Antibacterial film with ta / peg micro-nanofiber and preparation method thereof

Abstract

The application discloses an antibacterial film with TA / PEG micro-nanofiber and a preparation method thereof. The antibacterial film is composed of a macromolecular film and TA / PEG micro-nanofiber. The macromolecular film is composed of natural biological macromolecules and polyethylene glycol. The natural biological macromolecules include silk fibroin, collagen, sodium hyaluronate or gelatin. The TA / PEG micro-nanofiber is composed of tannic acid and polyethylene glycol. The TA / PEG micro-nanofiber is prepared by electrospinning and is adsorbed on the surface of the macromolecular film, so that a layer of TA / PEG micro-nanofiber film is uniformly covered on the surface of the macromolecular film. The antibacterial film is applied to the skin surface, has good adhesion to the skin surface, can quickly bond the tissues around a wound, has a strong inhibitory effect on the growth of staphylococcus aureus and escherichia coli, and achieves the purpose of repairing skin damage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical materials, in particular to an antibacterial film with TA / PEG micro-nano fibers and a preparation method thereof. BACKGROUND

[0002] Tannic acid, as a natural polyphenol compound, is widely present in plants. Due to its good biocompatibility and environmental friendliness, it has been applied in many fields. In recent years, tannic acid has attracted widespread attention due to its significant antibacterial performance. Tannic acid can inhibit the growth and reproduction of microorganisms by destroying their cell walls and membranes and changing their permeability. Especially for gram-positive bacteria, tannic acid shows stronger antibacterial effect, which is mainly due to the simple structure of the cell wall of gram-positive bacteria, which is easily destroyed by tannic acid.

[0003] Although tannic acid has excellent antibacterial performance, it also has some limitations in practical application, such as poor stability in water, easy to undergo oxidative polymerization reaction, resulting in a decrease in its antibacterial effect. In addition, when tannic acid is directly applied to the surface of materials, its adhesion is not strong enough to maintain the antibacterial effect for a long time. Therefore, developing a technology that can improve the stability and adhesion of tannic acid has become a research focus.

[0004] In order to overcome the above problems, researchers try to combine tannic acid with other materials, or make it into a coating, film material and other forms, in order to enhance its physical and chemical stability, and improve its durability in specific applications. For example, by combining tannic acid with polyvinyl alcohol (PVA), chitosan (Chitosan) and other high molecular materials, a composite film with excellent antibacterial performance can be formed. This kind of film not only improves the stability of tannic acid, but also enhances its adhesion on the contact surface, thus showing great application potential in the fields of medical equipment, food packaging, building surface treatment, etc.

[0005] However, the existing tannic acid antibacterial film products on the market still have certain limitations, such as complex preparation process, high cost, and unsatisfactory antibacterial effect. Therefore, the present application aims to provide a new preparation method of tannic acid antibacterial film, which can simplify the preparation process, reduce the cost, and improve the bacteriostatic rate and stability of tannic acid antibacterial film. SUMMARY

[0006] The present application aims to provide an antibacterial film with TA / PEG micro-nano fibers and a preparation method thereof to overcome the deficiencies in the prior art.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] The application discloses a preparation method of an antibacterial film with TA / PEG micro-nanofiber, and specifically comprises the following steps.

[0009] S1, a natural biological macromolecule and polyethylene glycol are taken and dissolved in purified water respectively to obtain a natural biological macromolecule aqueous solution and a polyethylene glycol aqueous solution; the natural biological macromolecule aqueous solution and the polyethylene glycol aqueous solution are uniformly mixed to obtain a mixed solution; the natural biological macromolecule is selected from one of silk fibroin, collagen, sodium hyaluronate and gelatin;

[0010] S2, the mixed solution obtained in step S1 is poured into a mold and dried, and is irradiated by an ultraviolet lamp to obtain a macromolecular film.

[0011] S3, tannic acid and polyethylene glycol are taken and dissolved in an alcohol solution respectively to obtain a tannic acid alcohol solution and a polyethylene glycol alcohol solution; the tannic acid alcohol solution and the polyethylene glycol alcohol solution are uniformly mixed to obtain a TA / PEG alcohol solution.

[0012] S4, the TA / PEG alcohol solution obtained in step S3 is subjected to spinning treatment together with the macromolecular film obtained in step S2.

[0013] S5, the macromolecular film after the spinning treatment is taken out and soaked in purified water, and finally taken out and dried to obtain an antibacterial film.

[0014] Preferably, in steps S1 and S3, the polyethylene glycol is polyethylene glycol 2000.

[0015] Preferably, in step S1, the mass ratio of the natural biological macromolecule to the polyethylene glycol is 9:1 to 7:3.

[0016] Preferably, in step S2, the drying temperature is 32-42 DEG C; the wavelength of the ultraviolet light is 254 nm, and the irradiation time is 1.5-2.5 h.

[0017] Preferably, in step S3, the mass concentration of the tannic acid is 5%-25%, and the mass concentration of the polyethylene glycol is 2%-10%; the alcohol solution is an ethanol aqueous solution with an ethanol volume concentration of 50%-95%.

[0018] Preferably, in step S3, the mass ratio of the solutes in the tannic acid alcohol solution and the polyethylene glycol alcohol solution is 1.5:1 to 2:1.

[0019] Preferably, in step S4, the TA / PEG alcohol solution obtained in step S3 is poured into a syringe of an electrostatic spinning machine, and the macromolecular film obtained in step S2 is fixed on a collector to perform spinning; the diameter of the micro-nanofiber obtained by electrostatic spinning of the TA / PEG alcohol solution is 50-100 nm.

[0020] Preferably, the soaking time in step S5 is 25-35 min, and the drying temperature is 32-42 DEG C.

[0021] The application further discloses an antibacterial film with TA / PEG micro-nano fibers, which is prepared by the preparation method of the antibacterial film with TA / PEG micro-nano fibers.

[0022] The application has the following beneficial effects:

[0023] 1. The macromolecular film is prepared by the solvent volatilization one-step method and ultraviolet crosslinking, and has good mechanical properties and is not easy to dissolve in water.

[0024] 2. The TA / PEG micro-nano fibers prepared by the electrospinning technology have a diameter of 50-100 nm and can be uniformly adsorbed on the surface of the macromolecular film.

[0025] 3. The antibacterial film is applied to the skin surface and has a strong inhibitory effect on the growth of Staphylococcus aureus and Escherichia coli.

[0026] 4. The antibacterial film has good adhesion to the skin surface, can quickly bond the tissues around a wound and effectively repair skin damage.

[0027] The features and advantages of the application will be described in detail with reference to the embodiments and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 Fig. 6 is a diagram showing the change of the breaking strength and breaking elongation of the SF / PEG macromolecular film with the increase of the PEG molecular weight;

[0029] Figure 2 Fig. 7 is a diagram showing the change of the breaking strength and breaking elongation of the SF / PEG macromolecular film with the PEG content;

[0030] Figure 3 Fig. 8 is a diagram showing the change of the dissolution rate of the SF / PEG macromolecular film with the PEG content;

[0031] Figure 4 Fig. 9 is a centrifugal experiment diagram of solutions with different TA / PEG ratios;

[0032] Figure 5 Fig. 10 is a pig skin adhesion experiment diagram of antibacterial films with different TA / PEG ratios;

[0033] Figure 6 Fig. 11 is a diagram showing the antibacterial effect of different samples on bacteria;

[0034] Figure 7 Fig. 12 is a diagram showing the antibacterial rate of different samples after 12h of co-culture with bacteria. DETAILED DESCRIPTION

[0035] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with the accompanying drawings and examples. However, it should be understood that the specific examples described herein are only used to explain the present application and are not used to limit the scope of the present application. In addition, in the following description, the description of the known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.

[0036] The present application is a preparation method of an antibacterial film with TA / PEG micro-nano fibers, which specifically comprises the following steps:

[0037] S1, a natural biological macromolecule and polyethylene glycol are taken and dissolved in purified water to obtain a natural biological macromolecule aqueous solution and a polyethylene glycol aqueous solution; the natural biological macromolecule aqueous solution and the polyethylene glycol aqueous solution are mixed uniformly to obtain a mixed solution; the natural biological macromolecule is selected from one of silk fibroin, collagen, sodium hyaluronate or gelatin;

[0038] In a feasible embodiment, the mass ratio of the natural biological macromolecule to the polyethylene glycol is 9:1~7:3.

[0039] S2, the mixed solution obtained in step S1 is poured into a mold and dried, and ultraviolet lamp irradiation is performed to obtain a macromolecular film; specifically, the drying temperature is 32~42℃; the wavelength of the ultraviolet light is 254nm, and the irradiation time is 1.5~2.5h.

[0040] S3, tannic acid and polyethylene glycol are taken and dissolved in an alcohol solution to obtain a tannic acid alcohol solution and a polyethylene glycol alcohol solution; the tannic acid alcohol solution and the polyethylene glycol alcohol solution are mixed uniformly to obtain a TA / PEG alcohol solution; specifically, the mass concentration of tannic acid is 5%~25%, and the mass concentration of polyethylene glycol is 2%~10%; the alcohol solution is an ethanol aqueous solution with an ethanol volume concentration of 50%~95%;

[0041] S4, the TA / PEG alcohol solution obtained in step S3 is subjected to spinning treatment with the macromolecular film obtained in step S2; specifically, the TA / PEG alcohol solution obtained in step S3 is poured into a syringe of an electrospinning machine, and the macromolecular film obtained in step S2 is fixed on a collector for spinning; the diameter of the micro-nano fibers obtained by electrospinning of the TA / PEG alcohol solution is 50~100nm.

[0042] S5, the macromolecular film after spinning treatment is taken out and soaked in purified water, and finally dried to obtain an antibacterial film; specifically, the soaking time is 25~35min, and the drying temperature is 32~42℃.

[0043] In a feasible embodiment, the polyethylene glycol in steps S1 and S3 is polyethylene glycol 2000.

[0044] In a feasible embodiment, the mass ratio of solute in the tannin alcohol solution and the polyethylene glycol alcohol solution in step S3 is 1.5:1-2:1.

[0045] Example 1

[0046] This example relates to the selection of the macromolecular film being SF and PEG. This example is to optimize the performance of the macromolecular film, to investigate the influence of the ratio of SF and PEG, different molecular weight PEG, and different drying temperatures on the mechanical properties and solubility of the macromolecular film, to further illustrate and verify the preparation system of the present application, including the following steps:

[0047] 1. Preparation of macromolecular films with different molecular weights of PEG

[0048] First, prepare 10% SF aqueous solution, PEG600 aqueous solution, PEG2000 aqueous solution, PEG4000 aqueous solution, PEG8000 aqueous solution and PEG20000 aqueous solution, respectively, then mix the SF aqueous solution and the PEG aqueous solution uniformly according to the ratio of SF:PEG=8:2, pour 10g of the mixed and uniform solution into a mold (10cm×10cm) and dry at 37℃, finally irradiate under a UV lamp with a wavelength of 254nm for 2h to prepare SF / PEG films with different molecular weights of PEG. Cut the SF / PEG films with different ratios into 1cm×3cm samples, measure the breaking strength and breaking elongation rate by a universal material testing machine, the pulling speed is 50mm / min, take 3 parallel samples for each group, and take the average value as the result.

[0049] Figure 1 is the change of the breaking strength and breaking elongation rate of the SF / PEG macromolecular film with the increase of the molecular weight of PEG. As shown in the figure, with the increase of the molecular weight of PEG, the breaking strength of the SF / PEG macromolecular film presents a trend of first increasing and then decreasing, and reaches the maximum value of 26.42MPa when the molecular weight of PEG is 2000, while the breaking elongation rate presents a trend of first rapidly decreasing and then tending to be flat, and is only 22% when the molecular weight of PEG is 4000.

[0050] Therefore, the molecular weight of PEG is determined to be 2000.

[0051] 2. Preparation of macromolecular films with different ratios of SF and PEG 2000

[0052] First, 10% SF aqueous solution and PEG2000 aqueous solution were prepared respectively, then SF aqueous solution and PEG2000 aqueous solution were mixed in the ratio of SF:PEG = 10:0, 9:1, 8:2, 7:3, 6:4, and then poured into the mold and dried at 37℃, and finally irradiated under the ultraviolet lamp with a wavelength of 254nm for 1.5h to prepare SF / PEG films with different ratios. The mechanical properties and dissolution rate of SF / PEG films were tested.

[0053] The SF / PEG films with different ratios were cut into 2.5cm x 2.5cm squares, accurately weighed, and then placed in 20ml PBS solution and placed in a 37℃ oven for 24h, then dried to constant weight, and the dissolution rate of SF / PEG films was calculated by weighing method.

[0054] Figure 2 Figure 2 is a graph showing the change of the breaking strength and breaking elongation of SF / PEG macromolecular films with the change of PEG content. The addition of a small amount of PEG to the silk fibroin film can not only enhance the breaking strength of the material, but also improve the breaking elongation of the material. The breaking strength of the macromolecular film with 10% PEG content reaches a maximum value of 37.08MPa. Further increasing the PEG content can improve the flexibility of the film, but causes the breaking strength to decrease. When the PEG content is 30%, the breaking elongation of the macromolecular film reaches a maximum value of 124%, but its breaking strength decreases to 17.34MPa. This is because the addition of PEG causes the conformational transition of silk fibroin from random coil to β-sheet, which will cause the increase of the breaking strength of the macromolecular film. On the other hand, due to its good compatibility with silk fibroin, PEG will be distributed in the non-crystalline region of silk fibroin in the form of random coil in the composite film, acting as a plasticizer, making the silk fibroin molecules easy to slip under external force, thereby leading to the decrease of the breaking strength and the increase of the flexibility of the macromolecular film.

[0055] Figure 3 Figure 3 is a graph showing the change of the dissolution rate of SF / PEG macromolecular films with the change of PEG content. As shown in the figure, the addition of a small amount of PEG can achieve the purpose of reducing the dissolution rate of silk fibroin film. With the increase of PEG content, the dissolution rate of SF / PEG macromolecular film gradually increases.

[0056] Therefore, the ratio of SF and PEG2000 is selected to be 9:1~7:3.

[0057] 3. Preparation of macromolecular films at different drying temperatures

[0058] First, 10% SF aqueous solution and PEG2000 aqueous solution were respectively configured, then SF aqueous solution and PEG2000 aqueous solution were mixed uniformly according to the ratio of SF:PEG=7:3, poured into a mold, and dried at 25℃, 37℃, 60℃ and 80℃ respectively, and finally irradiated under a UV lamp with a wavelength of 254nm for 2.5h to prepare SF / PEG film.

[0059] When the temperature is higher than 60℃, the water on the surface of the macromolecular film volatilizes too fast, causing cracks on the surface of the film, and because the temperature is too high, the water volatilizes completely, so the macromolecular film prepared is too brittle. When the temperature is lower, the molecular motion is sufficient, so the surface of the macromolecular film is relatively flat and uniform, and the water content is moderate, so the macromolecular film is relatively soft. However, when the temperature is 25℃, it takes nearly 24h to form a film, which is too long.

[0060] Therefore, the drying temperature of the macromolecular film is set to 32~42℃.

[0061] The above results show that the macromolecular film can be quickly, simply and efficiently prepared by the one-step solvent evaporation method, and the macromolecular film prepared has good mechanical properties and is not easy to dissolve in water.

[0062] Example 2

[0063] In this embodiment, TA / PEG micro-nano fibers are selected, and the optimization of the performance of TA / PEG micro-nano fibers is related, and the influence of TA and PEG on the performance of the antibacterial film is investigated.

[0064] 1. Preparation of TA / PEG alcohol solutions with different molecular weights of PEG

[0065] 10% TA alcohol solution, PEG2000 alcohol solution, PEG8000 alcohol solution and PEG20000 alcohol solution were respectively configured, and the solvent was 50% ethanol / water solution; according to the ratio of TA:PEG=1.5:1, PEG alcohol solution was slowly added into TA alcohol solution, and stirred for 5min.

[0066] After TA / PEG2000 alcohol solution, TA / PEG8000 alcohol solution and TA / PEG20000 alcohol solution were placed for 10min, it was found that TA / PEG8000 alcohol solution and TA / PEG20000 alcohol solution were stratified, and TA and PEG formed an adhesive and deposited at the bottom of the beaker; while TA / PEG2000 alcohol solution was still a uniform and clear solution.

[0067] Therefore, the molecular weight of PEG is set to 2000.

[0068] 2. Determine the volume of ethanol in the solvent

[0069] Respectively configure the ethanol / water solution with the volume of ethanol of 40%, 50%, 75%, 95%, and then configure the TA alcohol solution and PEG 2000 alcohol solution with the mass concentration of 5% with the ethanol / water solution with different volume ratios as the solvent; mix the TA alcohol solution and PEG 2000 alcohol solution according to the ratio of TA:PEG 2000=1.5:1.

[0070] It is found that when the ethanol / water solution with the volume of ethanol of 40% is used as the solvent, the TA alcohol solution and the PEG 2000 alcohol solution form a white suspension liquid after mixing, and after standing for 1 h, the white particles are observed to deposit to form a red-brown adhesive, and the upper layer is a uniform transparent solution; while when the ethanol / water solution with the volume of ethanol of 50%, 75%, 95% is used as the solvent, the TA alcohol solution and the PEG 2000 alcohol solution form a uniform clear solution after mixing, and no obvious change is observed after standing for 1 h.

[0071] Therefore, the volume of ethanol in the solvent is 50%-95%.

[0072] 3. Configure TA / PEG 2000 alcohol solutions with different ratios

[0073] Respectively configure the TA alcohol solution and the PEG 2000 alcohol solution with the mass concentration of 5% with the ethanol / water solution with the volume of ethanol of 50% as the solvent, then fix the PEG 2000 addition amount, and mix the TA alcohol solution and the PEG 2000 alcohol solution in a centrifuge tube according to the ratio of TA:PEG=2.5:1, 2:1, 1.5:1, 1:1, and centrifuge at the speed of 4000 r / min for 15 min. After centrifugation, the upper solution is taken out for drying and weighing, and the results are recorded.

[0074] As shown in Figure 4 Without changing the PEG 2000 addition amount, with the increase of the TA content, the content of the solute in the upper solution after centrifugation presents a trend of first decreasing and then increasing, and the minimum value is reached when TA:PEG 2000=1.5:1, that is, the content of the solute in the upper solution after centrifugation accounts for 3.43% of the total amount of the solute added, that is, the reaction of TA and PEG 2000 is the most sufficient.

[0075] 4. Prepare antibacterial films with different ratios of TA and PEG 2000

[0076] Respectively configure the SF aqueous solution and the PEG 2000 aqueous solution with the mass concentration of 10%, take 1.8 g of the PEG 2000 aqueous solution in a beaker, add 4.2 g of the SF aqueous solution, mix uniformly, and then dry at 32°C to form a film, and finally irradiate under the ultraviolet lamp with the wavelength of 254 nm for 2 h to obtain a macromolecular film.

[0077] TA and PEG 2000 alcohol solution with a mass concentration of 5% were prepared respectively, and 50% ethanol / water solution was used as the solvent. Then, the TA alcohol solution and the PEG 2000 alcohol solution were mixed in a ratio of TA:PEG 2000 = 2.5:1, 2:1, 1.5:1, and 1:1, respectively. After being stirred uniformly, 3 ml of each solution was poured into a syringe of an electrospinning machine, and a macromolecular film (10 cm x 10 cm) was fixed on a collector. The spinning was started, and the diameter of the TA / PEG micro-nano fiber was controlled to be 50-100 nm. After the spinning was completed, the macromolecular film was removed and soaked in purified water for 25 min to wash away the substances not adsorbed on the surface and the free tannic acid. Finally, the macromolecular film was taken out and dried to obtain an antibacterial film.

[0078] Fresh pigskin was prepared, the fat layer was removed, the pigskin was cleaned, and the pigskin was cut into rectangular blocks (3 cm x 1 cm). The antibacterial film was cut into rectangular blocks (3 cm x 1 cm), and one end of the antibacterial film was adhered to one end of the pigskin, with an overlapping area of 1 cm x 1 cm. The stretching was performed at room temperature using a biomaterial testing machine at a stretching rate of 50 mm / min. The stretching process was measured three times for each group, and the average value of the sample results was taken.

[0079] Figure 5 The pigskin adhesion experiment of the antibacterial film with different TA / PEG ratios was performed. With the increase of the TA content, the bonding strength of the antibacterial film showed a trend of first increasing and then decreasing. When TA:PEG 2000 = 1.5, the bonding strength was the highest, reaching 17 kPa.

[0080] The bonding strength of the TA / PEG micro-nano fiber is mainly affected by two factors, the first being the intrinsic cohesive interaction, and the second being the bonding interaction with the pigskin. With the increase of the TA content, the number of hydrogen bonds formed between TA and PEG increases, until TA:PEG = 1.5, when most of the -O- in PEG participates in the formation of hydrogen bonds, the crosslinking is tight, and the remaining free phenolic hydroxyl groups bond with the pigskin, and the bonding strength reaches the highest. When the TA content continues to increase, the free phenolic hydroxyl groups are too much, although the active groups between the pigskin and the TA increase, the crosslinking network is not tight enough, the cohesive interaction decreases, and the bonding strength is slightly lower than that of TA:PEG = 1.5.

[0081] According to the results of this example, the ratio of TA and PEG 2000 was determined to be 1.5:1-2:1.

[0082] Example 3:

[0083] This example relates to the selection of SF / PEG, collagen / PEG, gelatin / PEG, and hyaluronic acid / PEG macromolecular films. This example verifies the antibacterial property of the antibacterial film, including the following steps:

[0084] First, the mass concentration of 10% of the SF aqueous solution, collagen aqueous solution, gelatin aqueous solution, hyaluronic acid aqueous solution and PEG 2000 aqueous solution were configured respectively, 1.8g PEG 2000 aqueous solution was taken in a beaker, and 4.2g SF aqueous solution, collagen aqueous solution, gelatin aqueous solution, hyaluronic acid aqueous solution was added respectively, and then mixed uniformly, and dried at 42℃ to form a film, and finally irradiated under a UV lamp with a wavelength of 254nm for 2h, to obtain a macromolecular film.

[0085] Then, 0.3g TA was weighed to prepare a TA alcohol solution with a mass concentration of 25%, and 0.2g PEG 2000 was weighed to prepare a PEG 2000 alcohol solution with a mass concentration of 2%, and the solvent was 75% ethanol / water solution; the PEG 2000 alcohol solution was slowly added to the TA alcohol solution, stirred uniformly, then poured into the syringe of the electrospinning machine, and the macromolecular film (10cm×10cm) was fixed on the collector, and the spinning was started; after the spinning was finished, the macromolecular film was taken out and soaked in purified water for 35min, and the surface substances and free tannic acid that were not adsorbed were washed away, and finally dried to obtain an antibacterial film.

[0086] Staphylococcus aureus and Escherichia coli were selected as representative bacteria of gram-positive bacteria and gram-negative bacteria, and the colony counting method was used for the experiment to calculate the antibacterial rate of the antibacterial film on the two bacteria.

[0087] Figure 6 Fig. 1 is the antibacterial effect diagram of different samples on bacteria. Figure 6 Figs. 1(a~e) are the antibacterial effect diagrams of the blank control, SF / PEG antibacterial film, collagen / PEG antibacterial film, gelatin / PEG antibacterial film, and hyaluronic acid / PEG antibacterial film on Escherichia coli respectively, Figure 6 Figs. 1(a’~e’) are the antibacterial effect diagrams of the blank control, SF / PEG antibacterial film, collagen / PEG antibacterial film, gelatin / PEG antibacterial film, and hyaluronic acid / PEG antibacterial film on Staphylococcus aureus respectively. Figure 7 Fig. 1 is the antibacterial rate diagram of different samples after 12h of co-culture with bacteria; wherein (a) is the antibacterial rate of SF / PEG antibacterial film, collagen / PEG antibacterial film, gelatin / PEG antibacterial film, and hyaluronic acid / PEG antibacterial film on Escherichia coli, which is 97.8%, 95.7%, 93.4%, and 94.3% respectively; and (b) is the antibacterial rate of SF / PEG antibacterial film, collagen / PEG antibacterial film, gelatin / PEG antibacterial film, and hyaluronic acid / PEG antibacterial film on Staphylococcus aureus, which is 100%, 98.7%, 96.4%, and 97.3% respectively.

[0088] The blank control group had dense colonies, large in number, and covered the entire agar plate. For S. aureus, there were no obvious colonies on the SF / PEG antibacterial membrane agar plate, and only a small amount of colonies were sporadically distributed on the collagen / PEG antibacterial membrane, gelatin / PEG antibacterial membrane, and hyaluronic acid / PEG antibacterial membrane agar plates, indicating that the SF / PEG antibacterial membrane, collagen / PEG antibacterial membrane, gelatin / PEG antibacterial membrane, and hyaluronic acid / PEG antibacterial membrane had a strong inhibitory effect on the growth of S. aureus. The antibacterial effect on E. coli was slightly weaker, but the antibacterial effect was still higher than 90%.

[0089] Example 4

[0090] This example selected SF / PEG macromolecular membrane, and involved the stability of TA / PEG micro-nano fibers prepared by mixing PEG 2000 and TA to the macromolecular membrane adsorption.

[0091] A 10% SF aqueous solution and a 10% PEG 2000 aqueous solution were respectively prepared, 1.8 g of the PEG 2000 aqueous solution was taken in a beaker, and 4.2 g of the SF aqueous solution was added, then the mixture was dried at 37°C to form a film, and finally the film was irradiated under a UV lamp with a wavelength of 254 nm for 2 h to obtain a macromolecular film.

[0092] A 10% TA alcohol solution and a 10% PEG 2000 alcohol solution were respectively prepared, and the solvents were both 95% ethanol / water solutions; according to the ratio of TA:PEG = 1.5:1, the PEG 2000 alcohol solution was slowly added to the TA alcohol solution, and then the mixture was stirred uniformly and poured into the syringe of the electrospinning machine, and the macromolecular film (10 cm x 10 cm) was fixed on the collector, and the spinning was started, and the diameter of the TA / PEG micro-nano fibers was 50-100 nm; after the spinning was completed, the macromolecular film was taken out and soaked in purified water for 30 min to wash away the substances not adsorbed on the surface and the free tannic acid, and finally the macromolecular film was taken out and dried to obtain an antibacterial membrane. 2 mg / ml of FeCl3 solution was added to the surface of the antibacterial membrane, and then the antibacterial membrane was naturally air-dried.

[0093] After the FeCl3 solution was added to the surface of the antibacterial membrane, the antibacterial membrane turned purple, which was due to the unbound phenolic hydroxyl groups in the tannic acid that could form a purple complex with Fe 3+ The TA / PEG micro-nano fibers with a diameter of 50-100 nm on the surface of the SF / PEG macromolecular film showed good adsorption.

[0094] Comparative Example 1

[0095] Respectively configure the mass concentration of 10% SF aqueous solution and PEG 2000 aqueous solution, take 1.8 g PEG 2000 aqueous solution in a beaker, then add 4.2 g SF aqueous solution, mix uniformly, and then dry at 37℃ to form a film, finally irradiate under the ultraviolet lamp with a wavelength of 254 nm for 2 h, to obtain a macromolecular film.

[0096] Take 0.3 g TA to prepare a TA aqueous solution with a mass concentration of 10%, and take 0.2 g PEG 2000 to prepare a PEG aqueous solution with a mass concentration of 10%; slowly add the PEG aqueous solution into the TA aqueous solution, shake, and then pour into the syringe of the electrospinning machine; fix the SF / PEG macromolecular film (10 cm x 10 cm) on the collector, and start spinning; after spinning, take down the SF / PEG macromolecular film and soak it in purified water for 30 min, to wash away the substances not adsorbed on the surface and the free tannic acid, and finally take it out to dry, to obtain an antibacterial film. Add 2 mg / ml FeCl3 solution on the surface of the antibacterial film, and then air dry naturally.

[0097] The TA aqueous solution and the PEG aqueous solution after mixing are white suspensions, and direct electrospinning is performed, to obtain TA / PEG particles with a diameter of 50-100 nm. After adding FeCl3 solution on the surface of the antibacterial film, the antibacterial film does not turn purple, indicating that the TA / PEG particles on the surface of the antibacterial film are all dissolved in water during the washing process, and are not adsorbed on the surface of the macromolecular film.

[0098] Comparative Example 2

[0099] Respectively configure the mass concentration of 10% SF aqueous solution and PEG 2000 aqueous solution, take 1.8 g PEG 2000 aqueous solution in a beaker, then add 4.2 g SF solution, mix uniformly, and then dry at 37℃ to form a film, finally irradiate under the ultraviolet lamp with a wavelength of 254 nm for 2 h, to obtain a macromolecular film.

[0100] Take 0.2 g TA to prepare a TA alcohol solution with a mass concentration of 20%, and take 0.2 g PEG 2000 to prepare a PEG alcohol solution with a mass concentration of 10%, and the solvent is 50% ethanol / water solution; slowly add the PEG alcohol solution into the TA alcohol solution, stir uniformly, and then pour into the mold (10 cm x 10 cm) containing the macromolecular film, and try to flow uniformly; dry the solvent on the surface of the macromolecular film to form a layer of TA / PEG adhesive, then soak it in purified water for 30 min, to wash away the substances not adsorbed on the surface and the free tannic acid, and finally take it out to dry, to obtain an antibacterial film.

[0101] The TA / PEG adhesive on the surface of the antibacterial film prepared by direct pouring self-leveling is unevenly distributed, and after the antibacterial film is adhered to the skin for 5 min and then removed, it is found that the TA / PEG adhesive will be left on the surface of the skin, and it is not easy to clean.

[0102] The above results show that, compared with the method of allowing the TA / PEG alcohol solution to self-level and dry into a film, the TA / PEG micro-nano fiber with a diameter of 50-100 nm prepared by the electrospinning technology can be uniformly adsorbed on the surface of the macromolecular film.

[0103] Comparative Example 3

[0104] The SF aqueous solution with a mass concentration of 10% and the PEG 2000 aqueous solution were respectively configured, 1.8 g of the PEG 2000 aqueous solution was taken in a beaker, 4.2 g of the SF aqueous solution was added, and after being mixed uniformly, it was dried into a film at 35°C, and finally irradiated under the ultraviolet lamp with a wavelength of 254 nm for 2 h, to obtain a macromolecular film.

[0105] The TA alcohol solution with a mass concentration of 5% and the PEG 2000 alcohol solution were respectively configured, the solvent was 50% ethanol / water solution, then the TA alcohol solution and the PEG 2000 alcohol solution were mixed according to the ratio of TA:PEG 2000=1.5:1, 3 mL of the mixture was poured into the syringe of the electrospinning machine after being stirred uniformly, and the macromolecular film (10 cm×10 cm) was fixed on the collector, the spinning was started, and the diameter of the TA / PEG micro-nano fiber was controlled to be 150-200 nm; after the spinning was finished, the macromolecular film was taken down and soaked in purified water for 30 min, the substances not adsorbed on the surface and the free tannic acid were washed away, and finally the antibacterial film was taken out and dried, and the pigskin adhesion test was carried out.

[0106] The results are as follows, the bonding strength of the TA / PEG micro-nano fiber with a diameter of 150-200 nm is 15.34 KPa, which is lower than 17 KPa of the TA / PEG micro-nano fiber with a diameter of 50-100 nm.

[0107] The reason is that the TA / PEG micro-nano fiber with a diameter of 50-100 nm can well infiltrate the pigskin, and plays a mechanical pinning role on the rough pigskin surface, which is helpful for adhesion.

[0108] The above only describes the preferred embodiments of the present application and should not be used to limit the present application, and any modification, equivalent replacement or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing an antibacterial membrane with TA / PEG micro / nanofibers, characterized in that, Specifically, the steps include the following: S1. Take natural biomacromolecules and polyethylene glycol, and dissolve them separately in purified water to obtain aqueous solutions of natural biomacromolecules and polyethylene glycol; mix the aqueous solutions of natural biomacromolecules and polyethylene glycol evenly to obtain a mixed solution; the natural biomacromolecules are selected from one of silk fibroin, collagen, sodium hyaluronate or gelatin, and the mass ratio of natural biomacromolecules to polyethylene glycol is 9:1 to 7:3; S2. Pour the mixed solution obtained in step S1 into a mold, dry it, and irradiate it with ultraviolet light to obtain a macromolecular film. S3. Take tannic acid and polyethylene glycol, and dissolve them separately in alcohol solutions to obtain tannic acid alcohol solution and polyethylene glycol alcohol solution; mix the tannic acid alcohol solution and polyethylene glycol alcohol solution evenly to obtain TA / PEG alcohol solution, wherein the mass ratio of solute in the tannic acid alcohol solution and polyethylene glycol alcohol solution is 1.5:1~2:1; S4. The TA / PEG alcohol solution obtained in step S3 is spun with the macromolecular membrane obtained in step S2. S5. Remove the macromolecular membrane after spinning and immerse it in purified water. Finally, take it out and dry it to obtain an antibacterial membrane. In steps S1 and S3, polyethylene glycol is selected as polyethylene glycol 2000; In step S2, the drying temperature is 32~42℃; the wavelength of the ultraviolet light is 254nm, and the irradiation time is 1.5~2.5h; In step S3, the mass concentration of tannic acid is 5%~25%, and the mass concentration of polyethylene glycol is 2%~10%; the alcohol solution is an aqueous solution of ethanol with a volume concentration of 50%~95%.

2. The method for preparing an antibacterial membrane with TA / PEG micro / nanofiber as described in claim 1, characterized in that: The specific operation of step S4 is as follows: the TA / PEG alcohol solution obtained in step S3 is poured into the syringe of the electrospinning machine, and the macromolecular membrane obtained in step S2 is fixed on the collector for spinning; the micro-nano fibers obtained by electrospinning the TA / PEG alcohol solution have a diameter of 50~100nm.

3. The method for preparing an antibacterial membrane with TA / PEG micro / nanofiber as described in claim 1, characterized in that: In step S5, the soaking time is 25~35 minutes and the drying temperature is 32~42℃.

4. An antibacterial membrane containing TA / PEG micro / nanofibers, characterized in that: It is prepared by the method for preparing an antibacterial membrane with TA / PEG micro / nanofiber as described in any one of claims 1 to 3.

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