A multifunctional medical material and its preparation method and application

Abstract

The present invention relates to a multifunctional medical material and its preparation method and application, wherein the multifunctional medical material is an electrostatic spinning fiber membrane prepared by using materials including a poly-polymer material, a material with anionic groups, collagen and ε-polylysine as raw materials. The medical material has the advantages of both electrostatic spinning membrane and self-assembled membrane, is close to the structure of the extracellular matrix, has a large specific surface area, increases its surface energy and activity, produces a small size effect, and has a surface and interface effect, can provide a large number of cell contact points, provides a better microenvironment for cell adhesion, proliferation, and physiological function, and improves protein adsorption, and contains hydrophilic substances such as collagen in the composition, so that the multifunctional medical material has good hydrophilicity. At the same time, its own good characteristics enable the product to be directly attached and used in clinical use, more effectively induce cell growth and tissue regeneration, and thus effectively promote the repair of wounds, thereby expanding the scope of application.

Description

Technical Field

[0001] The present invention belongs to the technical field of biomedical materials, and specifically relates to a medical material with antibacterial, adhesion-preventing and repair-promoting properties, as well as a preparation method and application thereof. Background Art

[0002] Common problems encountered in surgical operations are preventing infection, preventing adhesions, and promoting wound repair after surgery. Therefore, some biomaterials have emerged, such as the anti-adhesion membranes made of polymer materials used clinically, and the animal tissue decellularized biomaterials that have appeared in recent years. These products provide excellent anti-adhesion or repair-promoting effects on postoperative wounds.

[0003] In recent years, with the development of additive manufacturing technology, electrospinning technology has become a simple, cost-effective method for preparing ultrafine fibers. It can produce micro-nanoscale fibers. The nanofiber structure can well simulate tissue engineering scaffolds, is close to the structure of the extracellular matrix, and has a large specific surface area, which leads to increased surface energy and activity, thereby producing a small size effect. The surface and interface effects can provide a large number of cell contact points, providing a better microenvironment for cell adhesion, proliferation, and physiological function, and improving protein adsorption. It can more effectively induce cell growth and tissue regeneration, and is also more conducive to the release of drugs and biological factors. Therefore, patches prepared by electrospinning technology have gradually appeared in clinical use. However, due to the influence of the spinning material, these patches are mainly composed of polymer materials, so the hydrophilicity and biocompatibility of the patches are lacking. Although some products have improved by adding biomacromolecules such as fibrinogen to the polymer materials, the amount added is limited due to the spinnability of the materials, and the biomacromolecules will inevitably be wrapped inside the fiber filaments, affecting the performance.

[0004] Wounds caused by surgery and trauma are susceptible to microbial infection. Without effective treatment, wound infection can delay healing. While topical anti-infective medications are often used for external wounds, the risk of infection in internal wounds after surgery often requires preventive and therapeutic antibiotic injections. Antibiotic resistance, driven by overuse, has become a widespread and significant problem. Furthermore, medical materials implanted in the human body to prevent adhesions and promote wound repair after surgery can encapsulate. In such cases, infection cannot be resolved even with antibiotic injections due to the lack of capillaries. In the past, researchers have added nanosilver to medical materials for antimicrobial purposes. However, concerns about silver's heavy metal toxicity, cytotoxicity, and skin darkening have led the China Medical Products Administration to exercise caution regarding silver ion materials. The search for materials with excellent antimicrobial properties for implantation in the body is ongoing, particularly materials that simultaneously prevent infection, prevent adhesions, and promote wound repair.

[0005] Collagen is widely present in human and animal tissues. For example, connective tissue contains 60-70% water, of which collagen accounts for approximately 20-30%. Collagen is one of the main components of the extracellular matrix. Due to its good biocompatibility and degradability, and its ability to construct an extracellular matrix microenvironment, it is conducive to cell adhesion and proliferation, can induce the differentiation of bone marrow mesenchymal stem cells, and exhibits certain biological activity and functionality. Therefore, collagen, as an important biomaterial, is widely used in multiple clinical fields and has high practical application value. The main component of animal acellular matrix repair materials used clinically is collagen.

[0006] ε-Polylysine is a polycationic polypeptide that can inhibit Gram-negative bacteria, Gram-positive bacteria, fungi, etc. It has a broad antibacterial spectrum and can even kill some viruses. This substance is a lysine homopolymer produced by microorganisms and is a relatively safe antibacterial agent for the human body. Many countries have widely used it as a food preservative. Further, people are gradually trying to develop it into a safe and effective antibacterial material for human use.

[0007] CN110507842A discloses a bacterial cellulose / hyaluronic acid / ε-polylysine functional dressing and its preparation method. The ε-polylysine and hyaluronic acid are bound by electrostatic forces and fixed within the bacterial cellulose network. This functional dressing boasts high safety, good biocompatibility, and broad-spectrum antimicrobial properties. The preparation method is simple, efficient, environmentally friendly, and does not disrupt the three-dimensional network structure of the bacterial cellulose. However, the electrostatic adsorption process increases the risk of contamination and production costs.

[0008] CN111441101A discloses a method for preparing PLGA / ε-polylysine antibacterial nanofibers, comprising: mixing polylactic acid-glycolic acid copolymer with 2,2,2-trifluoroethanol and stirring to obtain a polylactic acid-glycolic acid copolymer solution; adding ε-polylysine to deionized water and stirring to obtain an ε-polylysine solution; mixing the polylactic acid-glycolic acid copolymer solution with the ε-polylysine solution to obtain a PLGA / ε-polylysine mixed solution; and electrospinning the PLGA / ε-polylysine mixed solution to obtain PLGA / ε-polylysine antibacterial nanofibers. The antibacterial nanofibers prepared by this invention have good antibacterial properties and thermal stability, but a large amount of ε-polylysine is encapsulated inside the fiber. To achieve an antibacterial effect on the surface of the fiber prepared in this way, the ε-polylysine content needs to be increased, and the increased ε-polylysine content will produce cytotoxicity. In addition, the ε-polylysine encapsulated in the fiber filaments is difficult to release completely and will remain in the body with the material for a long time. Over time, it will diffuse to other tissue sites, causing persistent cytotoxicity. Summary of the Invention

[0009] In view of the deficiencies of the prior art, the purpose of the present invention is to provide a multifunctional medical material and a preparation method thereof, which has the functions of inhibiting bacteria, preventing adhesion and promoting repair.

[0010] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0011] In a first aspect, the present invention provides a multifunctional medical material, which is an electrospun fiber membrane prepared using materials including polymer materials, materials with anionic groups, collagen and ε-polylysine as raw materials.

[0012] Preferably, the electrospinning adopts coaxial electrospinning technology, and the fibers in the electrospun fiber membrane include a core layer structure and a shell layer structure.

[0013] Preferably, the raw materials for preparing the core layer structure include polymer materials.

[0014] Preferably, the raw materials for preparing the core layer structure also include collagen.

[0015] Preferably, the raw materials for preparing the core layer structure include 5-15 parts (for example, 5 parts, 7 parts, 8 parts, 10 parts, 12 parts, 14 parts or 15 parts, etc.) of polymer material and 1-20 parts (for example, 1 part, 2 parts, 5 parts, 10 parts, 12 parts, 15 parts or 20 parts, etc.) of collagen in parts by mass; other specific point values within the above numerical range can be selected, and they will not be repeated here.

[0016] Further preferably, the raw materials for preparing the core layer structure include 8-12 parts by mass of polymer material and 1-10 parts of collagen.

[0017] Preferably, the raw materials for preparing the shell structure include polypolymer materials, and also include any one or a combination of at least two of polypolymer materials, materials with anionic groups, collagen or ε-polylysine.

[0018] Preferably, the raw materials for preparing the shell structure include polymer materials, materials with anionic groups, collagen and ε-polylysine.

[0019] Preferably, the raw materials for preparing the shell structure include, by mass, 0-10 parts of a polymer material but not including 0 (for example, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts or 10 parts, etc.), 0-10 parts of a material with anionic groups but not including 0 (for example, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts or 10 parts, etc.), 0-5 parts of collagen but not including 0 (for example, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, etc.) and 0-10 parts of ε-polylysine but not including 0 (for example, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts or 10 parts, etc.); other specific point values within the above numerical range can be selected, and they will not be repeated here.

[0020] Further preferably, the raw materials for preparing the shell structure include, by mass, 1-5 parts of polymer material, 0.1-6 parts of material with anionic groups, 0.2-3 parts of collagen and 0.5-5 parts of ε-polylysine.

[0021] The multifunctional medical materials involved in the present invention specifically include two forms of products, namely, ε-polylysine or materials with anionic groups, and the distribution state of the products is slightly different due to different preparation methods. One is that ε-polylysine or materials with anionic groups are used as one of the raw materials of the shell spinning solution, and are distributed in the shell structure of the nano-composite fiber after spinning; the other is that ε-polylysine or materials with anionic groups are evenly distributed on the entire surface of the nano-composite fiber membrane.

[0022] The material involved in the present invention is prepared using electrostatic spinning technology, so the prepared nanofiber structure can well simulate tissue engineering scaffolds, which is beneficial for cell adhesion and growth; secondly, the electrostatic spinning uses a coaxial spinning method, and the core layer and the shell layer are composed of different materials. In order to make the mechanical properties and biological functions of the material meet the needs, the core layer is mainly composed of polypolymer materials, which serve as a three-dimensional network structure skeleton and can provide good mechanical strength. It not only enables the nanofiber membrane to withstand a certain suture force without tearing or peeling, but can also be deformed but not damaged, and exert excellent mechanical properties, and better maintain the three-dimensional network structure skeleton, which is not only beneficial for cell adhesion and growth, but also can better play an isolation and anti-adhesion effect; in order to improve the hydrophilicity and biocompatibility of the polypolymer material, a certain amount of collagen can preferably be added to the core layer spinning solution. Collagen has biocompatibility and promotes tissue regeneration and repair functions; it will be continuously released as the material degrades to enhance its repair function.

[0023] The shell layer primarily comprises ε-polylysine, collagen, and materials with anionic groups. Adding smaller amounts of polymeric materials can increase spinnability. When ε-polylysine is distributed on the fiber surface, it can inhibit bacteria early after surgery, eliminating infection risks. The amount of ε-polylysine added can also be better controlled. Furthermore, ε-polylysine is concentrated on the material surface, achieving a surface concentration that achieves an antibacterial effect. While the overall material concentration is low, it can more effectively exert an antibacterial effect while maintaining low cytotoxicity. Collagen, which promotes tissue repair, is preferably used to simultaneously immobilize the ε-polylysine and collagen components primarily on the fiber surface of a three-dimensional network structure using coaxial electrospinning technology, enabling synergistically exerting excellent antibacterial and repair-promoting properties. Furthermore, since ε-polylysine and collagen carry cationic properties, in order to allow them to be better fixed on the three-dimensional network structure, the present invention specifically adds materials with anionic groups. Due to the electrostatic effect, it will be beneficial for ε-polylysine and / or collagen to be relatively stably fixed on the three-dimensional network structure, so that the product can reduce the occurrence of the sudden release of ε-polylysine or collagen when in use, so that the product can better exert its antibacterial and repair properties at the wound tissue site. At the same time, the electrostatic effect of the material with anionic groups and ε-polylysine and / or collagen can better fix the three-dimensional network structure, and can replace the cross-linking and fixing effect of the cross-linking agent, thereby avoiding the toxic and side effects of the use of the cross-linking agent. In addition, after the material with anionic groups is added, the antibacterial properties of the material as a whole can also be enhanced.

[0024] Preferably, the polymer material comprises any one or a combination of at least two of polylactic acid, polyglycolide, polycaprolactone, polyvinyl alcohol, polylactic-co-glycolic acid, polyethylene glycol, polytetrafluoroethylene, polyesteramide or polyurethane, preferably a combination of polylactic acid and polylactic-co-glycolic acid.

[0025] The combination of at least two of the above mentioned products can be, for example, a combination of polylactic acid and polyglycolide, a combination of polycaprolactone and polyvinyl alcohol, a combination of polylactic acid-glycolic acid copolymer and polyethylene glycol, and any other combination can be selected and will not be described in detail here.

[0026] Preferably, the material with anionic groups includes any one of sodium hyaluronate, carboxymethyl cellulose, carboxymethyl chitosan, sodium alginate, chondroitin sulfate or fibrin, or a combination of at least two thereof, preferably a combination of sodium hyaluronate and sodium alginate.

[0027] The combination of at least two of the above mentioned can be, for example, a combination of sodium hyaluronate and carboxymethyl cellulose, a combination of sodium alginate and chondroitin sulfate, a combination of chondroitin sulfate and fibrin, and any other combinations can be selected and will not be described in detail here.

[0028] Preferably, the collagen includes any one of type I collagen or its active domain, type II collagen or its active domain, type III collagen or its active domain, or a combination of at least two thereof, more preferably type I collagen or type III collagen.

[0029] Preferably, the molecular weight of the ε-polylysine is 3000-5000, for example, 3000, 3200, 3400, 3600, 3800, 4000, 4200, 4300, 4600, 4800 or 5000, preferably 3600-4600, more preferably 3600-4300. Any other specific point value within the above numerical range can be selected, and they will not be described one by one here.

[0030] The molecular weight of the ε-polylysine involved in the present invention is specifically selected to be 3000-5000, preferably 3000-4600, and more preferably 3600-4300, because the antibacterial activity of ε-polylysine is highest when the molecular weight is 3600-4300, and the activity is lost when the molecular weight is less than 1300.

[0031] In a second aspect, the present invention provides a method for preparing the multifunctional medical material as described above, the method comprising the following steps:

[0032] (1) mixing and dissolving a polymer material with a solvent to obtain a core layer spinning solution; optionally, collagen is also dissolved in the core layer spinning solution;

[0033] (2) dissolving the polymer material and collagen in a solvent respectively and then mixing them to obtain a shell spinning solution;

[0034] (3) coaxially spinning the shell layer spinning solution and the core layer spinning solution to prepare the multifunctional medical material, optionally further comprising soaking the multifunctional medical material in water and then drying;

[0035] The shell spinning solution of step (2) or the water of step (3) optionally contains ε-polylysine; the shell spinning solution of step (2) or the water of step (3) optionally contains a material with anionic groups; and the ε-polylysine and the material with anionic groups are not present in the water of step (3) at the same time.

[0036] The preparation method of the multifunctional medical material involved in the present invention has simple process, easy to control product quality, and can realize high-efficiency, low-pollution and low-cost industrial production.

[0037] Preferably, the solvent is selected from any one or a combination of at least two of chloroform, dichloromethane, N,N-dimethylformamide, methanol, ethanol, hexafluoroisopropanol, trifluoroacetonitrile, trifluoroacetic acid, formic acid, acetic acid or acetone.

[0038] The combination of at least two of the above-mentioned compounds can be, for example, a combination of chloroform and dichloromethane, a combination of N,N-dimethylformamide and methanol, a combination of hexafluoroisopropanol and trifluoroacetonitrile, and any other combinations can be selected, which will not be described in detail here.

[0039] Preferably, the concentration of the polymer material in the core layer spinning solution is 5-15%, for example, 5%, 6%, 8%, 9%, 10%, 12%, 13%, 14% or 15%, etc. Other specific point values within this numerical range can be selected and will not be described here one by one. It is more preferably 8-12%.

[0040] Preferably, the concentration of collagen in the core layer spinning solution is 0-5% but does not include 0, such as 0.5%, 1%, 2%, 3%, 4%, 5%, etc. Other specific point values within this numerical range can be selected and will not be repeated here. 0-3% is more preferred.

[0041] The core layer spinning solution of the present invention further contains collagen, which is beneficial to improving the hydrophilicity and repairing function of the nanofiber membrane.

[0042] The concentration of collagen in the core layer spinning solution is specifically selected to be 0-5% because if the concentration is further increased, the viscosity of the spinning solution will increase, the spinning effect will be unsatisfactory, and the mechanical properties of the nanofiber membrane will be affected.

[0043] The concentration of the polymer material in the core layer spinning solution is specifically selected to be 5-15% because a further decrease in the concentration will reduce the mechanical properties and three-dimensional structure of the nanofiber membrane, while a further increase in the concentration will increase the degradation time of the nanofiber membrane. 8-12% is the optimal concentration range to balance the two.

[0044] Preferably, the concentration of the polymer material in the shell spinning solution in step (2) is 0-10%, for example, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc. Any other specific point value within the above numerical range can be selected, and they will not be repeated here. 1-5% is more preferred.

[0045] The concentration of the polymer material in the shell spinning solution is specifically selected to be 1-5% because if the concentration is further increased, it will affect the proportion of other components in the spinning solution system, and if it is further reduced, it will affect the spinning morphology.

[0046] Preferably, the concentration of the material with anionic groups in the shell spinning solution is 0-10% but not including 0, for example 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., preferably 0.1-6%, and any other specific point value within the above numerical range can be selected, and they will not be repeated here.

[0047] The weight percentage of the material with anionic groups in the shell spinning solution is specifically selected to be 0.1-6% because increasing its concentration would increase the viscosity of the spinning solution, making it difficult to spin, while decreasing its concentration would affect its binding to ε-polylysine and collagen. The 0.1-6% concentration range is the optimal balance between these two.

[0048] Preferably, the concentration of collagen in the shell spinning solution is 0-10%, more preferably 0.2-5%, for example 0.2%, 0.3%, 0.4%, 0.5%, 0.7%, 0.8%, 0.9%, 1.0%, 1.5%, 2.0%, 3.0%, 4.0%, 5.0%, 6.0%, 7.0%, 8.0%, 9.0%, 10.0%, etc., preferably 0.2-5%, and any other specific point value within the above numerical range can be selected, so they will not be repeated here.

[0049] The collagen content in the shell spinning solution is specifically selected to be 0.2-5% by weight because increasing the concentration would increase the viscosity of the spinning solution, resulting in suboptimal spinning results and affecting the mechanical properties of the nanofiber membrane. Lowering the concentration would also affect the repair properties of the nanofiber membrane. The 0.2-5% concentration range is the optimal balance between these two.

[0050] Preferably, the concentration of ε-polylysine in the shell spinning solution is 0-10% but not including 0, for example 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., preferably 0.5-5%; any other specific point value within the above numerical range can be selected, and they will not be repeated here.

[0051] Preferably, the temperature of the coaxial spinning is 15-60°C, for example, 15°C, 20°C, 22°C, 25°C, 27°C, 30°C, 32°C, 35°C, 40°C, 50°C, 60°C, etc., and 20-35°C is further preferred. Any other specific point value within the above numerical range can be selected, and they will not be described here one by one.

[0052] Preferably, the humidity of the coaxial spinning is 25-80%, for example, 25%, 30%, 40%, 50%, 60%, 70% or 80%, etc., preferably 30-60%. Any other specific point value within the above numerical range can be selected, and they will not be described here one by one.

[0053] Preferably, the spinning voltage of the coaxial spinning is 5-28kV, such as 5kV, 8kV, 10kV, 12kV, 15kV, 18kV, 20kV, 22kV, 25kV or 28kV, etc., preferably 8-20kV. Any other specific point value within the above numerical range can be selected, and they will not be described here one by one.

[0054] Preferably, the distance between the coaxial spinning needle and the collector is 5-25 cm, for example, 5 cm, 8 cm, 10 cm, 15 cm, 20 cm or 25 cm, etc., preferably 8-15 cm. Any other specific point value within the above numerical range can be selected, and they will not be described here one by one.

[0055] Preferably, the flow rate of the core layer spinning solution in the coaxial spinning is 0.01-0.8 mL / h, for example, 0.01 mL / h, 0.02 mL / h, 0.05 mL / h, 0.1 mL / h, 0.2 mL / h, 0.3 mL / h, 0.4 mL / h, 0.5 mL / h, 0.6 mL / h or 0.8 mL / h, etc., more preferably 0.02-0.6 mL / h. Any other specific point value within the above numerical range can be selected, and they will not be repeated here.

[0056] Preferably, the flow rate of the shell spinning solution in the coaxial spinning is 0.01-1.5 mL / h, for example, 0.01 mL / h, 0.02 mL / h, 0.05 mL / h, 0.1 mL / h, 0.2 mL / h, 0.5 mL / h, 0.6 mL / h, 0.7 mL / h, 1.0 mL / h or 1.2 mL / h, etc., more preferably 0.02-1.2 mL / h. Any other specific point value within the above numerical range can be selected, and they will not be repeated here.

[0057] Preferably, the inner needle model of the coaxial needle used in the coaxial spinning is 20-23G, and the outer needle model is 15-18G.

[0058] Preferably, the soaking time is 5-60 min, for example, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min or 60 min, etc., preferably 10-30 min. Any other specific point value within the above numerical range can be selected, and they will not be described here one by one.

[0059] Preferably, the drying is natural drying, oven drying, vacuum drying or freeze drying, preferably vacuum freeze drying, and the time is 2-48h, for example, 2h, 3h, 4h, 10h, 15h, 20h or 48h, etc. Any other specific point value within the above numerical range can be selected, and they will not be repeated here.

[0060] Preferably, the spinning solution of step (2) or the water of step (4) contains ε-polylysine, and the concentration of ε-polylysine in the aqueous solution is 0-10% but not including 0, for example 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., preferably 0.2-5%. Any other specific point value within the above numerical range can be selected, and they will not be repeated here.

[0061] Preferably, the spinning solution of step (2) or the water of step (4) contains a material with anionic groups, and the concentration of the material with anionic groups in the aqueous solution is 0-10% but not including 0, for example 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., preferably 0.1-6%, and any other specific point value within the above numerical range can be selected, and they will not be repeated here.

[0062] Preferably, after the multifunctional medical material is prepared, it is further subjected to surface modification treatment to enhance or increase its function;

[0063] Preferably, the surface modification treatment may include but is not limited to cross-linking, plasma, and layer-by-layer self-assembly methods.

[0064] In yet another aspect, the present invention provides a drug delivery system, comprising a drug and the multifunctional medical material as described above as a drug carrier.

[0065] In another aspect, the present invention provides a method for preparing the drug delivery system as described above, the method comprising: adding a drug during the preparation of the shell spinning solution and / or the core spinning solution. When both the shell spinning solution and the core spinning solution contain drugs, the drugs may be of the same or different types.

[0066] The medical material of the present invention can also be used as a good drug carrier material, and the therapeutic effect can be optimized by adding different amounts and types of drugs to different spinning solution components.

[0067] Compared with the prior art, the present invention has the following beneficial effects:

[0068] The present invention forms a self-assembled spinning membrane by electrostatic spinning technology with ε-polylysine and collagen, materials with anionic groups, and poly-polymer materials to prepare a multifunctional medical material. The medical material has the advantages of both electrostatic spinning membrane and self-assembled membrane, and the production process is greatly simplified. The multifunctional medical material is close to the structure of the extracellular matrix and has a large specific surface area, which leads to an increase in its surface energy and activity, thereby producing a small size effect, a surface and interface effect, and can provide a large number of cell contact points, providing a better microenvironment for cell adhesion, proliferation, and physiological functions, and improving protein adsorption. The composition contains hydrophilic materials such as collagen, which can make the multifunctional medical material have good hydrophilicity. At the same time, its own good properties enable the product to be directly attached and used in clinical use, more effectively induce cell growth and tissue regeneration, and then effectively promote the repair of wound surface, significantly expanding its scope of application. The preparation method of the multifunctional medical material involved in the present invention is simple in process, easy to control product quality, and can achieve high-efficiency, low-pollution and low-cost industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 is a scanning electron microscope image of the multifunctional medical material prepared in Example 2;

[0070] Figure 2 is a scanning electron microscope image of the multifunctional medical material prepared in Example 2;

[0071] Figure 3 Schematic diagram of the contact angle of the multifunctional medical material prepared in Example 1;

[0072] Figure 4 1 is a graph showing the results of the inhibition zone test of the multifunctional medical material prepared in Example 1 (where a represents the result for Staphylococcus aureus and b represents the result for Escherichia coli);

[0073] Figure 5 1 is a graph showing the results of the inhibition zone test of the material prepared in Comparative Example 1 (where a represents the result for Staphylococcus aureus and b represents the result for Escherichia coli). DETAILED DESCRIPTION

[0074] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0075] Example 1

[0076] This embodiment provides a multifunctional medical material, and its preparation method is as follows:

[0077] (1) Dissolving type I collagen in hexafluoroisopropanol, and then slowly dissolving polylactic acid (PLA) with a weight average molecular weight of 112,000 in the collagen solution to obtain a uniform and stable solution after stirring at 25° C. to obtain a core layer spinning solution;

[0078] (2) Dissolving type I collagen in hexafluoroisopropanol, dissolving sodium alginate and ε-polylysine (molecular weight 4000) in acetone, mixing them, and then adding PLA to the solution. The mass percentage of PLA is 1%, the mass percentage of type I collagen is 1%, the concentration of sodium alginate is 1%, and the concentration of ε-polylysine is 0.5%, thereby obtaining a shell spinning solution;

[0079] (3) Coaxially spinning the shell layer spinning solution and the core layer spinning solution to prepare a coaxial nanofiber material; the electrospinning equipment is operated at 25° C. and a humidity of 40% for electrospinning, the core layer solution is advanced at a speed of 0.5 mL / h, the shell layer solution is advanced at a speed of 0.3 mL / h, the spinneret voltage is 16 kV, the spinning distance is 10 cm, the receiving device is a metal drum with a diameter of 10 cm, the rotation speed is 100 rpm, the inner needle model is 23G, and the outer needle model is 17G;

[0080] (4) The obtained coaxial nanofiber material was soaked in pure water for 20 minutes, and then dried in a freeze dryer for 4 hours to obtain the multifunctional medical material.

[0081] Example 2

[0082] This embodiment provides a multifunctional medical material, and its preparation method is as follows:

[0083] (1) Dissolving type I collagen in hexafluoroisopropanol, and then slowly dissolving polylactic acid (PLA) with a weight average molecular weight of 112,000 in the collagen solution to obtain a uniform and stable solution after stirring at 25° C. to obtain a core layer spinning solution;

[0084] (2) dissolving type I collagen in hexafluoroisopropanol, dissolving sodium alginate in acetone, mixing the two, and then adding PLA to the solution. The mass percentage of PLA is 1%, the mass percentage of type I collagen is 1%, and the concentration of sodium alginate is 1%, thereby obtaining a shell spinning solution.

[0085] (3) Coaxially spinning the shell layer spinning solution and the core layer spinning solution to prepare a coaxial nanofiber material; the electrospinning equipment is operated at 25° C. and a humidity of 40% for electrospinning, the core layer solution is advanced at a speed of 0.5 mL / h, the shell layer solution is advanced at a speed of 0.3 mL / h, the spinneret voltage is 16 kV, the spinning distance is 10 cm, the receiving device is a metal drum with a diameter of 10 cm, the rotation speed is 100 rpm, the inner needle model is 23G, and the outer needle model is 17G;

[0086] (4) The obtained coaxial nanofiber material was immersed in a 0.5% ε-polylysine (molecular weight 4500) aqueous solution for 20 minutes, then rinsed with pure water three times, and then dried in a freeze dryer for 4 hours to obtain the multifunctional medical material.

[0087] Example 3

[0088] This embodiment provides a multifunctional medical material, and its preparation method is as follows:

[0089] (1) Dissolving type I collagen in hexafluoroisopropanol, and then slowly dissolving poly(lactic acid-co-glycolic acid) (PLGA) with a weight average molecular weight of 120,000 in the collagen solution, wherein the mass percentage of PLGA is 10% and the mass percentage of type I collagen is 0.6%, and stirring at 25° C. to form a uniform and stable solution, thereby obtaining a core layer spinning solution;

[0090] (2) Dissolving type I collagen in hexafluoroisopropanol, dissolving sodium hyaluronate in formic acid, mixing the mixture, adding ε-polylysine (molecular weight 4000) to the solution and dissolving it, and then adding PLGA to the solution, wherein the mass percentage of PLGA is 2%, the mass percentage of type I collagen is 0.6%, the concentration of sodium hyaluronate is 0.5%, and the concentration of ε-polylysine is 1%, to obtain a shell spinning solution;

[0091] (3) Coaxially spinning the shell layer spinning solution and the core layer spinning solution to prepare a coaxial nanofiber material; the electrospinning equipment is operated at 25° C. and a humidity of 40% for electrospinning, the core layer solution is advanced at a speed of 0.2 mL / h, the shell layer solution is advanced at a speed of 0.1 mL / h, the spinneret voltage is 11 kV, the spinning distance is 10 cm, the receiving device is a metal drum with a diameter of 10 cm, the rotation speed is 100 rpm, the inner needle model is 23G, and the outer needle model is 17G;

[0092] (4) The obtained coaxial nanofiber material was soaked in pure water for 20 minutes, and then dried in a freeze dryer for 4 hours to obtain the multifunctional medical material.

[0093] Example 4

[0094] This embodiment provides a multifunctional medical material. The preparation method thereof differs from that of Example 1 only in that sodium alginate is replaced with sodium alginate and sodium hyaluronate in an equal mass ratio, i.e., the concentration of sodium alginate in the shell spinning solution is 0.5%, and the concentration of sodium hyaluronate is 0.5%. All other conditions remain unchanged.

[0095] Example 5

[0096] This embodiment provides a multifunctional medical material, the preparation method of which differs from that of Example 1 only in that sodium alginate is replaced with an equal amount of sodium hyaluronate, while other conditions remain unchanged.

[0097] Example 6

[0098] This embodiment provides a multifunctional medical material, the preparation method of which differs from that of Example 1 only in that the core layer spinning solution contains no type I collagen, while all other conditions remain unchanged.

[0099] Example 7

[0100] This example provides a multifunctional medical material. The preparation method differs from that of Example 1 only in that the PLA in the core layer spinning solution is replaced with PLA and PLGA in an equal weight ratio, i.e., the weight percentage of PLA is 4% and the weight percentage of PLGA is 4%; and the PLA in the shell layer spinning solution is replaced with PLA and PLGA in an equal weight ratio, i.e., the weight percentage of PLA is 0.5% and the weight percentage of PLGA is 0.5%. All other conditions remain unchanged.

[0101] Example 8

[0102] This example provides a multifunctional medical material. The preparation method differs from that of Example 1 only in that the PLA in the core layer spinning solution is replaced with an equal mass of PLGA, and the PLA in the shell layer spinning solution is replaced with an equal mass of PLGA. All other conditions remain unchanged.

[0103] Example 9

[0104] This embodiment provides a multifunctional medical material. The only difference between its preparation method and that of Example 3 is that the shell spinning solution does not contain sodium hyaluronate. After the nanofiber membrane is prepared, the pure water used for soaking is replaced by an aqueous solution of 0.5% sodium hyaluronate. Other conditions remain unchanged.

[0105] Example 10

[0106] This embodiment provides a multifunctional medical material, the preparation method of which is to perform surface modification treatment on the nanofiber membrane prepared in Example 9, that is, to perform layer-by-layer self-assembly on the nanofiber membrane:

[0107] (1) The nanofiber membrane was first soaked in a 0.6% ε-polylysine aqueous solution for 10 min, then rinsed in pure water three times and drained;

[0108] (2) Soaking the fiber nanomembrane in a 0.2% sodium hyaluronate aqueous solution for 10 min, then rinsing it in pure water three times and draining the water;

[0109] (3) Repeat steps (1) to (2) three times, and then dry in a vacuum freeze dryer for 4 hours to obtain the multifunctional medical material.

[0110] Example 11

[0111] This embodiment provides a drug delivery system, the preparation method of which differs from that of Example 3 only in that docetaxel (final concentration of 1%) is added to the shell layer spinning solution, and paclitaxel (final concentration of 1%) is added to the core layer spinning solution. After spinning, the system is freeze-dried directly without being immersed in water, and other conditions remain unchanged.

[0112] Comparative Example 1

[0113] This comparative example provides a medical material, the preparation method of which differs from that of Example 1 only in that the shell spinning solution does not contain ε-polylysine, and other components and contents remain unchanged, as do other conditions.

[0114] Comparative Example 2

[0115] This comparative example provides a medical material, the preparation method of which differs from that of Example 1 only in that neither the core layer spinning solution nor the shell layer spinning solution contains type I collagen, and other components and contents remain unchanged, as do other conditions.

[0116] Comparative Example 3

[0117] This comparative example provides a medical material, the preparation method of which differs from that of Example 1 only in that the shell spinning solution does not contain sodium alginate, and other components and contents remain unchanged, as do other conditions.

[0118] Comparative Example 4

[0119] This comparative example provides a medical material, and its preparation method is as follows:

[0120] (1) Polylactic acid (PLA) with a weight average molecular weight of 112,000 was dissolved in acetone at a concentration of 8%. After stirring at 25°C, a uniform and stable solution was formed for electrospinning. The electrospinning equipment was operated at 25°C and a humidity of 40%. The solution propulsion speed was 0.8 mL / h, the spinneret voltage was 13 kV, the spinning distance was 10 cm, the receiving device was a metal drum with a diameter of 10 cm, the rotation speed was 100 rpm, and the needle model was 22G to prepare PLA nanofiber membrane;

[0121] (2) The nanofibers prepared above were immersed in pure water for 20 minutes, and then dried in a freeze dryer for 4 hours.

[0122] Evaluation test:

[0123] (1) The multifunctional medical material prepared in Example 2 was observed by scanning electron microscopy. Figure 1 and Figure 2 As shown ( Figure 1 and Figure 2 (Figures represent fields of view at different magnifications). It can be seen from the figure that the nanofiber membrane presents an irregular spinning and weaving structure with uniform spinning morphology, dense interweaving, and uniform pores, which is very similar to the structure of the extracellular matrix.

[0124] (2) The multifunctional medical material prepared in Example 1 was subjected to a contact angle test. The specific operation was as follows: cut off 3cm*3cm of the nanofiber membrane, and place the nanofiber membrane on the sample table of the instrument to ensure that the sample is placed flat without wrinkles and distortions. Hang a 2μL water droplet at the end of the needle, raise the sample table so that the sample surface contacts the hanging water droplet, and then remove the sample to complete the transfer of the water droplet. During this process, the water droplet should not fall or spray out of the sample surface. Adjust the contact baseline between the water droplet and the sample surface, and automatically analyze it through computer software. In the case of passing, the contact angle is measured within (60±10)s after the water droplet is transferred, and the sample is moved so that the next drop of water falls on the new test part of the sample. The results are as follows Figure 3 As shown in the figure, it can be seen that the nanofiber membrane under this condition has good hydrophilicity.

[0125] (3) Antibacterial evaluation

[0126] The products obtained in Examples 1-11 and Comparative Examples 1-4 were cut into samples with a diameter of 17 mm. They were placed in a tryptic soy agar culture dish coated with Staphylococcus aureus and Escherichia coli and inverted for 24 h at 35°C. The size of the inhibition zone was observed and calculated (three tests were conducted in parallel for each group), as shown in Table 1 (data are presented as average values). The antibacterial results of Example 1 and Comparative Example 4 are shown in Table 1. Figure 4 and Figure 5 As shown (where a represents the result for Staphylococcus aureus and b represents the result for Escherichia coli).

[0127] Table 1

[0128]

[0129]

[0130] From the data in Table 1, we can see that:

[0131] When the multifunctional medical material lacked ε-polylysine, no inhibition zone was produced. However, all multifunctional medical materials containing ε-polylysine exhibited an inhibition zone. This indicates that the antibacterial effect of the multifunctional medical material is produced by the release of ε-polylysine, and that natural polymer materials, collagen, and sodium alginate themselves do not inhibit Escherichia coli and Staphylococcus aureus.

[0132] (4) In vitro cytotoxicity test

[0133] The multifunctional medical materials obtained in Examples 1-11 and Comparative Examples 1-4 were irradiated and sterilized, and then immersed in DMEM complete medium to prepare material extracts. The specific operation was as follows: 2cm*3cm multifunctional medical materials were cut and 6cm thick. 2 The extraction ratio was 100 μg / mL and the mixture was extracted at 37°C for 24 h. The cytotoxicity of the multifunctional medical material was evaluated by in vitro cytotoxicity test (MTT). Mouse fibroblast cell line (L929) was cultured at 1×10 5 Cells were seeded at a density of 10 cells / mL in a 96-well tissue culture plate. After 24 hours of standard culture, the culture medium was discarded and 100 μL of the multifunctional medical material extract was added and cultured for another 24 hours. A blank control group was incubated with untreated complete culture medium for 24 hours before an MTT assay. The absorbance at 570 nm was measured using a microplate reader, and the survival rate of L929 cells was determined through statistical analysis. The results are shown in Table 2.

[0134] Table 2

[0135]

[0136]

[0137] From the data in Table 2, we can see that:

[0138] The cell viability of the multifunctional medical materials in each group was >70%, demonstrating their excellent biocompatibility and lack of cytotoxicity. ε-polylysine, with its antibacterial properties, has some cytotoxicity, but the use of collagen and materials with anionic groups mitigates this cytotoxicity, ultimately contributing to the excellent biocompatibility of the multifunctional medical materials.

[0139] (5) Mechanical properties

[0140] The operation method is as follows: cut the fiber membranes of Examples 1-11 and Comparative Examples 1-4 with a length of 6 cm and a width of 1 cm; measure the thickness with a thickness gauge (measure three times and take the average value), and fill the measured data into the tensile testing machine software; adjust the spacing between the clamps of the tensile testing machine to 4 cm, install the nanofiber membrane on the clamp of the tensile testing machine, and make the upper and lower clamps respectively clamp one end of the nanofiber membrane to keep the fiber membrane vertical and flat, and then tighten the clamps; stretch at a rate of 10 mm / min until the fiber membrane breaks, and obtain the test results, as shown in Table 3.

[0141] Table 3

[0142]

[0143]

[0144] From the data in Table 3, we can see that:

[0145] The elongation at break, maximum tensile force, and tensile strength of a material directly affect its application. The elongation at break refers to the ratio of the displacement value of the material when it is broken to its original length, which is a characterization of the material's toughness; the maximum tensile force characterizes the material's maximum stress. Natural polymer materials can serve as biological scaffolds when their tensile strength reaches 1500KPa to play a supporting role. Therefore, the mechanical properties of the prepared multifunctional medical materials can meet the required mechanical strength.

[0146] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate a multifunctional medical material and its preparation method, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent replacements for various raw materials in the product of the present invention, addition of auxiliary ingredients, and selection of specific methods, etc., are all within the scope of protection and disclosure of the present invention.

[0147] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0148] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A multifunctional medical material, characterized in that: The multifunctional medical material is an electrospun fiber membrane prepared from materials including polymer materials, materials with anionic groups, collagen and ε-polylysine; The electrospinning adopts coaxial electrospinning technology, and the fibers in the electrospinning fiber membrane include a core layer structure and a shell layer structure; The raw materials for preparing the core layer structure include polymer materials and collagen; The raw materials for preparing the shell structure include polymer materials, materials with anionic groups, collagen and ε-polylysine; The material with anionic groups is a combination of sodium alginate and sodium hyaluronate.

2. The multifunctional medical material according to claim 1, wherein The raw materials for preparing the core layer structure include 5-15 parts of polymer material and 1-20 parts of collagen in parts by mass.

3. The multifunctional medical material according to claim 2, wherein: The raw materials for preparing the core layer structure include 8-12 parts of polymer material and 1-10 parts of collagen in parts by mass.

4. The multifunctional medical material according to claim 1, wherein The raw materials for preparing the shell structure include, by weight, 1-5 parts of a polymer material, 0.1-6 parts of a material with anionic groups, 0.2-3 parts of collagen, and 0.5-5 parts of epsilon-polylysine.

5. The multifunctional medical material according to claim 1, wherein The polymer material includes any one or a combination of at least two of polylactic acid, polyglycolide, polycaprolactone, polyvinyl alcohol, polylactic acid-glycolic acid copolymer, polyethylene glycol, polytetrafluoroethylene, polyester amide or polyurethane.

6. The multifunctional medical material according to claim 5, characterized in that The polymer material is a combination of polylactic acid and polylactic acid-glycolic acid copolymer.

7. The multifunctional medical material according to claim 1, wherein The collagen includes any one of type I collagen or its active domain, type II collagen or its active domain, type III collagen or its active domain, or a combination of at least two thereof.

8. The multifunctional medical material according to claim 7, wherein: The collagen is type I collagen or type III collagen.

9. The multifunctional medical material according to claim 1, wherein The molecular weight of the ε-polylysine is 3000-5000.

10. The multifunctional medical material according to claim 9, wherein The molecular weight of the ε-polylysine is 3600-4600.

11. The multifunctional medical material according to claim 10, wherein The molecular weight of the ε-polylysine is 3600-4300.

12. The method for preparing a multifunctional medical material according to any one of claims 1 to 11, characterized in that: The preparation method comprises the following steps: (1) Mixing and dissolving the polymer material with a solvent to obtain a core layer spinning solution; collagen is also dissolved in the core layer spinning solution; (2) dissolving the polymer material and collagen in a solvent respectively and then mixing them to obtain a shell spinning solution; (3) coaxially spinning the shell layer spinning solution and the core layer spinning solution to prepare the multifunctional medical material, optionally further comprising soaking the multifunctional medical material in water and then drying; The shell spinning solution of step (2) or the water of step (3) optionally contains ε-polylysine; the shell spinning solution of step (2) or the water of step (3) optionally contains a material with anionic groups; and the ε-polylysine and the material with anionic groups are not present in the water of step (3) at the same time; the material with anionic groups is a combination of sodium alginate and sodium hyaluronate.

13. The method for preparing the multifunctional medical material according to claim 12, wherein: The solvent is selected from chloroform, dichloromethane, N,N- Any one of dimethylformamide, methanol, ethanol, hexafluoroisopropanol, trifluoroacetonitrile, trifluoroacetic acid, formic acid, acetic acid or acetone, or a combination of at least two thereof.

14. The method for preparing the multifunctional medical material according to claim 12, wherein: The concentration of the polymer material in the core layer spinning solution is 5-15%.

15. The method for preparing the multifunctional medical material according to claim 14, wherein: The concentration of the polymer material in the core layer spinning solution is 8-12%.

16. The method for preparing the multifunctional medical material according to claim 12, wherein: The concentration of collagen in the core layer spinning solution is 0.5-5%.

17. The method for preparing the multifunctional medical material according to claim 16, wherein: The concentration of collagen in the core layer spinning solution is 0.5-3%.

18. The method for preparing the multifunctional medical material according to claim 12, wherein: The concentration of the polymer material in the shell spinning solution is 1-10%.

19. The method for preparing the multifunctional medical material according to claim 18, wherein: The concentration of the polymer material in the shell spinning solution is 1-5%.

20. The method for preparing the multifunctional medical material according to claim 12, wherein: The concentration of collagen in the shell spinning solution is 0.2-10%.

21. The method for preparing the multifunctional medical material according to claim 20, wherein: The concentration of collagen in the shell spinning solution is 0.2-5%.

22. The method for preparing the multifunctional medical material according to claim 12, wherein: The concentration of ε-polylysine in the shell spinning solution is 0-10%.

23. The method for preparing the multifunctional medical material according to claim 22, wherein: The concentration of ε-polylysine in the shell spinning solution is 0.5-5%.

24. The method for preparing the multifunctional medical material according to claim 12, wherein: The concentration of the material with anionic groups in the shell spinning solution is 0.1-6%.

25. The method for preparing the multifunctional medical material according to claim 12, wherein: The temperature of the coaxial spinning is 15-60°C.

26. The method for preparing the multifunctional medical material according to claim 25, wherein: The temperature of the coaxial spinning is 20-35°C.

27. The method for preparing the multifunctional medical material according to claim 12, wherein: The humidity of the coaxial spinning is 25-80%.

28. The method for preparing the multifunctional medical material according to claim 27, wherein: The humidity of the coaxial spinning is 30-60%.

29. The method for preparing the multifunctional medical material according to claim 12, wherein: The spinning voltage of the coaxial spinning is 5-28 kV.

30. The method for preparing the multifunctional medical material according to claim 29, wherein: The spinning voltage of the coaxial spinning is 8-20 kV.

31. The method for preparing the multifunctional medical material according to claim 12, wherein: The distance between the coaxial spinning needle and the collector is 5-25 cm.

32. The method for preparing the multifunctional medical material according to claim 31, wherein: The distance between the coaxial spinning needle and the collector is 8-15 cm.

33. The method for preparing the multifunctional medical material according to claim 12, wherein: The flow rate of the core layer spinning solution in the coaxial spinning is 0.01-0.8 mL / h.

34. The method for preparing the multifunctional medical material according to claim 33, wherein: The flow rate of the core layer spinning solution in the coaxial spinning is 0.02-0.6 mL / h.

35. The method for preparing the multifunctional medical material according to claim 12, wherein: The flow rate of the shell spinning solution in the coaxial spinning is 0.01-1.5 mL / h.

36. The method for preparing the multifunctional medical material according to claim 35, wherein: The flow rate of the shell spinning solution in the coaxial spinning is 0.02-1.2 mL / h.

37. The method for preparing the multifunctional medical material according to claim 12, wherein: The coaxial spinning uses a coaxial needle with an inner needle model of 20-23 G and an outer needle model of 15-18 G.

38. The method for preparing the multifunctional medical material according to claim 12, wherein: The soaking time is 5-60 min.

39. The method for preparing the multifunctional medical material according to claim 38, wherein: The soaking time is 10-30 min.

40. The method for preparing the multifunctional medical material according to claim 12, wherein: The drying is natural drying, oven drying or freeze drying.

41. The method for preparing the multifunctional medical material according to claim 12, wherein: The drying time is 2-48 h.

42. The method for preparing the multifunctional medical material according to claim 12, wherein: The prepared multifunctional medical material is subjected to surface modification treatment to enhance or increase its function.

43. The method for preparing the multifunctional medical material according to claim 42, wherein: The surface modification treatment includes cross-linking, plasma, and layer-by-layer self-assembly methods.

44. A drug delivery system, characterized in that The drug delivery system comprises a drug and the multifunctional medical material according to any one of claims 1 to 11 as a drug carrier.

45. The method for preparing the drug delivery system according to claim 44, wherein: The preparation method comprises: adding medicine during the process of preparing the shell layer spinning solution and / or the core layer spinning solution.

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