Tussah silk gland protein fiber, preparation method and application thereof, and drug-loaded tussah silk gland protein fiber

Abstract

The invention provides a tussah silk gland protein fiber, a preparation method and application thereof and a drug-loaded tussah silk gland protein fiber, and belongs to the technical field of functional materials. The preparation method comprises the following steps: spinning a raw material mixture in the presence of a curing agent solution to obtain tussah silk gland protein fibers; the raw material mixture comprises a tussah silk gland protein solution and a sodium alginate solution, the tussah silk gland protein solution comprises tussah silk gland protein, a Tris. HCl solution and a lauryl sodium sulfate solution, the concentration of the Tris. HCl solution is 0.01-0.012 g / mL, the concentration of the lauryl sodium sulfate solution is 0.05-0.1 g / mL, the volume ratio of the Tris. HCl solution to the lauryl sodium sulfate solution is (7-9): 1, and the concentration of the sodium alginate solution is 0.03-0.04 g / mL. The tussah silk gland protein fiber provided by the invention can be used as a novel functional fiber material, the application range of tussah silk is expanded, and a new thought is provided for developing the functional fiber material.

Description

Technical Field

[0001] The invention relates to the technical field of functional materials, in particular to tussah silk gland protein fiber and a preparation method and application thereof, and drug-loaded tussah silk gland protein fiber. Background Art

[0002] Tussah silkworms belong to the genus Tussah of the family Bombycidae in the order Lepidoptera. They are named after their love of eating tussah leaves. They were called spring silkworms, oak silkworms, and mountain silkworms in ancient times. Tussah silkworms are one of the most precious biological resources of mankind. The cocoons of tussah silkworms can be reeled into silk, which is mainly used to weave tussah silk; the pupae of tussah silkworms are edible and can also be used as medicinal materials. In addition, there are reports in the relevant technology that tussah silkworm eggs are used to prepare tussah silkworm egg powder. In addition to preserving conventional nutrients, it can also preserve the activity of biologically active substances in tussah silkworm eggs. Its function is completely equivalent to that of fresh eggs, and it is suitable for the production of many advanced health products and medicines. With the continuous deepening and development of the comprehensive utilization of tussah silkworm resources, the economic and social benefits of tussah silkworm production will become more and more prominent, and will have a significant impact on people's food, clothing, housing and transportation. How to further carry out in-depth research and utilization of tussah silkworm resources is of specific and important significance. Summary of the invention

[0003] The purpose of the present invention is to provide tussah silk gland protein fiber and its preparation method and application, and drug-loaded tussah silk gland protein fiber. The tussah silk gland protein fiber provided by the present invention expands the application scope of tussah silkworm and provides a new idea for the development of functional fiber materials.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing tussah silk gland protein fiber, comprising the following steps:

[0006] Providing a raw material mixture, the raw material mixture comprising a tussah silk gland protein solution and a sodium alginate solution, the tussah silk gland protein solution comprising tussah silk gland protein, a Tris·HCl solution and a sodium dodecyl sulfate solution, the concentration of Tris·HCl in the Tris·HCl solution being 0.01 to 0.012 g / mL, the concentration of the sodium dodecyl sulfate solution being 0.05 to 0.1 g / mL, the volume ratio of the Tris·HCl solution to the sodium dodecyl sulfate solution being 7 to 9:1, and the concentration of the sodium alginate solution being 0.03 to 0.04 g / mL;

[0007] In the presence of a curing agent solution, the raw material mixture is spun to obtain the tussah silk gland protein fiber.

[0008] Preferably, the pH value of the Tris·HCl solution is 8-12.

[0009] Preferably, the concentration of tussah silk gland protein in the tussah silk gland protein solution is 0.01-0.05 g / mL; the concentration of the sodium alginate solution is 0.01-0.08 g / mL; and the volume ratio of the tussah silk gland protein solution to the sodium alginate solution is 5:5-9:1.

[0010] Preferably, the curing agent in the curing agent solution includes calcium sulfate; and the concentration of the curing agent in the curing agent solution is 0.5-2 mg / mL.

[0011] The present invention provides tussah silk gland protein fibers prepared by the preparation method described in the above technical scheme.

[0012] The present invention provides the use of the tussah silk gland protein fiber described in the above technical solution in the preparation of a drug carrier.

[0013] The invention provides a drug-loaded tussah silk gland protein fiber, comprising the tussah silk gland protein fiber described in the above technical solution and a drug loaded on the tussah silk gland protein fiber.

[0014] Preferably, the drug comprises an antibacterial drug.

[0015] Preferably, the antibacterial drug is an organic antibacterial drug and / or an inorganic antibacterial drug.

[0016] Preferably, the organic antibacterial drug includes one or more of bacitracin, dimethylbiguanide hydrochloride and bovine serum albumin; the inorganic antibacterial drug includes one or more of silver nitrate, borax and dimethyldiallylammonium chloride.

[0017] The invention provides a method for preparing tussah silk gland protein fiber. The method comprises the following steps: providing a raw material mixture, wherein the raw material mixture comprises a tussah silk gland protein solution and a sodium alginate solution, wherein the tussah silk gland protein solution comprises tussah silk gland protein, a Tris·HCl solution and a sodium dodecyl sulfate solution, wherein the concentration of Tris·HCl in the Tris·HCl solution is 0.01-0.012 g / mL, the concentration of the sodium dodecyl sulfate solution is 0.05-0.1 g / mL, the volume ratio of the Tris·HCl solution to the sodium dodecyl sulfate solution is 7-9:1, and the concentration of the sodium alginate solution is 0.03-0.04 g / mL; and spinning the raw material mixture in the presence of a curing agent solution to obtain the tussah silk gland protein fiber. The present invention uses tussah silk gland protein as raw material, which has unique protein properties and good biocompatibility, and sodium alginate as a thickener, and prepares tussah silk gland protein fibers in the presence of a curing agent solution, which can be used as a new functional fiber material, expand the application range of tussah silk, and provide a new idea for the development of functional fiber materials. At the same time, the method of the present invention has good process stability and is suitable for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The photos of the fibers obtained in Example 1 with a quantitative curing agent solution (4 mL of 0.01 g / mL CaSO4 solution) and different volume ratios of the tussah silk gland protein solution and the sodium alginate solution;

[0019] Figure 2 The photographs of tussah silk gland protein fibers obtained by drying at room temperature under different volume ratios of tussah silk gland protein solution and sodium alginate solution in Example 1 are shown;

[0020] Figure 3 This is a physical picture of the tussah silk gland protein fiber prepared in Example 2;

[0021] Figure 4 This is a graph showing the antibacterial test results of the blank tussah silk gland protein fiber prepared in Example 2;

[0022] Figure 5 This is a graph showing the antibacterial (Escherichia coli) test results of the antibacterial tussah silk gland protein fiber prepared in Example 2;

[0023] Figure 6 This is a graph showing the antibacterial (Staphylococcus aureus) test results of the antibacterial tussah silk gland protein fiber prepared in Example 2;

[0024] Figure 7 This is a physical picture of the antibacterial tussah silk gland protein fiber containing different drugs in Example 3;

[0025] Figure 8 This is a test diagram of the antibacterial performance of the antibacterial tussah silk gland protein fiber in Example 3 (Escherichia coli culture medium);

[0026] Fig. 9 This is a test diagram of the antibacterial performance of the antibacterial tussah silk gland protein fiber in Example 3 (Staphylococcus aureus culture medium);

[0027] Fig.10 This is a test diagram of the antibacterial performance of the antibacterial tussah silk gland protein fiber in Example 3 (Aspergillus niger culture medium);

[0028] Fig.11 This is a test diagram of the antibacterial performance of the antibacterial tussah silk gland protein fiber in Example 3 (Candida albicans culture medium);

[0029] Fig.12 This is a test diagram showing the effect of different volume ratios of tussah silk gland protein solution to sodium alginate solution on the release performance of different drugs in Example 3;

[0030] Fig.13This is a graph showing the effect of different concentrations of tussah silk gland protein solutions on the properties of tussah silk gland protein fibers;

[0031] Fig.14 This is a physical picture of the tussah silk gland protein fiber after stretching. DETAILED DESCRIPTION

[0032] The present invention provides a method for preparing tussah silk gland protein fiber, comprising the following steps:

[0033] Providing a raw material mixture, the raw material mixture comprising a tussah silk gland protein solution and a sodium alginate solution, the tussah silk gland protein solution comprising tussah silk gland protein, a Tris·HCl solution and a sodium dodecyl sulfate solution, the concentration of Tris·HCl in the Tris·HCl solution being 0.01 to 0.012 g / mL, the concentration of the sodium dodecyl sulfate solution being 0.05 to 0.1 g / mL, the volume ratio of the Tris·HCl solution to the sodium dodecyl sulfate solution being 7 to 9:1, and the concentration of the sodium alginate solution being 0.03 to 0.04 g / mL;

[0034] In the presence of a curing agent solution, the raw material mixture is spun to obtain the tussah silk gland protein fiber.

[0035] In the present invention, unless otherwise specified, the raw materials used are commercially available products well known to those skilled in the art or are prepared by methods well known to those skilled in the art.

[0036] The invention first prepares a raw material mixture, wherein the raw material mixture comprises a tussah silk gland protein solution and a sodium alginate solution, wherein the tussah silk gland protein solution comprises tussah silk gland protein, a Tris·HCl solution and a sodium dodecyl sulfate solution; the concentration of Tris·HCl in the Tris·HCl solution is 0.01-0.012 g / mL, specifically 0.012 g / mL; the pH value of the Tris·HCl solution can be 7.8-8.2, specifically 8; the concentration of the sodium dodecyl sulfate solution is 0.05-0.1 g / mL, further 0.05-0.08 g / mL (if not specifically stated, 0.05 g / mL in the invention is also recorded as 5%, and the subsequent related situations are not repeated), and the volume ratio of the Tris·HCl solution to the sodium dodecyl sulfate solution is 7-9, further 8-9:1.

[0037] As an embodiment of the present invention, the concentration of tussah silk gland protein in the tussah silk gland protein solution can be 0.02-0.1 g / mL, specifically 0.02 g / mL, 0.04 g / mL, 0.06 g / mL, 0.08 g / mL or 0.1 g / mL. As an embodiment of the present invention, the method for obtaining tussah silk glands comprises the following steps: using clean tweezers to tear open the tussah epidermis at the position of the third circle from the bottom of the tail of the tussah, slowly pulling out its silk glands, placing them in a clean glass dish and slowly washing them with distilled water for several times until the distilled water is no longer turbid, then wiping the moisture on the surface of the silk glands with filter paper, and storing them in a refrigerator for standby use; the tussah silk glands are transparent, elastic and tough, not easy to break, and sticky, and will oxidize rapidly when placed in the air and are difficult to dissolve in water.

[0038] As an embodiment of the present invention, the preparation method of the tussah silk gland protein solution comprises the following steps: mixing tussah silk gland, Tris·HCl solution and sodium dodecyl sulfate solution, sequentially performing oscillation treatment and centrifugation, and collecting the supernatant as the tussah silk gland protein solution. As an embodiment of the present invention, the rotation speed of the oscillation treatment can be 50-80r / min, specifically 60r / min; the time of the oscillation treatment can be 1.5-2.5h, specifically 2h. As an embodiment of the present invention, the rotation speed of the centrifugation can be 7000-9000r / min, specifically 8000r / min; the time of the centrifugation can be 1-3min, specifically 2min.

[0039] In the present invention, the concentration of the sodium alginate solution is 0.03-0.04 g / mL; the volume ratio of the tussah silk gland protein solution to the sodium alginate solution can be 2:8-8:2, specifically 2:8, 3:7, 4:6, 5:5, 6:4, 8:5, 7:3, 8:2.

[0040] After obtaining the raw material mixture, the present invention spins the raw material mixture in the presence of a curing agent solution to obtain the tussah silk gland protein fiber. As an embodiment of the present invention, the curing agent in the curing agent solution may include calcium sulfate, and the concentration of the curing agent in the curing agent solution may be 0.5 to 2 mg / mL, specifically 0.5 mg / mL, 0.6 mg / mL, 0.7 mg / mL, 0.8 mg / mL, 0.9 mg / mL, 1 mg / mL, 1.3 mg / mL, 1.5 mg / mL, 1.7 mg / mL or 2 mg / mL.

[0041] The spinning method described in the present invention is specifically wet spinning, and the wet spinning method can specifically include the following steps: extracting the raw material mixture with a syringe, connecting a rubber hose with a length of 20 cm at one end of the injection port, installing a needle connector at the other end, and fixing a needle with a diameter of 0.5 mm; setting the injection volume specification to 10 mL and the injection speed to 5 mL / min on the microfluidic spinning machine; immersing the needle fixed at the other end of the syringe in the curing agent solution, starting the microfluidic spinning machine, and moving the needle at a uniform speed for spinning to ensure that uniform fibers can be spun; after the spinning is completed, the obtained fiber is continued to be placed in the curing agent solution for curing for 15 minutes to obtain the tussah silk gland protein fiber.

[0042] As an embodiment of the present invention, the spinning further includes drying the obtained fibers to obtain the tussah silk gland protein fibers; the drying may be natural drying, and the present invention has no special limitation on the time of the natural drying.

[0043] The present invention provides tussah silk gland protein fibers prepared by the preparation method described in the above technical scheme.

[0044] The present invention provides the use of the tussah silk gland protein fiber described in the above technical solution in the preparation of a drug carrier.

[0045] The present invention provides an antibacterial tussah silk gland protein fiber, comprising the tussah silk gland protein fiber of the above technical solution and a drug loaded on the tussah silk gland protein fiber. As an embodiment of the present invention, the drug may include an antibacterial drug; the antibacterial drug is an organic antibacterial drug and / or an inorganic antibacterial drug; the organic antibacterial drug may include one or more of bacitracin, dimethylbiguanide hydrochloride and bovine serum albumin; the inorganic antibacterial drug may include one or more of silver nitrate, borax and dimethyldiallylammonium chloride.

[0046] As an embodiment of the present invention, the preparation method of the drug-loaded tussah silk gland protein fiber comprises the following steps:

[0047] Mixing the tussah silk gland protein solution, the sodium alginate solution and the antibacterial drug to obtain a raw material mixture;

[0048] In the presence of a curing agent solution, the raw material mixture is spun to obtain the drug-loaded tussah silk gland protein fiber.

[0049] As an embodiment of the present invention, the antibacterial drug can be used directly or in the form of an antibacterial drug solution. As an embodiment of the present invention, the dimethyl biguanide hydrochloride and bovine serum albumin are used directly; the dosage ratio of the dimethyl biguanide hydrochloride to the tussah silk gland protein solution can be 15 mg: 10 mL; the dosage ratio of the bovine serum albumin to the tussah silk gland protein solution can be 15 mg: 10 mL. As an embodiment of the present invention, the bacitracin is used in the form of a bacitracin solution, and the concentration of the bacitracin solution can be 0.1-0.2 g / mL; the volume ratio of the bacitracin solution to the tussah silk gland protein solution can be 1:1. As an embodiment of the present invention, the silver nitrate is used in the form of a silver nitrate solution, and the concentration of the silver nitrate solution can be 0.004-0.01 g / mL, specifically 0.004 g / mL, 0.005 g / mL, 0.006 g / mL, 0.007 g / mL, 0.008 g / mL, 0.009 g / mL or 0.01 g / mL; the volume ratio of the silver nitrate solution to the tussah silk gland protein solution can be 1:2. As an embodiment of the present invention, the borax is used in the form of a borax solution, and the concentration of the borax solution can be 0.01-0.05 g / mL, specifically 0.01 g / mL, 0.02 g / mL, 0.03 g / mL, 0.04 g / mL or 0.05 g / mL; the volume ratio of the borax solution to the tussah silk gland protein solution can be 1:2. As an embodiment of the present invention, the dimethyldiallyl ammonium chloride is used in the form of a dimethyldiallyl ammonium chloride solution, the concentration of the dimethyldiallyl ammonium chloride solution may be 0.6 g / mL; the volume ratio of the dimethyldiallyl ammonium chloride solution to the tussah silk gland protein solution may be 1:1.

[0050] As an embodiment of the present invention, the type, concentration and dosage of the curing agent solution, the spinning method and the drying method can refer to the conditions for preparing tussah silk gland protein fibers in the above technical solution, which will not be repeated here.

[0051] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] The tussah silkworms used in the following examples were purchased from a local farm; the sodium alginate used had a molecular weight of 5 million and was purchased from Qingdao Mingyue Seaweed Group Co., Ltd.

[0053] Unless otherwise specified, the preparation methods of the relevant reagents used in the following examples are as follows:

[0054] Tussah silk gland: Use clean tweezers to tear open the epidermis of the tussah silkworm at the third-to-last circle of the tail of the tussah silkworm, slowly pull out the silk gland, put it in a clean glass dish and slowly wash it with distilled water several times until the distilled water is no longer turbid, then wipe the moisture on the surface of the silk gland with filter paper, and store it in a refrigerator for later use; the tussah silk gland is transparent, elastic and tough, not easy to break, and at the same time sticky, will oxidize quickly when exposed to air, and is difficult to dissolve in water.

[0055] Tris·HCl solution: Weigh 1.211 g of Tris, dissolve it in water and add dilution to a 100 mL conical flask, then add hydrochloric acid dropwise to adjust the pH to 8 to obtain a Tris·HCl solution.

[0056] Sodium dodecyl sulfate (SDS) solution: weigh 50 g of sodium dodecyl sulfate, heat and dissolve it in an appropriate amount of water, and then dilute to 1 L in a volumetric flask to obtain a 5% SDS solution.

[0057] Sodium alginate solution: weigh 4 g of sodium alginate and put it into a beaker, add distilled water to make up to 100 mL, heat to 50°C, and stir thoroughly until the sodium alginate is completely dissolved to obtain a sodium alginate solution with a concentration of 4%. Use the above method to prepare a sodium alginate solution with a concentration of 3%.

[0058] Calcium sulfate solution: weigh 0.1 g of anhydrous calcium sulfate into a beaker, add appropriate amount of water, stir to dissolve, pour into a volumetric flask and make up to 100 mL to obtain a calcium sulfate solution with a concentration of 0.1%; use the above method to prepare calcium sulfate solutions with concentrations of 0.05% and 0.07%.

[0059] Silver nitrate solution: weigh 0.4 g of silver nitrate solid, add distilled water to 100 mL, dissolve it, and obtain a silver nitrate solution with a concentration of 0.4%; prepare silver nitrate solutions with concentrations of 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, and 1% by the above method, place them in brown light-proof bottles, and store them away from light.

[0060] Borax solution: Weigh 0.5 g of borax solid, add distilled water to make up to 50 mL, dissolve it, and obtain a 1% borax solution; use the above method to prepare borax solutions with concentrations of 2%, 3%, 4%, and 5%, respectively, and seal them with aluminum foil for storage.

[0061] Bacitracin solution: weigh 2.5 g of bacitracin, add appropriate amount of water, stir to dissolve, pour into a volumetric flask and make up to 25 mL to obtain a 10% bacitracin solution; prepare a 20% bacitracin solution in the same manner.

[0062] Dimethyldiallylammonium chloride solution: weigh 60 g of dimethyldiallylammonium chloride, add appropriate amount of water, stir to dissolve, pour into a brown volumetric flask and make up to 100 mL to obtain a dimethyldiallylammonium chloride solution with a concentration of 60%.

[0063] Example 1

[0064] Weigh 0.4 g of tussah silk gland and put it into a beaker, add 9 mL of Tris·HCl solution and 1 mL of SDS solution into the beaker, then put the beaker into a shaking incubator and shake it at a speed of 60 r / min for 2 h. After the shaking is completed, put the obtained feed liquid into a centrifuge tube and centrifuge it at 8000 r / min for 2 min to separate and remove insoluble matter, and collect the supernatant as the tussah silk gland protein solution (concentration is recorded as 4%);

[0065] The tussah silk gland protein solution is mixed with a sodium alginate solution with a concentration of 4%, and then allowed to stand for defoaming to obtain a raw material mixture, a calcium sulfate solution is used as a curing agent solution, and then a microfluidic spinning process is used to prepare tussah silk gland protein fibers. The steps of the microfluidic spinning process are as follows: the raw material mixture is extracted with a syringe, a rubber hose with a length of 20 cm is connected to one end of the injection port, a needle connector is installed at the other end, and a needle with a diameter of 0.5 mm is fixed; the injection volume specification is set to 10 mL and the injection speed is set to 5 mL / min on the microfluidic spinning machine; the needle fixed at the other end of the syringe is immersed in the curing agent solution, the microfluidic spinning machine is started, and the needle is moved at a uniform speed for spinning to ensure that uniform fibers can be spun; after the spinning is completed, the obtained fiber is continuously placed in the curing agent solution for curing for 15 minutes, and then the obtained fiber is taken out from the curing agent solution with tweezers, and dried at room temperature (naturally dried) to obtain tussah silk gland protein fibers.

[0066] The relevant conditions for preparing the tussah silk gland protein fibers in Example 1 are shown in Tables 1 to 3.

[0067] Table 1 Preparation conditions in Example 1 (fixed volume of curing agent solution)

[0068]

[0069]

[0070] Test Example 1

[0071] Figure 1The following are photos of fibers (before drying) obtained under different volume ratios of the tussah silk gland protein solution to the sodium alginate solution in Example 1, from left to right, the volume ratios of the tussah silk gland protein solution to the sodium alginate solution are 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, and 8:2. The results show that when the volume ratio of the tussah silk gland protein solution to the sodium alginate solution is 8:2, the obtained fiber morphology is smoother.

[0072] Figure 2 The following are photos of tussah silk gland protein fibers obtained by drying at room temperature under different volume ratios of tussah silk gland protein solution to sodium alginate solution in Example 1. From left to right, the volume ratios of tussah silk gland protein solution to sodium alginate solution are 3:7, 4:6, 5:5, 6:4, and 7:3. The results show that the mechanical properties and elasticity of the tussah silk gland protein fibers obtained when the volume ratio of tussah silk gland protein solution to sodium alginate solution is 5:5 are the best.

[0073] Example 2

[0074] According to the method of Example 1, tussah silk gland protein fiber was prepared by microfluid spinning process, wherein the curing agent solution used in this example was a calcium sulfate solution with a concentration of 0.07%, and the formula of the raw material mixture used was shown in Table 2, wherein the volume of the tussah silk gland protein solution (prepared by the same method as in Example 1) was 2 mL, and the concentration was 4%; the volume of the sodium alginate solution was 1.25 mL, and the concentration was 4%; the volume of the silver nitrate solution was 1 mL, and the concentrations were 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, and 1%, respectively; the volume of the borax solution was 1 mL, and the concentrations were 1%, 2%, 3%, 4%, and 5%, respectively.

[0075] Table 2 Raw material mixture formula in Example 2

[0076]

[0077]

[0078] Figure 3 This is a physical picture of the tussah silk gland protein fiber prepared in Example 2. Figure 3 A in the figure is a real picture of blank tussah silk gland protein fiber (i.e., without adding antibacterial agents silver nitrate and borax). The results show that it is light yellow in color, odorless, less flexible, fragile and easy to break. Figure 3B, C, D, E, F, G and H in the figure are actual pictures of antibacterial tussah silk gland protein fibers whose antibacterial agent is silver nitrate, wherein the concentrations of the silver nitrate solution used are 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9% and 1%, respectively; the results show that the fibers prepared after adding the silver nitrate solution are purple-red, and before drying at room temperature, the fibers are flexible and not easy to break, and have a tubular (columnar) structure; after drying at room temperature, the fibers feel hard and strong. Figure 3 I, J, H, K, L and M in the figure are the actual pictures of antibacterial tussah silk gland protein fiber with borax as the antibacterial agent, wherein the concentration of the borax solution used is 1%, 2%, 3%, 4% and 5% respectively; the results show that the fiber prepared after adding the borax solution is light yellow and uneven in shape, and the fiber is easy to break and difficult to fix before drying at room temperature; after drying at room temperature, the fiber is fragile and easy to break. In summary, the antibacterial tussah silk gland protein fiber made with silver nitrate is stronger and easier to shape than the antibacterial tussah silk gland protein fiber made with borax; from the perspective of preservation, the antibacterial tussah silk gland protein fiber made with silver nitrate is also easier to preserve.

[0079] Test Example 2

[0080] In this test example, the antibacterial property of the fiber is tested based on the inhibition zone. The specific steps are as follows:

[0081] Prepare nutrient broth: Place 15 g of tryptone, 5 g of plant peptone and 5 g of sodium chloride in a beaker, add distilled water to make up to 1000 mL, then seal the mouth of the beaker with aluminum foil and place it in a high-temperature sterilizer for high-temperature sterilization. After sterilization, place it on a sterile workbench, turn on the ultraviolet lamp, and sterilize for more than 20 minutes.

[0082] Bacterial culture: Use a measuring cylinder to take two 20mL portions of nutrient broth and pour them into conical flasks respectively. Take out Staphylococcus aureus and Escherichia coli from the refrigerator. Use a sampling stick to dip the two bacteria into the nutrient broth respectively. Seal the conical flask with aluminum foil and place it in a shaking incubator for 24 hours.

[0083] Prepare agar solution: put 10g of tryptone, 5g of yeast extract powder, 5g of sodium chloride and 15g of agar powder in a beaker, add 750mL of distilled water, then seal the beaker with aluminum foil and put it in a high-temperature sterilizer for high-temperature sterilization.

[0084] Bacterial dilution: Dilute the nutrient broth 20 times with distilled water and use it to adjust the bacterial concentration after culture to 1×10 8 CFU / mL~5×10 8 CFU / mL was used as the test bacterial solution, and the concentration of the bacterial solution was determined using a spectrophotometer.

[0085] Preparation of culture medium: Lower layer agar culture medium: prepare 11 plates, pour the agar solution into the plates, about 10 mL, repeat several times, let it stand, and wait for the agar to solidify; Upper layer culture medium: pour 10 mL of bacterial solution into the lower layer agar culture medium, let it stand, and wait for it to solidify.

[0086] Test: After the culture medium solidifies, take the prepared fiber sample to be tested, slowly place it in the middle of the culture medium, wait for 24 hours, and observe the experimental results.

[0087] Figure 4 This is a graph showing the antibacterial test results of the blank tussah silk gland protein fiber prepared in Example 2. The results show that no antibacterial zone is formed around the fiber.

[0088] Figure 5 These are the antibacterial (E. coli) test result graphs of the antibacterial tussah silk gland protein fiber prepared in Example 2, wherein A, B, and C are the antibacterial test result graphs of the antibacterial tussah silk gland protein fiber whose antibacterial agent is silver nitrate, and the concentrations of the silver nitrate solution are 0.4%, 0.5%, and 0.6% respectively; D, E, and F are the antibacterial test result graphs of the antibacterial tussah silk gland protein fiber whose antibacterial agent is borax, and the concentrations of the borax solution are 1%, 2%, and 3% respectively; the results show that the fiber prepared by adding borax solution has no obvious antibacterial effect on E. coli, and the lower the concentration, the less significant the antibacterial effect; the fiber prepared by adding silver nitrate solution has a better inhibitory effect on E. coli than borax.

[0089] Figure 6 These are the antibacterial (Staphylococcus aureus) test result graphs of the antibacterial tussah silk gland protein fiber prepared in Example 2, wherein A, B, C, and D are the antibacterial test result graphs of the antibacterial tussah silk gland protein fiber whose antibacterial agent is silver nitrate, and the concentrations of the silver nitrate solution are 0.7%, 0.8%, 0.9%, and 1% respectively; E and F are the antibacterial test result graphs of the antibacterial tussah silk gland protein fiber whose antibacterial agent is borax, and the concentrations of the borax solution are 4% and 5% respectively; the results show that the fibers prepared by adding silver nitrate solution or borax solution have significant inhibitory effects on Staphylococcus aureus, among which silver nitrate has better inhibitory effect. Similar to Escherichia coli, the higher the concentration of the antibacterial agent, the wider the inhibition zone formed and the better the antibacterial effect.

[0090] Example 3

[0091] The preparation method of the tussah silk gland protein solution used in this embodiment refers to the operation of Example 1, wherein the masses of the tussah silk glands used are 0.2g, 0.4g, 0.6g, 0.8g, and 1.0g, respectively, and the remaining operations are the same as Example 1. The concentrations of the final tussah silk gland protein solutions are recorded as 2%, 4%, 6%, 8%, and 10%, respectively; then, the tussah silk gland protein fibers are prepared by the microfluidic spinning process according to the method of Example 1.

[0092] The relevant conditions for preparing the tussah silk gland protein fibers in Example 3 are shown in Tables 3 to 6.

[0093] Table 3 Preparation conditions in Example 3 (different drug types)

[0094]

[0095] Table 4 Preparation conditions in Example 3 (solidifying agent solutions are all 0.1% calcium sulfate solutions)

[0096]

[0097] Table 5 Preparation conditions in Example 3 (different drug types and sodium alginate solution volumes)

[0098]

[0099]

[0100] Table 6 Preparation conditions in Example 3 (different concentrations of tussah silk gland protein solution)

[0101] Sample No. Type and amount of raw material mixture Type of curing agent solution C401# 10mL 2% Tussah silk gland protein solution + 6mL 3% sodium alginate solution 0.1% calcium sulfate solution C402# 10mL 4% tussah silk gland protein solution + 6mL 3% sodium alginate solution 0.1% calcium sulfate solution C403# 10mL 6% tussah silk gland protein solution + 6mL 3% sodium alginate solution 0.1% calcium sulfate solution C404# 10mL 8% Tussah silk gland protein solution + 6mL 3% sodium alginate solution 0.1% calcium sulfate solution C201# 10mL 10% tussah silk gland protein solution + 6mL 3% sodium alginate solution 0.1% calcium sulfate solution C405# 10mL 10% tussah silk gland protein solution + 4mL 3% sodium alginate solution 0.1% calcium sulfate solution

[0102] Comparative Example 1

[0103] The operation was carried out in accordance with the method of Example 3, except that the volume ratios of Tris·HCl solution and SDS solution used in preparing the tussah silk gland protein solution were 8:2 and 7:3, respectively; wherein the raw material mixture used in this comparative example was 10 mL of 10% tussah silk gland protein solution + 8 mL of 3% sodium alginate solution, and the curing agent solution used was 0.1% calcium sulfate solution; however, when spinning was carried out using the microfluidic spinning process under the above conditions, spinning was ultimately impossible.

[0104] Test Example 3

[0105] 3.1 Drug release test

[0106] Figure 7 This is a physical picture of the antibacterial tussah silk gland protein fiber containing different drugs in Example 3, wherein the left side is 10mL 10% tussah silk gland protein solution + 10mL 3% sodium alginate solution + 15mg dimethyl biguanide hydrochloride, and the right side is 10mL 10% tussah silk gland protein solution + 10mL 3% sodium alginate solution + 15mg bovine serum albumin, and the curing agent solutions used are all 0.1% calcium sulfate solutions; the results show that the addition of the two drugs has no obvious effect on the fiber formability, and the fibers are smooth and continuous.

[0107] 3.2 Antibacterial performance test

[0108] In this test example, LB liquid culture medium, LB agar culture medium, PDB liquid culture medium, and PDA liquid culture medium were prepared, and then culture media containing Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Candida albicans were prepared, respectively, and qualitative evaluation was performed based on the inhibition zone method.

[0109] Figure 8 This is the antibacterial performance test diagram of the antibacterial tussah silk gland protein fiber in Example 3 (Escherichia coli culture medium), wherein (a) is 10mL 10% tussah silk gland protein solution + 6mL 3% sodium alginate solution, (b) is 10mL 10% tussah silk gland protein solution + 10mL 3% sodium alginate solution + 15mg dimethyl biguanide hydrochloride, (c) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 20% bacitracin solution + 15mL 3% sodium alginate solution, (d) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 60% dimethyl diallyl ammonium chloride solution + 8mL 3% sodium alginate solution, and the curing agent solutions used are all 0.1% calcium sulfate solutions. The results showed that the antibacterial tussah silk gland protein fiber had a certain antibacterial effect on Escherichia coli.

[0110] Fig. 9 The antibacterial performance test diagram of the antibacterial tussah silk gland protein fiber in Example 3 (Staphylococcus aureus culture medium), wherein (a) is 10mL 10% tussah silk gland protein solution + 6mL 3% sodium alginate solution, (b) is 10mL 10% tussah silk gland protein solution + 10mL 3% sodium alginate solution + 15mg dimethyl biguanide hydrochloride, (c) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 20% bacitracin solution + 15mL 3% sodium alginate solution, (d) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 60% dimethyl diallyl ammonium chloride solution + 8mL 3% sodium alginate solution, and the used curing agent solution is 0.1% calcium sulfate solution. The results show that bacitracin has the best antibacterial performance on Staphylococcus aureus culture medium.

[0111] Fig.10The antibacterial performance test diagram of the antibacterial tussah silk gland protein fiber in Example 3 (Aspergillus niger culture medium), wherein (a) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 60% dimethyl diallyl ammonium chloride solution + 8mL 3% sodium alginate solution, (b) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 20% bacitracin solution + 15mL 3% sodium alginate solution, (c) is 5mL 10% tussah silk gland protein solution + 7.5mg bovine serum albumin + 5mL20% bacitracin solution + 15mL 3% sodium alginate solution, (d) is 5mL 10% tussah silk gland protein solution + 7.5mg bovine serum albumin + 5mL 10% bacitracin solution + 15mL 3% sodium alginate solution; the curing agent solution used was 0.1% calcium sulfate solution. The results showed that the antibacterial tussah silk gland protein fiber had a certain antibacterial effect on Aspergillus niger.

[0112] Fig.11 The antibacterial performance test diagram of the antibacterial tussah silk gland protein fiber in Example 3 (Candida albicans culture medium), wherein (a) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 60% dimethyl diallyl ammonium chloride solution + 8mL 3% sodium alginate solution, (b) is 5mL 10% tussah silk gland protein solution + 7.5mg dimethyl biguanide hydrochloride + 5mL 20% bacitracin solution + 15mL 3% sodium alginate solution, (c) is 5mL 10% tussah silk gland protein solution + 7.5mg bovine serum albumin + 5mL 20% bacitracin solution + 15mL 3% sodium alginate solution, and (d) is 5mL 10% tussah silk gland protein solution + 7.5mg bovine serum albumin + 5mL 10% bacitracin solution + 15mL 3% sodium alginate solution; the curing agent solution used was 0.1% calcium sulfate solution. The results showed that the antibacterial tussah silk gland protein fiber had a certain antibacterial effect on Candida albicans.

[0113] 3.3 Effect of different volume ratios of tussah silk gland protein solution and sodium alginate solution on the release performance of different drugs

[0114] Fig.12The test diagram of the effect of different volume ratios of tussah silk gland protein solution and sodium alginate solution on the release performance of different drugs in Example 3, wherein (a) is 10mL 10% tussah silk gland protein solution + 8mL 3% sodium alginate solution + 15mg dimethyl biguanide hydrochloride, (b) is 10mL 10% tussah silk gland protein solution + 12mL 3% sodium alginate solution + 15mg dimethyl biguanide hydrochloride, (c) is 10mL 10% tussah silk gland protein solution + 8mL 3% sodium alginate solution + 15mg bovine serum albumin; the curing agent solutions used are all 0.1% calcium sulfate solutions. The results show that different compounding volumes have no obvious effect on the fiber formability, and the fibers all show smooth continuity.

[0115] 3.4 Effects of different concentrations of tussah silk gland protein solutions on the properties of tussah silk gland protein fibers

[0116] Fig.13 The figure shows the effect of different concentrations of tussah silk gland protein solution on the performance of tussah silk gland protein fiber, where (a) is 10mL 2% tussah silk gland protein solution + 6mL 3% sodium alginate solution, (b) is 10mL 4% tussah silk gland protein solution + 6mL 3% sodium alginate solution, (c) is 10mL 6% tussah silk gland protein solution + 6mL 3% sodium alginate solution, (d) is 10mL 8% tussah silk gland protein solution + 6mL 3% sodium alginate solution; the curing agent solution used is 0.1% calcium sulfate solution. The results show that tussah silk gland protein fiber can still be successfully prepared when the concentration of tussah silk gland protein solution is changed.

[0117] In addition, experiments have found that changing the volume ratio of tussah silk gland protein solution to sodium alginate solution has little effect on the spinning process; and by intuitive hand touch, it can be found that when the volume ratio of tussah silk gland protein solution to sodium alginate solution is 5:2, the resulting tussah silk gland protein fiber is softer.

[0118] 3.5 Effect of stretching treatment on the mechanical properties of tussah silk gland protein fibers

[0119] Take 500 mL of 0.1% calcium sulfate solution and heat it to 35° C., put the tussah silk gland protein fiber into the heated 0.1% calcium sulfate solution, clamp the two ends of the tussah silk gland protein fiber with two tweezers respectively, and stretch it to 1.5 times of the original length.

[0120] Fig.14The following are the actual pictures of tussah silk gland protein fibers after stretching treatment, where (a) is 10mL 10% tussah silk gland protein solution + 10mL 3% sodium alginate solution + 15mg dimethyl biguanide hydrochloride, and (b) is 10mL 10% tussah silk gland protein solution + 10mL 3% sodium alginate solution + 15mg bovine serum albumin; the curing agent solutions used are all 0.1% calcium sulfate solutions. The results show that after the tussah silk gland protein fibers are stretched, the tussah silk gland protein fibers become thinner and still present a good fiber morphology.

[0121] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing tussah silk gland protein fiber, comprising the following steps: Providing a raw material mixture, the raw material mixture comprising a tussah silk gland protein solution and a sodium alginate solution, the tussah silk gland protein solution comprising tussah silk gland protein, a Tris·HCl solution and a sodium dodecyl sulfate solution, the concentration of Tris·HCl in the Tris·HCl solution being 0.01 to 0.012 g / mL, the concentration of the sodium dodecyl sulfate solution being 0.05 to 0.1 g / mL, the volume ratio of the Tris·HCl solution to the sodium dodecyl sulfate solution being 7 to 9:1, and the concentration of the sodium alginate solution being 0.03 to 0.04 g / mL; In the presence of a curing agent solution, the raw material mixture is spun to obtain the tussah silk gland protein fiber.

2. The preparation method according to claim 1, characterized in that: The pH value of the Tris·HCl solution is 8-12.

3. The preparation method according to claim 1 or 2, characterized in that: The concentration of tussah silk gland protein in the tussah silk gland protein solution is 0.01-0.05 g / mL; the concentration of the sodium alginate solution is 0.01-0.08 g / mL; and the volume ratio of the tussah silk gland protein solution to the sodium alginate solution is 5:5-9:

1.

4. The preparation method according to claim 1, characterized in that: The curing agent in the curing agent solution includes calcium sulfate; and the concentration of the curing agent in the curing agent solution is 0.5-2 mg / mL.

5. Tussah silk gland protein fiber prepared by the preparation method according to any one of claims 1 to 4.

6. Use of the tussah silk gland protein fiber according to claim 5 in preparing a drug carrier.

7. A drug-loaded tussah silk gland protein fiber, comprising the tussah silk gland protein fiber according to claim 5 and a drug loaded on the tussah silk gland protein fiber.

8. The drug-loaded tussah silk gland protein fiber according to claim 7, characterized in that: The drugs include antibacterial drugs.

9. The drug-loaded tussah silk gland protein fiber according to claim 8, characterized in that: The antibacterial drug is an organic antibacterial drug and / or an inorganic antibacterial drug.

10. The drug-loaded tussah silk gland protein fiber according to claim 9, characterized in that: The organic antibacterial drug includes one or more of bacitracin, dimethylbiguanide hydrochloride and bovine serum albumin; the inorganic antibacterial drug includes one or more of silver nitrate, borax and dimethyldiallylammonium chloride.

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