阅读说明：本技术 一种丝素蛋白与聚乙烯醇的复合水凝胶及其制备方法和应用 (Composite hydrogel of silk fibroin and polyvinyl alcohol, and preparation method and application thereof ) 是由 汪宜宇 李祥 牛春青 王欣宇 戴余军 张俊华 于 2019-09-30 设计创作，主要内容包括：本发明一种丝素蛋白与聚乙烯醇的复合水凝胶及其制备方法,可在短时间内形成水凝胶,而且可有效提高材料的亲水性和凝胶强度,并且在药物缓释应用领域,该水凝胶能够利用聚乙烯醇的分散助溶的作用,负载水凝胶难以负载的疏水性药物,扩展了其作为药物载体的应用范围。本发明还包括以丹皮酚作为疏水性药物模型,丝素蛋白与聚乙烯醇复合凝胶作为药物载体,使丹皮酚以一定的速率缓慢释放,有利于提高药物在治疗部位的滞留时间,使药物浓度在较长时间内保持有效治疗浓度范围,提高生物利用度,达到药物缓释的目的。(The silk fibroin and polyvinyl alcohol composite hydrogel and the preparation method thereof can form hydrogel in a short time, effectively improve the hydrophilicity and the gel strength of the material, and in the field of drug sustained release application, the hydrogel can utilize the dispersing and dissolving-assisting effect of the polyvinyl alcohol to load hydrophobic drugs which are difficult to load, thereby expanding the application range of the hydrogel as drug carriers. The invention also comprises the application of paeonol as a hydrophobic drug model, and silk fibroin and polyvinyl alcohol composite gel as a drug carrier, so that the paeonol is slowly released at a certain speed, the retention time of the drug at a treatment part is favorably prolonged, the drug concentration is kept in an effective treatment concentration range for a long time, the bioavailability is improved, and the purpose of drug sustained release is achieved.)

1. A preparation method of composite hydrogel of silk fibroin and polyvinyl alcohol is characterized by comprising the following steps:

1) preparation of silk fibroin: adding anhydrous sodium carbonate into boiling water to obtain an anhydrous sodium carbonate aqueous solution, placing silk into the anhydrous sodium carbonate aqueous solution for degumming, separating the obtained solid, drying, dissolving with a ternary solution or a lithium bromide aqueous solution, placing the obtained solution into a dialysis bag, then placing the dialysis bag into deionized water for dialysis for 48-96h, and obtaining a silk fibroin aqueous solution after dialysis;

2) Preparation of aqueous polyvinyl alcohol solution: weighing polyvinyl alcohol, adding the polyvinyl alcohol into deionized water, and stirring in a water bath until the polyvinyl alcohol is completely dissolved to obtain a polyvinyl alcohol solution;

3) Preparing the composite hydrogel of silk fibroin and polyvinyl alcohol: mixing the silk fibroin aqueous solution obtained in the step 1) with the polyvinyl alcohol solution obtained in the step 2), uniformly mixing, and then sequentially adding horseradish peroxidase and hydrogen peroxide for crosslinking to finally obtain the silk fibroin and polyvinyl alcohol composite hydrogel.

2. The method for preparing the composite hydrogel of silk fibroin and polyvinyl alcohol according to claim 1, which is characterized in that: the concentration of the anhydrous sodium carbonate aqueous solution obtained in the step 1) is 0.05-0.08 wt%, deionized water is replaced every 2h during dialysis, and the concentration of the silk fibroin aqueous solution finally obtained is 8 wt%; the ternary solution in the step 1) consists of CaCl2, ethanol and water, wherein the mass ratio of CaCl2 to the ethanol to the water is 1:2: 8; the concentration of the lithium bromide salt solution is 9.3 mol/L.

3. The method for preparing the composite hydrogel of silk fibroin and polyvinyl alcohol according to claim 1, which is characterized in that: in the step 2), the weight percentage of the polyvinyl alcohol aqueous solution is 6-10%, and the water bath temperature is 90 ℃.

4. The method for preparing the composite hydrogel of silk fibroin and polyvinyl alcohol according to claim 2, which is characterized in that: and 3) mixing the silk fibroin aqueous solution and the polyvinyl alcohol solution in equal volume, wherein the cross-linking temperature is that the reaction temperature is 20-40 ℃, the concentration of horseradish peroxidase in the final system is 10U/ml, and the concentration of hydrogen peroxide is 0.05-20 mg/ml.

5. The method for preparing the composite hydrogel of silk fibroin and polyvinyl alcohol according to any one of claims 1-4, wherein in the step 2), the method further comprises the following steps: after the polyvinyl alcohol solution is obtained, paeonol is weighed and dissolved in the polyvinyl alcohol solution by stirring in a water bath.

6. The method for preparing the composite hydrogel of silk fibroin and polyvinyl alcohol according to claim 5, wherein the method comprises the following steps: the water bath temperature for dissolving paeonol is 40 deg.C, and the concentration of paeonol in polyvinyl alcohol solution is 0-4 mg/ml.

7. a composite hydrogel of silk fibroin and polyvinyl alcohol is characterized in that: the silk fibroin-polyvinyl alcohol hydrogel is prepared by adopting the preparation method of the silk fibroin-polyvinyl alcohol composite hydrogel as claimed in any one of claims 1 to 6.

Technical Field

The invention belongs to the technical field of hydrogel, and particularly relates to composite hydrogel of silk fibroin and polyvinyl alcohol, and a preparation method and application thereof.

Background

The silk is one of the earliest utilized natural proteins of human beings, is used as a natural fiber with excellent performance, and is mainly applied to the textile industry. Silk is composed of silk fibroin and sericin, and silk fibroin accounts for about 75% of the total weight. The amino acid composition of the silk fibroin is mainly glycine, alanine and serine, is similar to the composition of collagen amino acid of a human body, has good biocompatibility, and can be used for preparing materials in various forms such as films, gels, microcapsules and the like, wherein the silk fibroin hydrogel has wide application prospects in the fields of drug carriers, biomedical materials and tissue engineering. However, the simple silk fibroin hydrogel has poor mechanical properties and swelling properties, so that the application range of the silk fibroin hydrogel in the biomedical field is limited.

Polyvinyl alcohol (PVA) is a water-soluble polymer obtained by alcoholysis of polyvinyl acetate. The polyvinyl alcohol has excellent performances of film forming property, tensile resistance, flexibility, adhesion, water solubility, water absorption and the like. The transdermal drug delivery system using polyvinyl alcohol gel as a carrier has high water content, good coupling property with the skin surface, no skin discomfort, sustained release, thickening and stabilizing effects, and wide application in the field of biological materials.

paeonol (Paeonol), also called Paeonol, is an effective component extracted from root bark of Paeonia suffruticosa of Paeonia of Ranunculaceae and dried root or whole plant of Cynanchum paniculatum of Asclepiadaceae, and is a hydrophobic drug with poor water solubility. It has good pharmacological activity in the aspects of antibiosis and antiphlogosis, antipyresis and analgesia, anti-tumor, antianaphylaxis and the like.

Disclosure of Invention

the hydrogel formed by compounding the polyvinyl alcohol and the silk fibroin provided by the invention can be formed in a short time, the hydrophilicity and the gel strength of the material can be effectively improved, and in the field of drug slow release application, the hydrogel can load hydrophobic drugs which are difficult to load by using the dispersion and dissolution-assisting effect of the polyvinyl alcohol, so that the application range of the hydrogel as a drug carrier is expanded. The invention takes paeonol as a hydrophobic drug model, and takes the silk fibroin and polyvinyl alcohol composite gel as a drug carrier, so that the paeonol is slowly released at a certain speed, the detention time of the drug at a treatment part is favorably prolonged, the drug concentration is kept in an effective treatment concentration range for a longer time, the bioavailability is improved, and the purpose of drug slow release is achieved.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a preparation method of composite hydrogel of silk fibroin and polyvinyl alcohol comprises the following steps:

1) Preparation of silk fibroin: adding anhydrous sodium carbonate into boiling water to obtain an anhydrous sodium carbonate aqueous solution, placing silk into the anhydrous sodium carbonate aqueous solution for degumming, separating the obtained solid, drying, dissolving with a ternary solution or a lithium bromide aqueous solution, placing the obtained solution into a dialysis bag, then placing the dialysis bag into deionized water for dialysis for 48-96h, and obtaining a silk fibroin aqueous solution after dialysis;

2) Preparation of aqueous polyvinyl alcohol solution: weighing polyvinyl alcohol (molecular weight is 31000) and adding into deionized water, stirring in water bath until completely dissolving to obtain polyvinyl alcohol solution;

3) Preparing the composite hydrogel of silk fibroin and polyvinyl alcohol: mixing the silk fibroin aqueous solution obtained in the step 1) with the polyvinyl alcohol solution obtained in the step 2), uniformly mixing, and then sequentially adding horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) for crosslinking to finally obtain the silk fibroin and polyvinyl alcohol composite hydrogel.

On the basis of the technical scheme, the invention can further have the following specific selection or optimized selection.

Specifically, the concentration of the anhydrous sodium carbonate aqueous solution obtained in the step 1) is 0.05-0.08 wt% (preferably 0.08 wt%), deionized water is replaced every 2h during dialysis, and the concentration of the finally prepared silk fibroin aqueous solution is 8 wt%; the ternary solution in the step 1) consists of CaCl2, ethanol and water, wherein the mass ratio of CaCl2 to the ethanol to the water is 1:2: 8; the concentration of the lithium bromide salt solution is 9.3 mol/L. Under the condition, the silk fibroin aqueous solution with high purity can be obtained by purification from natural silk.

Specifically, the concentration of the polyvinyl alcohol aqueous solution in the step 2) is 6-10 wt%, and the water bath temperature is 90 ℃.

Specifically, the silk fibroin aqueous solution and the polyvinyl alcohol solution in the step 3) are mixed in equal volume, the cross-linking temperature is 20-40 ℃, the concentration of horseradish peroxidase in the final system is 10U/ml, and the concentration of hydrogen peroxide is 0.05-20 mg/ml.

In addition, the invention also provides the composite hydrogel of the silk fibroin and the polyvinyl alcohol prepared by the method. The conventional preparation method of the silk fibroin hydrogel generally has the problem of long gel time, the hydrophilicity of the silk fibroin hydrogel needs to be improved, and the silk fibroin hydrogel serving as a drug carrier is difficult to load hydrophobic drugs. Therefore, the invention provides a preparation method of the composite hydrogel of silk fibroin and polyvinyl alcohol, the method has short gelation time, and the obtained composite hydrogel has better water absorption, regular pore structure and better slow release effect on hydrophobic drugs.

in addition, the invention also provides an application of the silk fibroin and polyvinyl alcohol composite hydrogel, which comprises the following steps:

1) Preparation of silk fibroin: adding anhydrous sodium carbonate into a boiling water solution to obtain an anhydrous sodium carbonate aqueous solution, placing silk into the anhydrous sodium carbonate aqueous solution for degumming, separating the obtained solid, drying, dissolving with a ternary solution or a lithium bromide solution, placing the obtained solution into a dialysis bag, then placing the dialysis bag into deionized water for dialysis for 48-96h, and obtaining a silk fibroin aqueous solution after dialysis;

2) Preparation of aqueous polyvinyl alcohol solution: weighing polyvinyl alcohol (molecular weight is 31000) and adding into deionized water, stirring in water bath until completely dissolving to obtain polyvinyl alcohol solution;

3) preparing a paeonol polyvinyl alcohol solution: weighing paeonol, stirring in a water bath, and dissolving into the polyvinyl alcohol solution obtained in the step 2) to obtain a paeonol polyvinyl alcohol solution;

4) Preparing the composite hydrogel of silk fibroin and polyvinyl alcohol: mixing the silk fibroin aqueous solution obtained in the step 1) with the paeonol polyvinyl alcohol solution obtained in the step 3), uniformly mixing, and then sequentially adding horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) for crosslinking to finally obtain the paeonol-loaded silk fibroin and polyvinyl alcohol composite hydrogel.

Specifically, the concentration of the anhydrous sodium carbonate aqueous solution obtained in the step 1) is 0.05-0.08 wt%, deionized water is replaced every 2h during dialysis, and the concentration of the finally prepared silk fibroin aqueous solution is 8 wt%; the ternary solution in the step 1) consists of CaCl2, ethanol and water, wherein the mass ratio of CaCl2 to the ethanol to the water is 1:2: 8; the concentration of the lithium bromide salt solution is 9.3 mol/L. Under the condition, the silk fibroin aqueous solution with high purity can be obtained by purification from natural silk.

specifically, the concentration of the polyvinyl alcohol aqueous solution in the step 2) is 6-10 wt%, the water bath temperature is 90 ℃, the water bath temperature in the step 3) is 40 ℃, and the concentration of paeonol in the paeonol polyvinyl alcohol solution is 0-4 mg/ml.

Specifically, the silk fibroin aqueous solution and the polyvinyl alcohol solution in the step 4) are mixed in equal volume, the cross-linking temperature is 20-40 ℃, the concentration of horseradish peroxidase in a final system is 10U/ml, and the concentration of hydrogen peroxide is 0.05-20 mg/ml.

In addition, the invention also provides the paeonol-containing silk fibroin and polyvinyl alcohol composite hydrogel obtained by the method.

Compared with the prior art, the invention has the beneficial effects that: the composite silk fibroin and polyvinyl alcohol aqueous solution in the invention can quickly form gel under the enzymatic action, the material forming method is simple and quick, no toxic or side effect exists, and the prepared hydrogel has good hydrophilicity and a regular porous structure. Meanwhile, the hydrogel can be loaded with a hydrophobic drug paeonol, and has a good drug slow-release effect. Solves the problem that the hydrophobic drugs such as paeonol are difficult to dissolve and disperse in the hydrogel. The composite hydrogel provided by the invention effectively utilizes the advantages of the two, improves the performance of single-component hydrogel, and can be widely used in the field of biomedical materials such as drug carriers.

Drawings

FIG. 1 is a diagram of a gel in example 2, wherein A is a polyvinyl alcohol aqueous solution with a concentration of 8 wt%, B is a polyvinyl alcohol and silk fibroin blending solution, C is a polyvinyl alcohol and silk fibroin blending solution to which horseradish peroxidase and hydrogen peroxide are added, and D is a silk fibroin and polyvinyl alcohol composite hydrogel;

FIG. 2 is a SEM image of examples 1-4 and comparative examples, wherein A is example 1, B is example 2, C is example 3, D is example 4, and E is comparative example;

Fig. 3 is a slow release curve of paeonol in the paeonol-containing silk fibroin and polyvinyl alcohol composite hydrogel obtained in example 4.

Detailed Description

For a better understanding of the present invention, the following further illustrates the present invention with reference to the accompanying drawings and specific examples, but the present invention is not limited to the following examples.