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane according to claim 4, characterized in that: The hydrophobic polymer is selected from one or more of polycaprolactone, polyurethane, and polylactic acid-glycolic acid copolymer; the inorganic conductive nanomaterial is selected from one or more of copper nanoparticles, carbon nanotubes, silver nanowires, and gold nanoparticles.

6. The antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane according to claim 1, characterized in that: The surface fiber membrane is made of a spinning solution of a core layer formed by mixing a water-soluble polymer and chitosan, and then is prepared by electrostatic spinning technology.

7. The antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane according to claim 6, characterized in that: The water-soluble polymer is selected from one or more of polyvinyl alcohol, polyethylene oxide, and polyvinyl pyrrolidone.

8. The method for preparing an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane according to any one of claims 1 to 7, characterized in that: The steps include: 1) dissolving a piezoelectric polymer in an organic solvent to obtain a spinning solution, and then using the spinning solution through an electrostatic spinning technique to obtain a bottom piezoelectric fiber membrane; 2) dissolving the hydrophobic polymer and gelatin in an acetic acid solution and stirring them evenly, and doping them with inorganic conductive nanomaterials to obtain a spinning solution for the core layer, and electrospinning the core layer conductive fiber membrane on the basis of the bottom fiber membrane; 3) Dissolving water-soluble polymer and chitosan in acetic acid solution to obtain surface spinning solution, electrospinning the surface fiber membrane on the basis of the bottom layer and core layer conductive fiber membrane, and finally preparing an antibacterial, hemostatic, self-powered asymmetric hybrid fiber membrane.

9. The preparation method according to claim 8, characterized in that: In step 1), the piezoelectric polymer is selected from one or more of polyvinylidene fluoride, polymethyl methacrylate, and epoxy resin; the organic solvent is selected from one or more of N,N-dimethylformamide, acetone, dimethyl sulfoxide, and acetic acid; Preferably, in step 1), the mass concentration of the piezoelectric polymer is 5-20%, and the dissolution temperature is 30-50° C.; Preferably, in step 1), the process parameters of the electrospinning are: voltage 15-25 kV, receiving distance 16-23 cm, spinning solution feed rate 0.001-0.02 mL / min; spinning environment conditions are temperature 32±6° C., humidity 40±10%.

10. The preparation method according to claim 8, characterized in that: In step 2), the hydrophobic polymer is selected from one or more of polycaprolactone, polyurethane, and polylactic acid-co-glycolic acid; Preferably, in step 2), the inorganic conductive nanomaterial is selected from one or more of copper nanoparticles, carbon nanotubes, silver nanowires, and gold nanoparticles; Preferably, in step 2), the total mass fraction of the hydrophobic polymer and gelatin is 10-30%, the mass ratio of the hydrophobic polymer to the gelatin is 4:1-1:4, the mass concentration of the acetic acid solution is 75-85%; the solute of the inorganic conductive nanomaterial accounts for 1-10%; Preferably, in step 2), the spinning process parameters on the basis of the bottom fiber membrane are: voltage 12-22 kV, receiving distance 18-22 cm, spinning solution feed rate 0.001-0.01 mL / min; spinning environment conditions are temperature 32±6°C, humidity 48±5%; Preferably, in step 3), the water-soluble polymer is selected from one or more of polyvinyl alcohol, polyethylene oxide, and polyvinyl pyrrolidone; Preferably, in step 3), the total mass fraction of the water-soluble polymer and chitosan is 1-4%, the mass ratio of the water-soluble polymer to chitosan is 1:9-1:1, and the mass concentration of the acetic acid solution is 45-55%; Preferably, in step 3), the process parameters for spinning on the basis of the bottom layer and core layer fiber membrane are: voltage 12-22 kV, receiving distance 18-22 cm, spinning solution feed rate 0.001-0.01 mL / min; spinning environment conditions are temperature 30±6°C, humidity 45±5%.

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