Spinning solution, electrospun membrane and preparation method thereof

Abstract

The application relates to a spinning solution, an electrostatic spinning film and a preparation method thereof, and belongs to the technical field of electrostatic spinning. The spinning solution comprises the following components in parts by weight: 5-20 parts by weight of in-vivo-degradable amorphous polymer, 0.5-3 parts by weight of water-soluble polymer, 0.01-1.5 parts by weight of antibacterial agent and solvent. The weight-average molecular weight of the in-vivo-degradable amorphous polymer is not less than 80,000. After the spinning solution forms the electrostatic spinning film, the antibacterial agent can be well used, the growth of bacteria can be effectively inhibited, and therefore the antibacterial effect of the electrostatic spinning film is better.

Description

Technical Field

[0001] This application relates to the field of electrospinning technology, and in particular to a spinning solution, an electrospinning film, and a method for preparing the same. Background Technology

[0002] In existing technologies, electrospun membranes can be adhered to damaged tissue to promote tissue repair. Since tissue damage is often accompanied by inflammation, antibacterial components are typically added to the electrospun membrane to inhibit bacterial growth.

[0003] However, in practical use, the inventors found that the antibacterial agents often fail to work effectively, resulting in increased bacterial growth at the site of tissue damage and slower healing. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present application aims to provide a spinning solution, an electrospinning membrane, and a method for preparing the same. After the spinning solution forms an electrospinning membrane, it effectively inhibits bacterial growth, thereby improving the antibacterial effect of the electrospinning membrane.

[0005] In a first aspect, embodiments of this application provide a spinning solution, comprising, by weight: 5-20 parts by weight of a biodegradable amorphous polymer, 0.5-3 parts by weight of a water-soluble polymer, 0.01-1.5 parts by weight of an antibacterial agent and a solvent. The biodegradable amorphous polymer has a weight-average molecular weight of not less than 80,000.

[0006] In the above technical solution, biodegradable amorphous polymers possess excellent biocompatibility and degradability. Therefore, the spinning solution contains a high content of biodegradable amorphous polymers with higher molecular weights, serving as the main component of the spinning solution to ensure better biocompatibility and degradability of the resulting electrospun membrane. However, electrospun membranes with this main component are prone to shrinkage after covering or filling damaged tissue, resulting in ineffective antibacterial agents. The inventors investigated the cause of this shrinkage and discovered that the presence of exudate in the damaged tissue environment causes the biodegradable amorphous polymers to absorb water and swell, leading to a slippage of the amorphous molecular chains. This causes the glass transition temperature of the material to drop to or below body temperature (36℃~38℃), resulting in shrinkage. In this application, a small amount of water-soluble polymer is added to the spinning solution. The exudate from the damaged tissue will preferentially combine with the water-soluble polymer and undergo swelling. This makes it difficult for the exudate from the damaged tissue to combine with the biodegradable amorphous polymer and change its glass transition temperature. This can limit the shrinkage of the spun membrane to a certain extent, so that the antibacterial agent can play a good role, effectively inhibiting bacterial growth and making the antibacterial effect of the electrospun membrane better.

[0007] In some embodiments, the water-soluble polymer includes a synthetic water-soluble polymer with a weight-average molecular weight of not less than 50,000, and the antibacterial agent is a low-molecular-weight antibacterial agent with a weight-average molecular weight of not more than 10,000.

[0008] In the aforementioned technical solutions, the antibacterial agent has a low molecular weight and does not form a fibrous structure on the electrospun membrane. It typically exists on the electrospun membrane in the form of particles or short threads. After the electrospun membrane shrinks, some of the antibacterial agent is easily trapped inside the shrunken membrane, resulting in poor performance of the antibacterial agent. However, the addition of a small amount of a synthetic water-soluble polymer with a higher molecular weight can improve this problem. This polymer can form fibrous strands together with biodegradable amorphous polymers. It can preferentially bind to exudate at the site of tissue damage and also stabilize the fibrous structure, thereby making the electrospun membrane less prone to shrinkage and improving the performance of the antibacterial agent.

[0009] In some embodiments, the spinning solution further includes 0.1 to 3 parts by weight of a bioactive substance.

[0010] In the above technical solution, the addition of bioactive substances can be combined with low-molecular-weight antibacterial agents to enable the electrospun membrane to promote cell proliferation, effectively inhibit bacterial growth, and facilitate tissue repair and regeneration.

[0011] In some embodiments, the weight-average molecular weight of in vivo degradable amorphous polymers is 80,000 to 300,000; the weight-average molecular weight of bioactive substances is greater than 10,000; the weight-average molecular weight of synthetic water-soluble polymers is 50,000 to 500,000; and the weight-average molecular weight of low molecular weight antibacterial agents is 1,000 to 10,000.

[0012] In the above technical solution, the weight average molecular weight of both the bioactive substance and the synthetic water-soluble polymer is 50,000 to 500,000. The high molecular weight of both the bioactive substance and the synthetic water-soluble polymer allows them to form filaments simultaneously with the biodegradable amorphous polymer during the electrospinning process, which can improve the performance of the bioactive substance. When combined with low-molecular-weight antibacterial agents, the electrospun membrane can have better antibacterial and proliferative effects, which is beneficial for tissue repair and regeneration.

[0013] In some embodiments, the weight-average molecular weight of in vivo degradable amorphous polymers is 80,000 to 300,000; the weight-average molecular weight of bioactive substances is 1,000 to 10,000; the weight-average molecular weight of synthetic water-soluble polymers is 50,000 to 500,000; and the weight-average molecular weight of low molecular weight antibacterial agents is 1,000 to 10,000.

[0014] In the above technical solution, the combination of high-molecular-weight biodegradable amorphous polymers and synthetic water-soluble polymers can give the electrospun membrane good biocompatibility, biodegradability, and anti-shrinkage properties. Furthermore, combining it with small amounts of low-molecular-weight bioactive substances and antibacterial agents allows both to achieve optimal performance.

[0015] In some embodiments, the spinning solution comprises: 5 to 20 parts by weight of a biodegradable amorphous polymer, 0.1 to 2 parts by weight of a bioactive substance, 0.5 to 2 parts by weight of a synthetic water-soluble polymer, and 0.1 to 1.5 parts by weight of an antibacterial agent.

[0016] In the above technical solution, adding a small amount of synthetic water-soluble polymer can effectively suppress the shrinkage of the electrospun membrane. Thus, by adding a small amount of bioactive substances and antibacterial agents, the functionality of both can be well utilized, thereby improving the overall performance of the electrospun membrane.

[0017] In some embodiments, the weight part X of the in vivo degradable amorphous polymer is greater than the sum of the weight parts Y of the bioactive substance, the synthetic water-soluble polymer, and the antibacterial agent.

[0018] In the above technical solution, the biodegradable amorphous polymer is the main component of the spinning solution, which can improve the biocompatibility and degradation effect of the electrospinning membrane. Furthermore, when combined with the synthetic water-soluble polymer, even if the amount of antibacterial agent and bioactive substance added is very small, the performance of both can be well utilized.

[0019] In some embodiments, X > 5 × Y.

[0020] In some embodiments, the in vivo degradable amorphous polymers include at least one of racemic polylactic acid and polylactic-glycolic acid copolymer.

[0021] In the above technical solution, the selected materials have good in vivo biodegradability and biocompatibility, so as to serve as the main component of the electrospun membrane.

[0022] In some embodiments, the bioactive substance includes at least one of collagen, growth factor, silk fibroin, corn protein, gelatin, and hyaluronic acid.

[0023] In the above technical solution, the selection of the above-mentioned bioactive substances has a good effect on promoting cell proliferation, so that the electrospun membrane can promote tissue repair and regeneration.

[0024] In some embodiments, the synthesized water-soluble polymer includes at least one of polyethylene oxide, polyethylene glycol, polyvinyl alcohol, polyacrylamide, and polyvinylpyrrolidone.

[0025] In the above technical solution, adding a small amount of the above-mentioned components can effectively improve the anti-shrinkage effect of the electrospun film, so that the antibacterial agent and active substances can perform better.

[0026] In some embodiments, the antimicrobial agent includes inorganic antimicrobial agents and / or organic antimicrobial agents.

[0027] In the above technical solutions, the molecular weight of the antibacterial agent is relatively small. If the electrospinning film shrinks, the effect of the antibacterial agent will not be easily exerted. Therefore, the antibacterial agent is combined with other components in the spinning solution to enable the antibacterial agent to exert its effect better.

[0028] In some embodiments, the organic antimicrobial agent includes at least one of guanidine antimicrobial agents, β-lactam antimicrobial agents, and quaternary ammonium salt antimicrobial agents.

[0029] In some embodiments, guanidine antimicrobial agents include at least one of polyhexamethylene guanidine, polyhexamethylene biguanide, polyaminopropyl biguanide, and dodecyl guanidine acetate.

[0030] In some embodiments, β-lactam antimicrobial agents include penicillin and / or cephalosporins.

[0031] In some embodiments, quaternary ammonium salt antibacterial agents include at least one of alkyltrimethylammonium chloride, alkyldimethylbenzylammonium chloride, and tetradecyl-2-methylpyridineammonium bromide.

[0032] In some embodiments, the solute mass ratio of the spinning solution is 5% to 30%.

[0033] In the above technical solution, the mass ratio of solute in the spinning solution is within the above range, which makes it easy to stabilize into fibers by electrospinning equipment. Furthermore, the fibrous structure of the electrospinning membrane can simulate the extracellular matrix, thus facilitating tissue repair and regeneration when it is covered or filled at the site of tissue damage.

[0034] Secondly, this application provides an electrospinning method, in which the spinning solution provided in any of the first aspects is sprayed onto a receiving device under the conditions of a spinning voltage of 5kV to 30kV and a spinning solution flow rate of 0.2ml / h to 1ml / h.

[0035] In the above technical solution, the electrospun membrane obtained under the above spinning conditions is suitable for covering or filling damaged tissues, which is beneficial to promoting cell proliferation and can also effectively inhibit bacterial growth, thereby accelerating tissue repair and regeneration.

[0036] In some embodiments, the temperature of the spinning environment is 20°C to 35°C, and the humidity is 35% to 60%.

[0037] In the above technical solution, spinning under this temperature and humidity environment can make spinning more stable and is conducive to the formation of a stable electrospun film.

[0038] In some embodiments, the receiving device is a receiving roller, and the rotational speed of the receiving roller is 300 r / min to 3000 r / min.

[0039] The above technical solution can make the distribution of nanofibers in the electrospinning membrane more uniform, which is beneficial to the evaporation of solvent in the spinning solution during the spinning process.

[0040] Thirdly, this application provides an electrospun film obtained by the electrospun method provided in any of the second aspects.

[0041] In the above technical solution, the electrospun membrane prepared by this method is suitable for covering or filling damaged tissues, which is beneficial to promoting cell proliferation and can also effectively inhibit bacterial growth, thereby accelerating tissue repair and regeneration. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 The diagram shows the antibacterial properties of the electrospun membranes provided in some embodiments and comparative examples of this application. Detailed Implementation

[0044] Electrospun membranes are fibrous films manufactured using electrospinning, possessing high strength and flexibility. To impart specific functions to electrospun membranes, substances with corresponding functions are typically added to the electrospinning solution during electrospinning. For example, to impart antibacterial effects to electrospun membranes, antibacterial agents are usually added to the electrospinning solution to inhibit bacterial growth.

[0045] Antibacterial electrospun membranes are typically applied to or filled with damaged tissue (e.g., skin, subcutaneous fascia, muscle, tendon sheath, ligament, peripheral nerves and blood vessels). Therefore, if the electrospun membrane has good in vivo absorption or metabolism properties and good biocompatibility, its performance can be improved. Thus, biodegradable amorphous polymers (e.g., polylactic acid-glycolic acid copolymer) can be used as the base material for the electrospun membrane. After the base material forms the electrospun membrane, it usually shrinks after covering or filling the damaged tissue for a period of time, resulting in the antibacterial agent in the electrospun membrane not being able to perform well.

[0046] The inventors, through research on the causes of shrinkage in electrospun membranes, discovered that under dry conditions, the glass transition temperature of polylactic acid-glycolic acid copolymer (PLA-GAC) is approximately 48°C (its deformation temperature is higher than both ambient and human body temperature). However, due to the presence of exudate at the site of tissue damage, the PLA-GAC matrix component in the electrospun membrane easily absorbs water and swells, causing amorphous molecular chains to slip. After absorbing water for a period of time, this lowers the glass transition temperature of the material, bringing it to the same level as or below human body temperature (36°C–38°C), thus causing shrinkage. Therefore, based on the problem of shrinkage easily occurring when biodegradable amorphous polymers cover or fill damaged tissue sites for a period of time, improvements were made to the spinning solution, the electrospinning method, and the electrospun membrane, as detailed below.

[0047] spinning solution

[0048] This application provides a spinning solution, comprising, by weight: 5-20 parts by weight of a biodegradable amorphous polymer, 0.5-3 parts by weight of a water-soluble polymer, 0.01-1.5 parts by weight of an antibacterial agent and a solvent. The biodegradable amorphous polymer has a weight-average molecular weight of not less than 80,000.

[0049] Biodegradability includes in vitro biodegradability (e.g., soil degradation, environmental degradation) and in vivo biodegradability (absorbable or metabolizable in vivo). In vitro biodegradability does not necessarily imply good biocompatibility (meaning it is safe and non-toxic to humans, with low or no rejection response), while in vivo biodegradability usually has good biocompatibility, allowing the formed electrospun membrane to cover or fill damaged tissue. In vivo degradable amorphous polymers are polymers that are both high-molecular-weight polymers that can be absorbed or metabolized in vivo and amorphous polymers. They exhibit swelling in media such as water or ethanol, causing relative sliding of the molecular chains. Therefore, after prolonged coverage or filling of damaged tissue, the electrospun membrane formed from an in vivo degradable amorphous polymer will shrink. This application is an improvement based on the shrinkage characteristics of this polymer. The weight-average molecular weight of the in vivo degradable amorphous polymer is not less than 80,000. In the electrospun membrane formed by this spinning solution, the component forming the fibers is mainly the in vivo degradable amorphous polymer, which constitutes the main body of the electrospun membrane.

[0050] Water-soluble polymers refer to: biological water-soluble polymers and / or synthetic water-soluble polymers. Biological water-soluble polymers are those whose raw material source is biological (e.g., bioactive substances), while synthetic water-soluble polymers are those whose raw material source is artificially synthesized and does not contain the substance in natural biological materials. The water-soluble polymers in this application can be of biological or artificial origin, and can be added simultaneously; this application does not impose any limitations.

[0051] In such spinning solutions, biodegradable amorphous polymers possess excellent biocompatibility and degradability. Therefore, the spinning solution contains a high content of biodegradable amorphous polymers with higher molecular weights, serving as the main component to ensure better biocompatibility and degradability of the resulting electrospun membrane. However, electrospun membranes with this main component are prone to shrinkage when applied to damaged tissue, hindering the effectiveness of antibacterial agents. The inventors investigated the cause of this shrinkage and discovered that the presence of exudate in the damaged tissue environment causes the biodegradable amorphous polymers to absorb water and swell, leading to a slippage of the amorphous molecular chains. This causes the glass transition temperature of the material to drop to or below body temperature (36℃~38℃), resulting in shrinkage. In this application, a small amount of water-soluble polymer is added to the spinning solution. The exudate from the damaged tissue will preferentially combine with the water-soluble polymer and undergo swelling. This makes it difficult for the exudate from the damaged tissue to combine with the biodegradable amorphous polymer and change its glass transition temperature. This can limit the shrinkage of the electrospun membrane to a certain extent, so that the antibacterial agent can play a good role, effectively inhibiting bacterial growth and making the antibacterial effect of the electrospun membrane better.

[0052] In some embodiments, the water-soluble polymer includes a synthetic water-soluble polymer with a weight-average molecular weight of not less than 50,000, and the antibacterial agent is a low-molecular-weight antibacterial agent with a weight-average molecular weight of not more than 10,000. The synthetic water-soluble polymer has a higher molecular weight, allowing it to co-form filaments with biodegradable amorphous polymers, while the antibacterial agent has a lower molecular weight and is generally not capable of forming filaments, typically existing as granules or short threads.

[0053] Because antibacterial agents have low molecular weights, they do not form fibrous structures on electrospun membranes. They typically exist as granules or short threads. After the electrospun membrane shrinks, some of the antibacterial agent is easily trapped inside the shrunken membrane, resulting in poor performance. However, the addition of a small amount of high-molecular-weight synthetic water-soluble polymer can improve this problem. This polymer can form fibrous strands together with biodegradable amorphous polymers. These strands can preferentially bind to exudate at the site of tissue damage and also stabilize the fibrous structure, making the electrospun membrane less prone to shrinkage and improving the performance of the antibacterial agent.

[0054] In some embodiments, the spinning solution further includes 0.1 to 3 parts by weight of a bioactive substance. The addition of the bioactive substance can be combined with a low-molecular-weight antibacterial agent to enable the electrospun membrane to promote cell proliferation, effectively inhibit bacterial growth, and facilitate tissue repair and regeneration.

[0055] The bioactive substance may be water-soluble or water-insoluble. In some embodiments, the bioactive substance is a water-soluble bioactive substance, and the spinning solution comprises 5 to 20 parts by weight of a biodegradable amorphous polymer, 0.5 to 3 parts by weight of the water-soluble bioactive substance, 0.01 to 1.5 parts by weight of an antibacterial agent and a solvent. The biodegradable amorphous polymer has a weight-average molecular weight of not less than 80,000.

[0056] In some embodiments, the bioactive substance has a high weight-average molecular weight. The spinning solution, by weight, comprises: 5-20 parts by weight of a biodegradable amorphous polymer, 0.1-3 parts by weight of the bioactive substance, 0.5-3 parts by weight of a synthetic water-soluble polymer, 0.01-1.5 parts by weight of an antibacterial agent, and a solvent. The biodegradable amorphous polymer has a weight-average molecular weight of 80,000-300,000; the bioactive substance has a weight-average molecular weight greater than 10,000; the synthetic water-soluble polymer has a weight-average molecular weight of 50,000-500,000; and the low-molecular-weight antibacterial agent has a weight-average molecular weight of 1,000-10,000.

[0057] In this spinning solution, biodegradable amorphous polymers and bioactive substances with high weight-average molecular weight simultaneously form filaments. Organic antibacterial agents, with their smaller molecular weight, cannot form filaments but instead form short linear or granular substances on the electrospinning membrane. When the electrospinning membrane is applied to damaged tissue, the presence of exudate at the site, combined with prolonged application, causes the biodegradable amorphous polymers to absorb water and swell, leading to a slippage of the amorphous molecular chains. This lowers the glass transition temperature of the biodegradable amorphous polymers to body temperature (36℃~38℃) or below, causing the electrospinning membrane to shrink. After shrinkage, the short linear or granular organic antibacterial agents are partially encapsulated within the shrunken membrane, hindering their effectiveness and making it difficult to inhibit bacterial growth. Meanwhile, the bioactive substances form filaments and shrink together with the electrospinning membrane, allowing them to maintain their performance. While bioactive substances can promote cell proliferation, they can also promote bacterial division, and the poor performance of the antibacterial agents themselves can actually increase the bacterial load in the exudate. Increasing the amount of antibacterial agent will negatively impact the biocompatibility of the electrospun membrane. Therefore, this application adds a synthetic water-soluble polymer with a high weight-average molecular weight. This polymer can simultaneously form filaments with biodegradable amorphous polymers and bioactive substances during the electrospinning process. Exudate from damaged tissue preferentially combines with the synthetic water-soluble polymer to cause swelling, while exudate from damaged tissue is less likely to combine with biodegradable amorphous polymers for swelling. The synthetic water-soluble polymer also helps stabilize the fibrous structure, improving the shrinkage of the electrospun membrane and allowing the antibacterial agent to perform better. At the same time, the bioactive substances can promote cell proliferation, making the electrospun membrane beneficial for tissue repair and regeneration.

[0058] For example, the weight-average molecular weight of in vivo degradable amorphous polymers is 80,000, 100,000, 120,000, 140,000, 160,000, 180,000, 200,000, 220,000, 240,000, 260,000, 280,000, or 300,000; the weight-average molecular weight of synthetic water-soluble polymers is 50,000, 100,000, 150,000, 200,000, 250,000, 300,000, 350,000, 400,000, 450,000, or 500,000; the weight-average molecular weight of bioactive substances is 10,000, 50,000, 100,000, 150,000, 200,000, 250,000, 300,000, 350,000, 400,000, 450,000, or 500,000; and the weight-average molecular weight of organic antibacterial agents is 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, or 10,000.

[0059] Optionally, the weight-average molecular weight of the biodegradable amorphous polymer is 100,000 to 300,000; the weight-average molecular weight of the bioactive substance and the synthetic water-soluble polymer is 50,000 to 300,000. The relatively uniform weight-average molecular weight of the three fibrous polymers allows for the formation of a more uniform electrospun film, further mitigating the problem of incomplete antibacterial agent performance due to electrospun film shrinkage, thus resulting in better performance of both the antibacterial agent and the bioactive substance. It should be noted that the weight-average molecular weight of both the bioactive substance and the synthetic water-soluble polymer being 50,000 to 300,000 does not mean that their weight-average molecular weights are the same; they can be the same or different, and this application does not impose any limitation.

[0060] In other embodiments, the bioactive substance has a low weight-average molecular weight. The spinning solution, by weight, comprises: 5-20 parts by weight of a biodegradable amorphous polymer, 0.1-3 parts by weight of the bioactive substance, 0.5-3 parts by weight of a synthetic water-soluble polymer, 0.01-1.5 parts by weight of an antibacterial agent, and a solvent. The biodegradable amorphous polymer has a weight-average molecular weight of 80,000-300,000; the bioactive substance has a weight-average molecular weight of 1,000-10,000; the synthetic water-soluble polymer has a weight-average molecular weight of 50,000-500,000; and the low-molecular-weight antibacterial agent has a weight-average molecular weight of 1,000-10,000.

[0061] In the spinning solution, biodegradable amorphous polymers form filaments. However, the molecular weight of organic antibacterial agents and bioactive substances is too small to form filaments. Instead, they form short linear or granular substances on the electrospinning membrane. When the electrospinning membrane is used to cover or fill damaged tissue, the environment at the damaged tissue contains exudate. If the covering or filling time is long, the biodegradable amorphous polymer will absorb water and swell, causing the amorphous molecular chains to slip. This results in the glass transition temperature of the biodegradable amorphous polymer dropping to or below the body temperature (36℃~38℃), causing the electrospinning membrane to shrink. After shrinkage, some of the short linear or granular organic antibacterial agents and bioactive substances are encapsulated within the shrunken membrane, preventing them from performing their functions effectively and reducing their ability to inhibit bacterial growth and promote cell proliferation. Increasing the amount of antibacterial agents and bioactive substances can lead to poor biocompatibility of the electrospun membrane. Therefore, this application adds a synthetic water-soluble polymer with a high weight-average molecular weight. This polymer can simultaneously form filaments with biodegradable amorphous polymers and bioactive substances during the electrospinning process. Exudate from damaged tissue preferentially combines with the synthetic water-soluble polymer to cause swelling, while exudate from damaged tissue is less likely to combine with biodegradable amorphous polymers to cause swelling. The synthetic water-soluble polymer also plays a role in stabilizing the filamentous structure, improving the shrinkage of the electrospun membrane, and allowing the antibacterial agents and bioactive substances to perform better. This can inhibit bacterial growth and promote cell proliferation, making the electrospun membrane beneficial for tissue repair and regeneration.

[0062] For example, the weight-average molecular weight of in vivo degradable amorphous polymers is 80,000, 100,000, 120,000, 140,000, 160,000, 180,000, 200,000, 220,000, 240,000, 260,000, 280,000, or 300,000; the weight-average molecular weight of synthetic water-soluble polymers is 50,000, 100,000, 150,000, 200,000, 250,000, 300,000, 350,000, 400,000, 450,000, or 500,000; the weight-average molecular weight of bioactive substances is 1,000, 3,000, 5,000, 7,000, 9,000, or 10,000; and the weight-average molecular weight of organic antibacterial agents is 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, or 10,000.

[0063] Optionally, the weight-average molecular weight of the biodegradable amorphous polymer is 100,000 to 300,000; the weight-average molecular weight of the synthetic water-soluble polymer is 100,000 to 300,000; and the weight-average molecular weight of the bioactive substance is 1,000 to 10,000. The relatively uniform weight-average molecular weight of the two types of fibrous materials allows for the formation of a more uniform electrospun film, further mitigating the problem of incomplete antibacterial agent performance due to electrospun film shrinkage, thus resulting in better performance of both the antibacterial agent and the bioactive substance. It should be noted that the weight-average molecular weight of both the biodegradable amorphous polymer and the synthetic water-soluble polymer being 100,000 to 300,000 does not mean that their weight-average molecular weights are the same; they can be the same or different, and this application does not impose any limitation.

[0064] In other embodiments, the weight-average molecular weight of the in vivo degradable amorphous polymer can also be 320,000, 340,000, 360,000, 380,000, 400,000, 420,000, 440,000, 460,000, 480,000, or 500,000; the weight-average molecular weight of the synthetic water-soluble polymer can be 520,000, 540,000, 560,000, 580,000, or 600,000; and the weight-average molecular weight of the organic antibacterial agent can also be 500, 600, 700, 800, or 900. The weight-average molecular weight of the bioactive substance can also be 550,000 or 600,000.

[0065] As an example, by weight, the in vivo degradable amorphous polymer X in the spinning solution can be 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, or 20 parts; the bioactive substance Y1 can be 0.1 parts, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, or 3 parts; the water-soluble polymer Y2 can be 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, or 3 parts; and the antibacterial agent Y3 can be 0.1 parts, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, or 5 parts.

[0066] Optionally, the spinning solution includes: 5-20 parts by weight of a biodegradable amorphous polymer, 0.1-2 parts by weight of a bioactive substance, 0.5-2 parts by weight of a synthetic water-soluble polymer, and 0.1-1.5 parts by weight of an antibacterial agent. Adding a small amount of the synthetic water-soluble polymer can effectively suppress the shrinkage of the electrospun membrane, thus allowing the properties of both the bioactive substance and the antibacterial agent to be fully utilized after adding a small amount, thereby improving the overall performance of the electrospun membrane.

[0067] Furthermore, the weight percentage X of the biodegradable amorphous polymer is greater than the sum of the weight percentages Y of the bioactive substance, the synthetic water-soluble polymer, and the antibacterial agent (Y = Y1 + Y2 + Y3). The biodegradable amorphous polymer is the main component of the spinning solution, which improves the biocompatibility and degradation effect of the electrospun membrane. Moreover, when combined with the synthetic water-soluble polymer, even with very small amounts of antibacterial agent and bioactive substance added, the performance of both can be fully realized.

[0068] Furthermore, X > 5 × Y. This allows the bioactive substances and antibacterial agents to exert their effects effectively, while also ensuring that the electrospun membrane has excellent biocompatibility and biodegradability.

[0069] In some embodiments, the in vivo degradable amorphous polymer includes at least one of racemic polylactic acid and polylactic-glycolic acid copolymer. This material is selected for its good in vivo degradability and biocompatibility, making it suitable as a major component of electrospun membranes for use in the repair of damaged tissues.

[0070] In this application, the specific composition of the biodegradable amorphous polymer is not limited, as long as it is a biodegradable and biocompatible amorphous polymer.

[0071] In some embodiments, the bioactive substance includes at least one selected from collagen, growth factors, silk fibroin, corn protein, gelatin, and hyaluronic acid. The selection of the above-mentioned bioactive substances has a good effect on promoting cell proliferation, thereby enabling the electrospun membrane to promote tissue repair and regeneration.

[0072] Bioactive substances may be water-soluble or water-insoluble. In some embodiments, the bioactive substance is water-soluble (e.g., one or more of growth factors, gelatin, and hyaluronic acid), and can be added to the spinning solution both as a bioactive substance and as a water-soluble polymer. Adding a water-soluble bioactive substance and a water-soluble polymer simultaneously simplifies the composition of the spinning solution. In other embodiments, even if a water-soluble bioactive substance is added to the spinning solution, a synthetic water-soluble polymer can also be added.

[0073] In some embodiments, among the bioactive substances, collagen, silk fibroin, corn protein, gelatin, and hyaluronic acid are bioactive substances with a weight-average molecular weight greater than or equal to 10,000. Among the bioactive substances, growth factors and enzymatically cleaved oligomeric sodium hyaluronate are bioactive substances with a weight-average molecular weight less than 10,000.

[0074] This application does not limit the specific components of the bioactive substance, as long as it is a bioactive substance that can promote cell proliferation.

[0075] In some embodiments, the synthetic water-soluble polymer includes at least one of polyethylene oxide, polyethylene glycol, polyvinyl alcohol, polyacrylamide, and polyvinylpyrrolidone. These polymers are synthetic water-soluble polymers, and adding small amounts of the above components can effectively improve the anti-shrinkage effect of the electrospun film, allowing the antibacterial agents and bioactive substances to perform better.

[0076] In this application, the composition of the synthetic water-soluble polymer is not limited, as long as it is a polymer that can improve the shrinkage properties of an electrospun film whose main component is an in vivo degradable amorphous polymer.

[0077] In some embodiments, the low-molecular-weight antibacterial agent includes inorganic and / or organic antibacterial agents. Since these antibacterial agents have relatively small molecular weights, their effectiveness is compromised if the electrospun membrane shrinks. Therefore, the antibacterial agent is combined with other components in the spinning solution to ensure its optimal effectiveness.

[0078] Among them, inorganic antibacterial agents include at least one of silver sulfate, zinc oxide, copper oxide, ammonium dihydrogen phosphate, and lithium carbonate.

[0079] Organic antimicrobial agents include at least one of guanidine antimicrobial agents, β-lactam antimicrobial agents, and quaternary ammonium salt antimicrobial agents.

[0080] In some embodiments, guanidine antimicrobial agents include at least one of polyhexamethylene guanidine, polyhexamethylene biguanide, polyaminopropyl biguanide, and dodecyl guanidine acetate. β-lactam antimicrobial agents include penicillin and / or cephalosporins. Quaternary ammonium salt antimicrobial agents include at least one of alkyltrimethylammonium chloride, alkyldimethylbenzylammonium chloride, and tetradecyl-2-methylpyridineammonium bromide. These antimicrobial agents are organic antimicrobial agents, and after electrospinning, they tend to form more short threads. The shrinkage of the electrospinning film has a relatively smaller impact on the performance of the antimicrobial agent (compared to inorganic antimicrobial agents). Therefore, when combined with other components in the spinning solution (e.g., synthetic water-soluble polymers), the effect of organic antimicrobial agents can be better exerted.

[0081] This application does not limit the specific components of the antibacterial agent; any antibacterial agent with antibacterial properties that can be applied to spinning solution is within the scope of protection of this application.

[0082] In some embodiments, the solvent includes one or more of hexafluoroisopropanol, chloroform, dichloromethane, trifluoroacetic acid, dimethyl sulfoxide, tetrahydrofuran, dimethylformamide, acetic acid, water, methanol, ethanol, and isopropanol. These solvents can effectively dissolve other components in the spinning solution, which is beneficial for the subsequent formation of an electrospun film via electrospinning. If the solvent is only water, it cannot dissolve all the components in the spinning solution, but it can be combined with other solvents to dissolve other components in the spinning solution. The choice of one or more solvents in this application is related to the selection of other components in the spinning solution, and those skilled in the art can adjust the solvent according to the actual situation.

[0083] In this application, the composition of the solvent is not limited. Any solvent that can dissolve other components in the spinning solution is within the scope of protection of this application.

[0084] In some embodiments, the solute mass percentage of the spinning solution is 5% to 30%. The solute is any substance in the spinning solution other than the solvent, and the solute mass percentage is calculated as solute / (solute + solvent) × 100%.

[0085] When the solute mass ratio of the spinning solution is within the above range, it is easy to form fibers through electrospinning equipment. Furthermore, the fiber structure of the electrospinning membrane can simulate the extracellular matrix, which is beneficial to tissue repair and regeneration when covering or filling damaged tissues.

[0086] As an example, the solute mass percentage of the spinning solution is 5%, 10%, 15%, 20%, 25%, or 30%. Optionally, the solute mass percentage of the spinning solution is 10% to 20%.

[0087] Preparation method of spinning solution

[0088] This application provides a method for preparing a spinning solution, wherein other components of the aforementioned spinning solution are dispersed in a solvent. The components of the spinning solution are those described above; therefore, the composition of the spinning solution will not be elaborated further here, and the preparation method will be the primary focus.

[0089] In some embodiments, a biodegradable amorphous polymer is first dispersed in a solvent to form a mixture 1, and then a bioactive substance, a synthetic water-soluble polymer, and an antibacterial agent are added and dispersed together in the mixture 1 to form a spinning solution. A higher amount of the biodegradable amorphous polymer, which is first dissolved and dispersed in the solvent, followed by the dissolution and dispersion of other components, results in better dissolution and dispersion of the spinning solution, leading to a more uniform spinning solution.

[0090] In other embodiments, each component may be dispersed separately in a solvent and then mixed together to form a spinning solution. Alternatively, other components may be dispersed in a solvent first, followed by the dispersion of in vivo degradable amorphous polymers, etc.

[0091] Electrospinning method

[0092] This application provides an electrospinning method using the aforementioned spinning solution, comprising: spraying the solution onto a receiving device under the conditions of a spinning voltage of 5kV to 30kV and a spinning solution flow rate of 0.2ml / h to 1ml / h. The electrospinned membrane obtained under these spinning conditions is suitable for covering or filling damaged tissue sites, promoting cell proliferation, and effectively inhibiting bacterial growth, thereby accelerating tissue repair and regeneration.

[0093] As an example, the spinning voltage is 5kV, 10kV, 15kV, 20kV, 25kV, or 30kV; the spinning solution flow rate is 0.2ml / h, 0.4ml / h, 0.6ml / h, 0.8ml / h, or 1ml / h. Optionally, the spinning voltage is 5kV to 20kV; the spinning solution flow rate is 0.4ml / h to 0.8ml / h.

[0094] In some embodiments, the temperature of the spinning environment is 20°C to 35°C, and the humidity is 35% to 60%. Spinning under these temperature and humidity conditions can make the spinning more stable and is conducive to the formation of a stable electrospun film.

[0095] As an example, the temperature of the spinning environment is 20°C, 22°C, 25°C, 28°C, 30°C, 32°C, or 35°C; and the humidity is 35%, 40%, 45%, 50%, 55%, or 60%.

[0096] In some embodiments, the receiving device is a receiving roller, and the rotational speed of the receiving roller is 300 r / min to 3000 r / min. This can make the nanofiber distribution of the electrospun membrane more uniform and is beneficial to the evaporation of solvent in the spinning solution during the spinning process.

[0097] As an example, the rotational speed of the receiving roller is 300 r / min, 500 r / min, 800 r / min, 1000 r / min, 1200 r / min, 1500 r / min, 1800 r / min, 2000 r / min, 2200 r / min, 2500 r / min, 2800 r / min, or 3000 r / min. Optionally, the rotational speed of the receiving roller is 500 r / min to 2000 r / min.

[0098] Electrospun film

[0099] This application provides an electrospun membrane, obtained from the aforementioned spinning solution using the aforementioned electrospun method. The electrospun membrane prepared by this method has good biocompatibility and can improve the shrinkage of the electrospun membrane. It is suitable for covering or filling damaged tissues, which is beneficial for promoting cell proliferation and can also effectively inhibit bacterial growth, thereby accelerating tissue repair and regeneration.

[0100] In other embodiments, the spinning solution can also be formed on the receiving device by coating to form a film. The spinning solution in this application is not limited to film formation via electrospinning; film formation by other spinning or coating methods is also within the scope of protection of this application.

[0101] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0102] Example 1

[0103] A spinning solution, by weight, comprises: 20g poly(lactic-co-glycolic acid) copolymer (PLGA, weight average molecular weight 100,000), 0.4g hydrolyzed collagen (Col, Collagen, weight average molecular weight 200,000), 1g polyethylene oxide (PEO, Polyethylene oxide, weight average molecular weight 400,000), 0.3g polyhexamethylene biguanide hydrochloride (PHMB, weight average molecular weight 1,500), and 78.3g hexafluoroisopropanol (HFIP).

[0104] Methods for preparing spinning solutions include:

[0105] Step 1: Weigh 20g of polylactic acid-glycolic acid copolymer particles into 82.3g of hexafluoroisopropanol using a precision electronic balance, add a magnetic stir bar, and stir at room temperature until clear and transparent to obtain a PLGA solution;

[0106] Step 2: Weigh 0.4g of hydrolyzed collagen lyophilized tablets, 1g of polyethylene oxide powder, and 0.3g of polyhexamethylene biguanide hydrochloride powder into the PLGA solution obtained in Step 1 using a precision electronic balance, and stir at room temperature until clear and transparent to obtain PHMB / Col / PEO / PLGA spinning solution.

[0107] Step 3: Take the above PHMB / Col / PEO / PLGA spinning solution into a syringe, fix the syringe to the electrospinning machine's injection pump, attach the needle connected to the positive terminal of the high-voltage power supply, and connect the receiving roller to the negative terminal of the high-voltage power supply. Set the spinning parameters: spinning voltage 10kV, spinning solution flow rate 0.5ml / h, receiving roller speed 800r / min, temperature 28℃, humidity 58%.

[0108] Step 4: Dry the nanofiber material prepared by spinning above at room temperature for 12 hours to obtain PHMB / Col / PLGA (containing PEO) nanofiber membrane.

[0109] Example 2

[0110] Example 2 is basically the same as Example 1, except that: the polylactic acid-glycolic acid copolymer in Example 1 is replaced with racemic polylactic acid (PDLLA, Poly(D,L-lactide), D,L-polylactide, weight-average molecular weight of 100,000) powder in Example 2; and the solvent hexafluoroisopropanol in Example 1 is replaced with tetrahydrofuran in Example 2.

[0111] Example 3

[0112] Example 3 is basically the same as Example 1, except that polyethylene oxide is not added.

[0113] Example 4

[0114] Example 4 is basically the same as Example 1, except that the polyethylene oxide powder in Example 1 is replaced with polyvinyl alcohol (PVA, Polyvinyl alcohol, weight average molecular weight of 80,000) powder in Example 4.

[0115] Example 5

[0116] Example 5 is basically the same as Example 1, except that the polyethylene oxide powder in Example 1 is replaced with polyvinyl pyrrolidone (PVP, weight-average molecular weight of 60,000) powder in Example 5.

[0117] Example 6

[0118] Example 6 is basically the same as Example 1, except that the collagen freeze-dried tablets in Example 1 are replaced with 2g of gelatin (Gel, Gelatin, weight average molecular weight of 80,000) particles in Example 6, and the amount of polyhexamethylene biguanide hydrochloride added is 0.1g.

[0119] Example 7

[0120] Example 7 is basically the same as Example 1, except that the collagen in Example 1 is replaced with 0.5g of fibroblast growth factor (FGF, weight average molecular weight of 6,000) lyophilized powder in Example 7, and the amount of polylactic acid-glycolic acid copolymer added is 10g.

[0121] Example 8

[0122] Example 8 is basically the same as Example 1, except that the polyhexamethylene biguanide hydrochloride in Example 1 is replaced with 0.01g of amoxicillin (molecular weight 365.4) in Example 8, and the amount of polylactic acid-glycolic acid copolymer added is 10g.

[0123] Example 9

[0124] Example 9 is basically the same as Example 1, except that the polyhexamethylene biguanide hydrochloride in Example 1 is replaced with 0.01g of silver sulfate (molecular weight 169.87) in Example 9, and the amount of polylactic acid-glycolic acid copolymer added is 18g.

[0125] Examples 10-11

[0126] Examples 10 and 11 are basically the same as Example 1, except that the amount of each component added is different, as shown in Table 1.

[0127] Example 12

[0128] A spinning solution, by weight, comprises: 10g poly(lactic-co-glycolic acid) copolymer (PLGA, weight average molecular weight 100,000), 0.4g collagen (Col, weight average molecular weight 200,000), 3g polyethylene oxide (PEO, weight average molecular weight 400,000), 0.3g polyhexamethylene biguanide hydrochloride (PHMB, weight average molecular weight 1,500), and 86.3g hexafluoroisopropanol (HFIP).

[0129] Methods for preparing spinning solutions include:

[0130] Step 1: Weigh 10g of polylactic acid-glycolic acid copolymer particles into 86.3g of hexafluoroisopropanol using a precision electronic balance, add a magnetic stir bar, and stir at room temperature until clear and transparent to obtain a PLGA solution;

[0131] Step 2: Weigh 0.4g of collagen, 3g of polyethylene oxide powder, and 0.3g of polyhexamethylene biguanide hydrochloride powder into the PLGA solution obtained in Step 1 using a precision electronic balance, and stir at room temperature until clear and transparent to obtain PHMB / Col / PEO / PLGA spinning solution;

[0132] Step 3: Take the above PHMB / Col / PEO / PLGA spinning solution into a syringe, fix the syringe to the electrospinning machine's injection pump, attach the needle connected to the positive terminal of the high-voltage power supply, and connect the receiving roller to the negative terminal of the high-voltage power supply. Set the spinning parameters: spinning voltage 10kV, spinning solution flow rate 0.5ml / h, receiving roller speed 800r / min, temperature 28℃, humidity 58%.

[0133] Step 4: Dry the nanofiber material prepared by spinning above at room temperature for 12 hours to obtain PHMB / Col / PLGA (containing PEO) nanofiber membrane.

[0134] Comparative Example 1

[0135] A spinning solution comprising, by weight: 16g of poly(lactic-co-glycolic acid) copolymer (PLGA, with a weight-average molecular weight of 100,000) and 84g of hexafluoroisopropanol (HFIP).

[0136] Methods for preparing spinning solutions include:

[0137] Step 1: Weigh 16g of polylactic acid-glycolic acid copolymer particles into 84g of hexafluoroisopropanol using a precision electronic balance, add a magnetic stir bar, and stir at room temperature until clear and transparent to obtain a PLGA solution.

[0138] Step 2: Take the above PLGA solution into a syringe, fix the syringe to the injection pump of the electrospinning machine, attach the needle connected to the positive terminal of the high-voltage power supply, and connect the receiving roller to the negative terminal of the high-voltage power supply. Set the spinning parameters: spinning voltage is 10kV, spinning solution flow rate is 0.5ml / h, receiving roller speed is 800r / min, temperature is 28℃, and humidity is 58%.

[0139] Step 3: Dry the nanofiber material prepared by spinning above at room temperature for 12 hours to obtain PLGA nanofiber membrane.

[0140] Comparative Example 2

[0141] A spinning solution comprises, by weight: 16g poly(lactic-co-glycolic acid) copolymer (PLGA, weight average molecular weight 100,000), 0.5g polyhexamethylene biguanide hydrochloride (PHMB, weight average molecular weight 1,500), and 83.5g hexafluoroisopropanol (HFIP).

[0142] Methods for preparing spinning solutions include:

[0143] Step 1: Weigh 16g of polylactic acid-glycolic acid copolymer particles into 83.5g of hexafluoroisopropanol using a precision electronic balance, add a magnetic stir bar, and stir at room temperature until clear and transparent to obtain a PLGA solution;

[0144] Step 2: Weigh 0.5g of polyhexamethylene biguanide hydrochloride powder into the PLGA solution obtained in Step 1 using a precision electronic balance, and stir at room temperature until clear and transparent to obtain PHMB / PLGA spinning solution;

[0145] Step 3: Take the above PHMB / PLGA spinning solution into a syringe, fix the syringe to the injection pump of the electrospinning machine, attach the needle connected to the positive terminal of the high-voltage power supply, and connect the receiving roller to the negative terminal of the high-voltage power supply. Set the spinning parameters: spinning voltage is 10kV, spinning solution flow rate is 0.5ml / h, receiving roller speed is 800r / min, temperature is 28℃, and humidity is 58%.

[0146] Step 4: Dry the nanofiber material prepared by spinning above at room temperature for 12 hours to obtain PHMB / PLGA nanofiber membrane.

[0147] Comparative Example 3

[0148] A spinning solution comprising, by weight: 16g of polyvinyl butyral (PVB, weight-average molecular weight of 100,000) and 84g of an aqueous ethanol solution.

[0149] Methods for preparing spinning solutions include:

[0150] Step 1: Weigh 16g of polyvinyl butyral granules into 84g of ethanol aqueous solution using a precision electronic balance, add a magnetic stir bar, and stir at room temperature until clear and transparent to obtain a PVB solution.

[0151] Step 2: Take the above PVB solution into a syringe, fix the syringe to the injection pump of the electrospinning machine, attach the needle connected to the positive terminal of the high-voltage power supply, and connect the receiving roller to the negative terminal of the high-voltage power supply. Set the spinning parameters: spinning voltage is 10kV, spinning solution flow rate is 0.5ml / h, receiving roller speed is 800r / min, temperature is 28℃, and humidity is 58%.

[0152] Step 3: Dry the nanofiber material prepared by spinning above at room temperature for 12 hours to obtain PVB nanofiber membrane.

[0153] Experimental Example 1

[0154] The performance of the electrospun films provided in Examples 1 to 12 and Comparative Examples 1 to 3 was tested, and the results are shown in Table 1.

[0155] (1) Antibacterial performance was tested according to GB / T 20944.1-2007 standard, using ATCC8739 Escherichia coli (E. coli) as the test strain. The antibacterial performance was evaluated by the size of the inhibition zone formed after the sample was added. The inhibition zone refers to the area in which no bacteria grow and the growth of surrounding bacteria is inhibited. The larger the inhibition zone, the better the antibacterial performance.

[0156] The specific method is as follows: All samples were first cut into circles with a diameter of 3.55 cm and sterilized by irradiation under a UV lamp for 2 hours. Sterile nutrient agar was then poured into sterile petri dishes and cooled under UV sterilization for later use. Subsequently, 150 μl of bacterial suspension (concentration of 10) was taken... 5 CFU was evenly inoculated onto the culture medium, and the sterilized samples were placed in the center of the agar plate and placed in a biological incubator at 37±1℃ for 24 hours.

[0157] Determining the antibacterial zone: First, observe whether there is an area around the electrospun membrane where no bacteria grow. If there is, it means that bacteria stop growing when they reach the outer ring of that area, proving a significant antibacterial effect. The antibacterial area is the area of ​​the outer ring. If not, continue to irradiate the electrospun membrane area with a point light source and check whether there are colonies in the membrane-covered area. If there are, it means that the membrane has no antibacterial effect, and the antibacterial area is 0. If not, it means that bacteria have not entered the membrane-covered area to grow, proving that the membrane has a certain antibacterial effect and can prevent bacteria from entering the dressing and growing inside.

[0158] The antibacterial properties of some samples are shown in the figure below. Figure 1 ,in, Figure 1 The inner ring in the petri dish represents the electrospun membrane, and the gray area around the inner ring represents the inhibition zone. Figure 1As can be seen, compared with Examples 1 and 10, the PLGA electrospun membranes provided in Comparative Examples 1 and 2 show significant shrinkage and do not form an antibacterial zone, thus lacking antibacterial properties. Therefore, Comparative Example 1 shows that the PLGA electrospun membrane provided in Comparative Example 1 is prone to shrinkage and lacks antibacterial properties; Comparative Example 2 shows that even with the addition of PHMB antibacterial agent to the PLGA electrospun membrane, the resulting electrospun membrane still exhibits significant shrinkage, and the antibacterial agent's performance is not realized, resulting in no antibacterial effect; Examples 1 and 10 show that adding the synthetic water-soluble polymer polyethylene oxide to the electrospun membrane can significantly improve the shrinkage of the electrospun membrane and effectively enhance its antibacterial effect.

[0159] (2) Cell viability experiment

[0160] The L929 mouse fibroblast cell line was used for cell viability assays. Experimental groups consisted of the test samples, while the control group contained no samples. First, the experimental groups were placed in 12-well tissue culture plates and sterilized under UV light for 2 hours. Then, L929 cells (1×10⁻⁶) were... 5 Cells ( / mL) were seeded into 12-well tissue culture plates (12 parallel experiments were performed for each sample, and the test structures were analyzed as shown in Table 1). All samples were incubated in a 37℃, 5% CO2 incubator for 72 hours. After incubation, the absorbance at 570 nm for each group was measured using the MTT assay with a microplate reader. The cell proliferation rate of each experimental group was obtained by calculating the absorbance ratio. A higher cell proliferation rate indicates better cell viability, i.e., a stronger ability to promote tissue repair; if the cell proliferation rate is less than 100%, the sample is considered cytotoxic.

[0161] Table 1. Composition of spinning solution and performance of electrospun film

[0162]

[0163] As shown in Table 1, in Comparative Example 3, PVB caused certain cytotoxicity, affecting cell growth. Comparing Comparative Examples 1 and 2, PLGA exhibits good biocompatibility, does not produce cytotoxicity, and the electrospun nanofiber structure also promotes cell activity. However, when PLGA is used as the main component of the spinning solution, even with the addition of the antibacterial agent PHMB, the resulting electrospun membrane has virtually no antibacterial effect. In Examples 1 to 12 of this application, when a biodegradable amorphous polymer is used as the main component of the spinning solution, the addition of a small amount of water-soluble polymer and antibacterial agent can increase the antibacterial area of ​​the electrospun membrane, allowing the antibacterial agent to perform better.

[0164] A comparison of Examples 1 and 2 shows that PLGA or PDLLA, which are biodegradable amorphous polymers, can be combined with synthetic water-soluble polymers (PEO), bioactive substances (Col, natural water-soluble polymers), and antibacterial agents (PHMB) to improve the performance of antibacterial agents and bioactive substances. This can inhibit bacterial growth (larger antibacterial area) and promote cell proliferation (high cell proliferation rate), which is beneficial for tissue repair and regeneration.

[0165] A comparison of Examples 1 and 3 shows that, when the biodegradable amorphous polymer PLGA is used as the main component of the spinning solution, compared to Example 3 which only added a bioactive substance (Col, a natural water-soluble polymer), Example 1 simultaneously added a synthetic water-soluble polymer (PEO) and a bioactive substance (Col, a natural water-soluble polymer). This can further enhance the performance of the antibacterial agent and the bioactive substance, further inhibit bacterial growth (with a larger antibacterial area), and further promote cell proliferation, which is beneficial for tissue repair and regeneration.

[0166] A comparison of Examples 1 and 4 to 9 shows that the selection of PEO, PVA, or PVP as the synthetic water-soluble polymer, Col, gelatin, or FGF as the bioactive substance, and PHMB, amoxicillin, or silver sulfate as the antibacterial agent can effectively inhibit bacterial growth and promote cell proliferation, which is beneficial for tissue repair and regeneration.

[0167] The embodiments described above are some, but not all, of the embodiments of this application. The detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

Claims

1. A spinning solution, characterized in that, Based on parts by weight, the product comprises: 5-20 parts by weight of a biodegradable amorphous polymer, 0.1-2 parts by weight of a bioactive substance, 0.5-2 parts by weight of a synthetic water-soluble polymer, 0.1-1.5 parts by weight of a low-molecular-weight antibacterial agent, and a solvent; wherein the biodegradable amorphous polymer comprises at least one of racemic polylactic acid and polylactic acid-glycolic acid copolymer, and the synthetic water-soluble polymer comprises at least one of polyethylene oxide, polyethylene glycol, polyvinyl alcohol, polyacrylamide, and polyvinylpyrrolidone; The weight part of the biodegradable amorphous polymer is X, and the sum of the weight parts of the bioactive substance, the synthetic water-soluble polymer and the antibacterial agent is Y, where X > 5 × Y; The weight-average molecular weight of the biodegradable amorphous polymer is not less than 80,000, the weight-average molecular weight of the synthetic water-soluble polymer is not less than 50,000, the weight-average molecular weight of the bioactive substance is greater than 10,000, and the weight-average molecular weight of the low-molecular-weight antibacterial agent is not greater than 10,000.

2. The spinning solution according to claim 1, characterized in that, The weight-average molecular weight of the biodegradable amorphous polymer is 80,000 to 300,000; the weight-average molecular weight of the synthetic water-soluble polymer is 50,000 to 500,000; and the weight-average molecular weight of the low-molecular-weight antibacterial agent is 1,000 to 10,000.

3. The spinning solution according to claim 1, characterized in that, The weight-average molecular weight of the biodegradable amorphous polymer is 80,000 to 300,000; the weight-average molecular weight of the bioactive substance is 1,000 to 10,000; the weight-average molecular weight of the synthetic water-soluble polymer is 50,000 to 500,000; and the weight-average molecular weight of the low-molecular-weight antibacterial agent is 1,000 to 10,000.

4. The spinning solution according to any one of claims 1 to 3, characterized in that, The spinning solution satisfies at least one of the following conditions: a) The bioactive substances include at least one of collagen, growth factors, silk fibroin, corn protein, gelatin and hyaluronic acid; b) The antimicrobial agents include organic antimicrobial agents and / or inorganic antimicrobial agents.

5. The spinning solution according to claim 4, characterized in that, The organic antibacterial agent includes at least one of guanidine antibacterial agents, β-lactam antibacterial agents, and quaternary ammonium salt antibacterial agents.

6. The spinning solution according to claim 5, characterized in that, The organic antimicrobial agent meets at least one of the following conditions: c) The guanidine antimicrobial agents include at least one of polyhexamethylene guanidine, polyhexamethylene biguanide, polyaminopropyl biguanide, and dodecyl guanidine acetate; d) The β-lactam antibacterial agents include penicillin and / or cephalosporins; e) The quaternary ammonium salt antibacterial agent includes at least one of alkyltrimethylammonium chloride, alkyldimethylbenzylammonium chloride, and tetradecyl-2-methylpyridineammonium bromide.

7. The spinning solution according to any one of claims 1 to 3, characterized in that, The solute mass ratio of the spinning solution is 5% to 30%.

8. A method for preparing an electrospun film, characterized in that, The spinning solution according to any one of claims 1 to 7 is sprayed onto the receiving device under the conditions of a spinning voltage of 5 kV to 30 kV and a spinning solution flow rate of 0.2 ml / h to 1 ml / h.

9. The method for preparing an electrospun film according to claim 8, characterized in that, The spinning environment has a temperature of 20℃~35℃ and a humidity of 35%~60%.

10. The method for preparing the electrospun film according to claim 9, characterized in that, The receiving device is a receiving roller, and the rotational speed of the receiving roller is 300 r / min to 3000 r / min.

11. An electrospun film, characterized in that, The electrospun film is obtained by the preparation method according to any one of claims 8 to 10.

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