High-load antibacterial absorbable patch as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of biological materials, and particularly relates to a high-load antibacterial absorbable patch as well as a preparation method and application thereof. The patch comprises a nanofiber layer with an oriented structure and an antibacterial agent deposition layer adsorbed on the surface and in pores of the nanofiber layer, wherein the nanofiber layer is prepared from a mixed solution of biodegradable aliphatic polyester and an antibacterial agent through electrostatic spinning, and the mass ratio of the antibacterial agent to the biodegradable aliphatic polyester in the mixed solution is (1-2): 50; the biodegradable aliphatic polyester comprises long-chain aliphatic polyester and short-chain aliphatic polyester, and the mass ratio of the long-chain aliphatic polyester to the short-chain aliphatic polyester in the mixed solution is 1: (0.3-3). The patch provided by the invention has a three-dimensional porous structure for promoting cell adhesion and proliferation, good degradation matching property and mechanical supporting property, and high drug-loading property capable of realizing long-acting controlled release of antibacterial drugs, so that tissue repair is effectively promoted.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of biological materials, and particularly relates to a high-load antibacterial absorbable patch as well as a preparation method and application thereof. BACKGROUND

[0002] Biological patches are widely used in the repair of contaminated wounds due to their natural ability to resist infection, and have become the only choice for the repair of tissue defects with contamination or infection. However, this ability to resist infection mainly depends on early local rapid revascularization and phagocyte infiltration, thereby inhibiting the formation of bacterial biofilm, rather than having direct antimicrobial activity. Studies have shown that bacterial biofilm may still form on the surface of the implanted biological patch, and the collagenase secreted by the bacteria can cause rapid degradation of the patch structure. Therefore, biological patches still have a high failure rate when used to repair obviously contaminated or infected abdominal wall defects and rotator cuff tears, and the failed cases are often accompanied by surgical site infection.

[0003] Currently, the conventional treatment for such infections relies on systemic administration, but the use of long-term high-dose antibiotics not only makes it difficult to maintain an effective concentration at the infection site, but also may cause systemic toxicity and increase the burden on the liver and kidneys. Therefore, how to achieve local controlled release of drugs, maintain a stable antibacterial concentration in the deep part of the infected tissue, and avoid systemic side effects has become a key problem to be solved. In the future, the optimization direction of absorbable biological patches should focus on improving the synergistic effect of their anti-infection ability and tissue regeneration function to further improve their clinical success rate in complex infection environments. SUMMARY

[0004] TECHNICAL PROBLEM

[0005] The present application aims to provide a high-load antibacterial absorbable patch with a three-dimensional porous structure, good degradation performance, and the ability to provide support strength, high drug loading, long-term antibacterial effect, facilitate cell adhesion, proliferation, and tissue repair, and a simple preparation method.

[0006] TECHNICAL SCHEME

[0007] The high-load antibacterial absorbable patch provided by the first aspect of the application is characterized by comprising a nanofiber layer with an orientation structure and an antibacterial agent deposition layer adsorbed on the surface and pores of the nanofiber layer; wherein the nanofiber layer is made by electrospinning a mixed solution of biodegradable aliphatic polyester and antibacterial agent, the mass ratio of antibacterial agent to biodegradable aliphatic polyester in the mixed solution is 1-2:50; the biodegradable aliphatic polyester comprises long-chain aliphatic polyester and short-chain aliphatic polyester, and the mass ratio of long-chain aliphatic polyester to short-chain aliphatic polyester in the mixed solution is 1:0.3-3. Polycaprolactone (PCL) is a commonly used biomedical material, which can usually be used as an in-vivo implant material and a drug controlled-release material, has strong mechanical properties, and is easily soluble in many organic solvents, but PCL material has the disadvantages of low cell affinity and slow degradation rate; polyglycolide (PGA) has good biocompatibility and excellent mechanical properties, but is difficult to dissolve in organic solvents and has a relatively fast biodegradation rate; by blending PCL and PGA at a suitable ratio, the patch made by copolymerization has a suitable biodegradation rate and excellent biocompatibility and mechanical properties. In addition, the application does not introduce a crosslinking agent that may have adverse effects in addition to the necessary high molecular polymers for preparing the fiber layer, thereby avoiding the risk that the crosslinking agent may induce inflammation. Most importantly, the application additionally adds an antibacterial agent to the electrospinning solution, so that the degradation process of the patch is coupled with the release of the antibacterial agent, achieving a long-term drug release effect, ensuring an antibacterial environment during the overall healing period of the abdominal wall or rotator cuff, especially in the later healing stage, and at the same time, the patch realizes high-load drug loading by receiving the antibacterial agent released by the filter paper, thereby ensuring timely, immediate and sufficient supply of the antibacterial agent in the key stage of the early healing of the abdominal wall or rotator cuff.

[0008] In some embodiments, the mass ratio of long-chain aliphatic polyester to short-chain aliphatic polyester in the mixed solution is 1:1.

[0009] In some embodiments, the long-chain aliphatic polyester is polycaprolactone, and the short-chain aliphatic polyester is polyglycolide; the antibacterial agent is selected from one or more of triclosan, berberine, artemisinin, benzalkonium bromide, octenidine, domiphen, chlorhexidine, and preferably triclosan.

[0010] In some embodiments, the antibacterial agent deposition layer is formed by bonding the nanofiber layer with a carrier loaded with the antibacterial agent, and the nanofiber layer receives the antibacterial agent released by the carrier during sterilization.

[0011] In some embodiments, the high-load antibacterial absorbable patch has a porosity of 70%-90%, a pore tortuosity of less than 1.5, and a pore size of 0.8-2 μm; and the high-load antibacterial absorbable patch has a thickness of 0.1 mm-10 mm.

[0012] In some embodiments, the high-load antibacterial absorbable patch has a breaking strength retention value of 80% or more after 2 weeks, and a breaking strength retention value of 65% or more after 4 weeks; the high-load antibacterial absorbable patch has a mass loss rate of 3% or less after 2 weeks, and a mass loss rate of 13% or less after 4 weeks; and the high-load antibacterial absorbable patch has a drug loading amount of greater than 13 mg / g.

[0013] The second aspect of the present application provides the use of the high-load antibacterial absorbable patch in any of the above embodiments in the preparation of a material for repairing abdominal wall defects or rotator cuff tears. Both conditions belong to defects caused by interruption of tissue continuity or structural weakness, and a long repair process requires temporary support from external materials to promote tissue regeneration and remodeling.

[0014] The third aspect of the present application provides a preparation method of the high-load antibacterial absorbable patch in any of the above embodiments, which comprises the following steps: S1. preparing a mixed solution containing a long-chain aliphatic polyester, a short-chain aliphatic polyester, and an antibacterial agent; S2. electrospinning the mixed solution to prepare a nanofiber layer, and vacuum drying; S3. adhering the carrier loaded with the antibacterial agent to the fiber layer, heat-sealing with a paper-plastic bag, sterilizing with ethylene oxide, and obtaining the high-load antibacterial absorbable patch.

[0015] The fourth aspect of the present application provides a preparation method of the high-load antibacterial absorbable patch in any of the above embodiments, which comprises the following steps: S1. preparing a mixed solution containing polycaprolactone, polyglycolide, and triclosan; S2. electrospinning the mixed solution to prepare a nanofiber layer, and vacuum drying; S3. adhering the carrier loaded with the antibacterial agent to the fiber layer, heat-sealing with a paper-plastic bag, sterilizing with ethylene oxide, and obtaining the high-load antibacterial absorbable patch.

[0016] In some embodiments, the specific configuration step of the mixed solution in S1 is: dissolving polycaprolactone and polyglycolide in at least one of hexafluoroisopropanol, trifluoroethanol, trichloromethane, dichloromethane, methanol, or N,N'-dimethylformamide to obtain a degradable aliphatic polyester solution, dissolving triclosan in at least one of ethyl acetate, diethyl ether, ethanol, or acetone to obtain an antibacterial agent solution, and finally mixing the two.

[0017] In some embodiments, polycaprolactone and polyglycolide are dissolved in hexafluoroisopropanol; and triclosan is dissolved in ethyl acetate.

[0018] In some embodiments, the mass percentage concentration of polycaprolactone + polyglycolide in the degradable aliphatic polyester solution is 8-12%, and the mass percentage concentration of triclosan in the antibacterial agent solution is 8-12%.

[0019] In some embodiments, in the electrospinning in the S2 step, the flow rate of the single propelling pump for the spinning solution is 1.8-3.0 mL / h, the working voltage is 20-30 kV, the distance between the injector needle and the receiver is 12-18 cm, and the rotation speed of the receiver is 1300-3000 r / min; the vacuum drying time in the S2 step is 12-18 h, and the temperature is 35-38℃. The relative positions of the fibers prepared by the method of the application present regularity, and the fibers have good tensile resistance, avoiding random winding, crossing or stacking in a disordered state, and the overall structure is more regular.

[0020] In some embodiments, the receiver is an aluminum foil receiver or a tin paper receiver, and the receiver is a roller with a diameter of 10-15 cm; the model of the injector needle is a blunt needle with a diameter of 20G, 22G or 24G.

[0021] In some embodiments, the carrier is a Tyvek paper, and the specific steps for loading the antibacterial agent on the carrier in the S3 step are as follows: after cutting the Tyvek paper, the Tyvek paper is soaked in an ethyl acetate solution containing 0.5-1.5% triclosan by weight for 0.5-1 h, and then vacuum dried at 35-38℃ for 3-5 h to volatilize the ethyl acetate, and finally the dried Tyvek paper is attached to the nanofiber layer with the same size as the cut Tyvek paper.

[0022] In some embodiments, the conditions for the ethylene oxide sterilization in the S3 step are as follows: nitrogen filling, temperature 50-80℃, vacuum rate 10-30 kpa / min, and vacuum pressure -90 to -50 kpa. During the sterilization, the antibacterial agent loaded on the carrier is released to the surface and pores of the nanofiber layer by a chemical vapor deposition method, and a deposition layer of the antibacterial agent is formed.

[0023] The fifth aspect of the application provides an abdominal wall defect or rotator cuff tear repair material product, which comprises an aluminum foil bag and a Tyvek paper packaged in a paper-plastic bag and a high-load antibacterial absorbable patch as described above.

[0024] Technical effects

[0025] 1. The patch of the application is prepared by a solution electrospinning method, and the composite patch prepared by the method has a three-dimensional porous structure, which is beneficial to the adhesion and proliferation of cells, thereby reducing the pain and discomfort of patients and accelerating the repair of normal tissues.

[0026] 2. The patch provided by the application has good degradation performance, and the breaking strength retention value after 4 weeks is more than 60%, and the mass loss rate is less than 13%, so it can meet the needs of providing good support strength during the healing process of tissues.

[0027] 3. The patch provided by the present application not only carries a high dose of antibacterial drugs by receiving the antibacterial agents released by the Tyvek paper, but also contains antibacterial drugs in the fiber structure of the patch itself, so that the patch continuously releases antibacterial drugs during degradation, providing long-term antibacterial performance during tissue healing, creating a stable environment for tissue regeneration, and further promoting healing.

[0028] 4. Compared with the double-layer or multi-layer complex structure of the biological patch on the market, the patch of the present application is a single-layer structure, which is more light and more suitable for the tissue defect site, thereby reducing the foreign body sensation, and the drug loading is more direct and convenient, and the overall preparation process is simplified. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 Process flow chart for high-load antibacterial patch;

[0030] Figure 2 Scanning electron microscope (SEM) image for micro-morphology test;

[0031] Figure 3 Infrared spectrum of high-load antibacterial absorbable patch;

[0032] Figure 4 Liquid chromatogram of triclosan standard solution;

[0033] Figure 5A In vitro breaking strength retention value change trend of high-load antibacterial absorbable patch;

[0034] Figure 5B In vitro mass loss rate change trend of high-load antibacterial absorbable patch;

[0035] Figure 6 Microscope images of absorbable patch at 1, 3, and 7 days, with a scale of 200 μm;

[0036] Figure 7 Antibacterial test chart of high-load absorbable patch on different bacteria. DETAILED DESCRIPTION

[0037] In order to facilitate the technical solutions of the application, the following first generally explains and defines the terms and phrases related to the present application.

[0038] The terms "comprise", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the recited element.

[0039] Oriented fiber patch refers to a nanofiber patch prepared by an electrospinning process, in which the fibers have a specific arrangement direction.

[0040] In each group of experiments provided in the present application, unless otherwise specified, the experimental conditions, materials, etc. remain the same except for the differences indicated in each group, so as to have comparability.

[0041] The reagents and instruments used in the embodiments of the present application, unless otherwise specified, can be purchased from the market.

[0042] The following further describes a high-load antibacterial absorbable patch, a preparation method and application thereof.

[0043] Example 1: Preparation of high-load antibacterial absorbable patch

[0044] Step one: preparation of antibacterial electrospinning solution

[0045] 20g of PCL (polycaprolactone, Mn50000-80000) and 20g of PGA (polyglycolide) were weighed with an electronic balance and added to 360g of hexafluoroisopropanol solution. Under magnetic stirring, the PCL+PGA was completely dissolved in the hexafluoroisopropanol solution (purity above 95%) for 6h to prepare a PCL+PGA solution with a mass ratio of 10%; 1g of triclosan was dissolved in 9g of ethyl acetate to prepare a triclosan-ethyl acetate solution with a mass ratio of 10%, which was then added to the PCL+PGA solution with a mass ratio of 10% to form a mixed electrospinning initial solution containing the drug.

[0046] Step two: preparation of fiber layer

[0047] The 100 mL 10% drug-containing mixed electrospinning initial solution prepared in Example 1 was transferred to a syringe in a fume hood, and a blunt needle with a 24G type was installed on the syringe. The syringe was installed on the electrospinning machine, and the pump was pushed at a rate of 2 mL / h. The distance between the needle tip and the receiver was 12-18 cm. The needle end was connected to a positive high voltage, and the receiver end was connected to a negative high voltage, with a voltage difference of 20-30 kV. On the receiver (a roller with a diameter of 10-15 cm) rotating at a high speed of 1500 r / min, an aluminum foil / tin paper was used to receive the nanofibers. After electrospinning, the nanofiber was taken out together with the tin paper and treated in a vacuum drying oven for 12-18 h, with a vacuum drying temperature of 37°C, to fully volatilize the hexafluoroisopropanol and ethyl acetate, and obtain a nanofiber layer with an oriented structure (thickness of 0.1-10 mm), which was then packaged and sealed with an aluminum foil bag for storage.

[0048] Step three: preparation of the whole patch

[0049] The electrospun fiber layer was cut into a shape of 100 mm x 60 mm (length x width), 2 g of triclosan (purity above 99%) was dissolved in 200 g of ethyl acetate (purity above 99%) to prepare a 1% triclosan-ethyl acetate solution. A knife die was used to cut the Tyvek paper (manufacturer: Shanghai Puma; model: 1073B) into a shape of 100 mm x 60 mm, and then the Tyvek paper was soaked in the prepared 1% triclosan-ethyl acetate solution for 0.5-1 h, and vacuum dried at a temperature of 37°C for 4 h to fully volatilize the ethyl acetate. Finally, the cut fiber layer was attached to the soaked and dried Tyvek paper, and the paper was heat-sealed in a paper-plastic bag, sterilized by ethylene oxide (nitrogen filling, temperature 50-80°C, vacuum rate 10-30 kpa / min, vacuum pressure -90 to -50 kpa), and packaged and heat-sealed in an aluminum foil bag. The preparation process of the whole patch is shown in Figure 1 .

[0050] Example 2: Preparation of high-load antibacterial absorbable patch

[0051] The difference from Example 1 is that 10 g of PCL and 30 g of PGA were weighed on an electronic balance and added to 360 g of hexafluoroisopropanol solution; 1 g of triclosan was dissolved in 9 g of ethanol.

[0052] Example 3: Preparation of high-load antibacterial absorbable patch

[0053] The difference from Example 1 is that 30 g of PCL and 10 g of PGA were weighed on an electronic balance and added to 360 g of dichloromethane solution; 1 g of a mixture of berberine and artemisinin was dissolved in 9 g of acetone.

[0054] Test Example 1: Physicochemical characterization of the patch

[0055] 1. Microstructure test

[0056] The patch was observed by scanning electron microscope, as shown in FIGS. A and B, which are microstructures at different magnifications, and the nanofiber layer can be seen in FIG. B. The composite patch prepared by the present application has a three-dimensional porous structure, which is conducive to cell adhesion and proliferation. Figure 2 2. Porosity test

[0057] The porosity (M) was tested by the immersion method. The sample was immersed in anhydrous ethanol for 24 h, and the mass of the sample before and after immersion was measured, and the porosity was calculated according to the following formula:

[0058]

[0059] Wherein, J1 is the mass of the sample after immersion, J2 is the mass of the sample before immersion, p is the density of anhydrous ethanol, and V is the apparent volume of the sample.

[0060] 3. Infrared analysis

[0061] The functional groups present in the electrospun film were determined according to the infrared wavelength corresponding to the absorption peak tested by Fourier infrared spectroscopy, so as to determine the components in the patch. As shown in FIG. 4, the patch of the present application was tested to have components of PCL+PGA.

[0062] Figure 3 4. Antibacterial drug content test

[0063] The content of triclosan in the high-load antibacterial absorbable patch was detected by high performance liquid chromatography (HPLC). The standard working solution was plotted with triclosan concentration as the abscissa and peak area as the ordinate to draw the standard working curve. The liquid chromatogram of the triclosan standard solution is shown in FIG. 5.

[0064] The peak area (or peak height) of the triclosan chromatographic peak after each standard solution was recorded, and the average value of the peak area (or peak height) of each concentration point was calculated, so that the content of triclosan in the patch was tested to be 13.625 mg / g, indicating that the patch provided by the present application has high drug loading capacity. Figure 4

[0065] Test Example 2 Performance test of patch

[0066] 1. In vitro degradation performance

[0067] 1. In vitro degradation performance

[0068] ​​The high-load antibacterial absorbable patch selected in this study was immersed in PBS buffer at 37°C for 0, 1, 2, and 4 weeks for degradation. Phosphate buffer solution with a pH of 7.4 was used as the in vitro degradation solution. Since the pH of the human body is between 7.35 and 7.45, the pH of the buffer solution was monitored weekly. If the pH was outside the range of 7.35-7.45, the buffer solution was replaced. The sample was immersed in PBS buffer at 37°C. After the specified time points, the sample and degradation solution were separated. The sample was used for tensile strength and mass loss testing.

[0069] 1) Fracture strength test

[0070] Samples were taken out at different time points and surface moisture was removed. The high-load antibacterial absorbable patch was cut into 60mm×20mm pieces, and both ends were fixed to the clamps of a tensile testing machine. The suture was pulled apart at a speed of 100mm / min±10mm / min, and the maximum force value was recorded. The breaking strength was measured, and the breaking strength retention value was calculated according to Formula 1.

[0071]

[0072] in:

[0073] X: Tensile strength retention value of the suture in the i-th week of degradation, %;

[0074] Fi: The breaking strength of the suture at week i, in N;

[0075] F0: Tensile strength of the suture, in N;

[0076] like Figure 5A As shown, the high-load antibacterial absorbable patch manufactured by the process of this invention retains 65% of its strength after four weeks. This means that during the critical stage of tissue healing (abdominal wall and rotator cuff healing usually takes several weeks to months), the patch has long-term anti-deformation properties in the moist environment of the defect site, and can provide sufficient mechanical support to avoid repair failure caused by tension at the defect site.

[0077] 2) Mass loss test

[0078] Before the experiment began, the mass of each degradation product was weighed and recorded as m. i1 At each degradation point, the sample was removed from the thermostatic shaker and dried under reduced pressure at 25°C to a constant weight using a filter (mass m). i2 After filtration, the degraded sample was rinsed five times with ultrapure water, and then placed together with the filter in a 25°C vacuum drying oven to constant weight. The weight after constant weight was measured as m. i3 Calculate the mass loss (%) according to formula (2).

[0079]

[0080] wherein:

[0081] W: mass loss of the product at the i-th time point, %;

[0082] m i1 : initial mass of the product;

[0083] m i2 : constant mass of the sand core funnel;

[0084] m i3 : sample dried to constant mass at the i-th time point.

[0085] As Figure 5B shown, the high-load antibacterial absorbable patch made by the process of the present application still retains more than 87% of the mass after four weeks, which means that the patch does not significantly degrade during the critical stage of tissue healing (the healing of abdominal wall and rotator cuff usually takes weeks to months), and as the tissue at the defect site gradually heals, the patch gradually degrades, and its degradation products can be absorbed by the body, without interfering with the later tissue remodeling.

[0086] 2. Biocompatibility (cell activity) test

[0087] In this study, vascular endothelial cells were used as a model and were normally frozen in a liquid nitrogen tank. After cell recovery, they were transplanted from the frozen tube to the culture bottle and placed in the incubator for culture, with a carbon dioxide concentration of 5%, a temperature of 37°C, and a humidity of 99%. The cell culture solution was prepared in a ratio of 89:10:1 from DMEM medium, fetal bovine serum (FBS), and 1% penicillin / streptomycin (double-antibiotic P&S). The culture medium was changed every two days, and when the cells grew to 80%-90% of the bottom of the culture bottle, they were subcultured. The biocompatibility of the high-load absorbable patch was verified by cell adhesion and proliferation behavior.

[0088] Cell adhesion: cells were stained by immunofluorescence, and cell morphology was observed under an inverted microscope. As Figure 6 shown, the high-load absorbable patch showed a higher degree of spreading, and as the culture time was prolonged, the cells proliferated rapidly, showing good cell activity.

[0089] 3. Antibacterial test

[0090] The triclosan in the high-load absorbable patch can inhibit the colonization of Staphylococcus aureus (SA), Staphylococcus epidermidis (SE), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE), Escherichia coli (EC) and Klebsiella pneumoniae (KP) on the absorbable patch. The antibacterial ring is measured by a vernier caliper. If the measured sample has an antibacterial zone of not less than 1.0 mm and a single measurement value of not less than 0.5 mm, the antibacterial effect is qualified. Figure 7 It can be seen that the minimum antibacterial ring diameter is also greater than 5 mm, indicating that the high-load absorbable patch provided by the application has good antibacterial effect.

[0091] The above specific embodiments further illustrate the purposes, technical solutions and beneficial effects of the application. It should be understood that the above is only a specific embodiment of the application and is not used to limit the protection scope of the application. Any modification, equivalent replacement, improvement, etc. made on the basis of the technical solutions of the application should be included in the protection scope of the application.

Claims

1. A high-load antibacterial absorbable patch, characterized in that, The invention comprises an oriented nanofiber layer and an antibacterial agent deposited on the surface and in the pores of the nanofiber layer; wherein the nanofiber layer is prepared by electrospinning a mixed solution of biodegradable aliphatic polyester and antibacterial agent, wherein the mass ratio of antibacterial agent to biodegradable aliphatic polyester in the mixed solution is 1-2:50; the biodegradable aliphatic polyester includes long-chain aliphatic polyester and short-chain aliphatic polyester, wherein the mass ratio of long-chain aliphatic polyester to short-chain aliphatic polyester in the mixed solution is 1:0.3-3.

2. The high-load antibacterial absorbable patch according to claim 1, characterized in that, The long-chain aliphatic polyester is polycaprolactone, and the short-chain aliphatic polyester is polyglycolic acid; the antibacterial agent is selected from one or more of triclosan, berberine, artemisinin, benzalkonium bromide, ostinidine, domiphen, and chlorhexidine.

3. The high-load antibacterial absorbable patch according to claim 1, characterized in that, The antimicrobial agent deposition layer is formed by attaching a nanofiber layer to a carrier loaded with antimicrobial agent, wherein the nanofiber layer receives the antimicrobial agent released by the carrier during sterilization.

4. The high-load antibacterial absorbable patch according to claim 1, characterized in that, The high-load antibacterial absorbable patch has a porosity of 70%–90%, a pore tortuosity of less than 1.5, a pore size of 0.8–2 μm, and a fiber diameter of 0.2–5 μm; the thickness of the high-load antibacterial absorbable patch is 0.1 mm–10 mm.

5. The high-load antibacterial absorbable patch according to claim 1, characterized in that, The high-load antibacterial absorbable patch retains a tensile strength of over 80% after 2 weeks and over 65% after 4 weeks; the mass loss rate of the high-load antibacterial absorbable patch is less than 3% after 2 weeks and less than 13% after 4 weeks; the drug loading of the high-load antibacterial absorbable patch is greater than 13 mg / g.

6. The use of the high-load antibacterial absorbable patch according to any one of claims 1-5 in the preparation of materials for repairing abdominal wall defects or rotator cuff tears.

7. The method for preparing the high-load antibacterial absorbable patch according to any one of claims 2-5, characterized in that, The method includes the following steps: S1. Prepare a mixed solution containing polycaprolactone, polyglycolic acid, and triclosan; S2. Electrospin the mixed solution to prepare a nanofiber layer, and then vacuum dry it; S3. After loading the antibacterial agent onto the carrier, it is bonded to the nanofiber layer, heat-sealed using a paper-plastic bag, and sterilized with ethylene oxide to obtain the high-load antibacterial absorbable patch.

8. The preparation method according to claim 7, characterized in that, The specific preparation steps of the mixed solution in step S1 are as follows: Polycaprolactone and polyglycolic acid are dissolved in at least one solvent selected from hexafluoroisopropanol, trifluoroethanol, chloroform, dichloromethane, methanol, or N,N'-dimethylformamide to obtain a biodegradable aliphatic polyester solution; then, triclosan is dissolved in at least one solvent selected from ethyl acetate, diethyl ether, ethanol, or acetone to obtain an antibacterial agent solution; finally, the two are mixed; wherein, the mass percentage concentration of polycaprolactone + polyglycolic acid in the biodegradable aliphatic polyester solution is 8-12%, and the mass percentage concentration of triclosan in the antibacterial agent solution is 8-12%.

9. The preparation method according to claim 7, characterized in that, In step S2, during electrospinning, the flow rate of the spinning solution in a single propulsion pump is 1.8–3.0 mL / h, the operating voltage is 20–30 kV, the distance between the syringe needle and the receiver is 12–18 cm, and the receiver rotation speed is 1300–3000 r / min; the vacuum drying time in step S2 is 12–18 h, and the temperature is 35–38 °C.

10. The preparation method according to claim 9, characterized in that, The receiver is an aluminum foil receiver or a tin foil receiver, and the receiver is a roller with a diameter of 10-15cm; the syringe needle is a blunt needle of type 20G, 22G, or 24G.

11. The preparation method according to claim 7, characterized in that, The carrier is Tyvek paper. The specific steps for loading the antibacterial agent onto the carrier in step S3 are as follows: after cutting the Tyvek paper, it is soaked in an ethyl acetate solution with a triclosan weight ratio of 0.5-5% for 0.5-1h, and then vacuum dried at 35-38℃ for 3-5h to allow the ethyl acetate to evaporate. Finally, the dried Tyvek paper is bonded to the cut nanofiber layer of the same size.

12. The preparation method according to claim 7, characterized in that, The specific conditions for ethylene oxide sterilization in step S3 are: nitrogen filling, temperature 50-80℃, vacuum rate 10-30 kPa / min, and vacuum pressure -90 to -50 kPa.

13. A material product for repairing abdominal wall defects or rotator cuff tears, characterized in that, The product includes aluminum foil bags and Tyvek paper sealed in aluminum foil bags and packaged in paper-plastic bags, and the high-load antibacterial absorbable patch as described in any one of claims 1-5.

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