阅读说明：本技术 一种超薄透明丝素蛋白膜、制备方法及应用 (Ultrathin transparent silk fibroin film, preparation method and application ) 是由 汪涛 李飞 陈文浩 于 2020-07-02 设计创作，主要内容包括：本发明公开了一种超薄透明丝素蛋白膜、制备方法及应用。该丝素蛋白膜表面光滑无孔,成膜厚度可控,为0.5-2μm,膜的透光率在可见光范围内超过90%。具体的制备方法是将丝素纤维或粉体溶解于含少量LiBr的有机溶剂中,得到高浓度的丝素蛋白液,然后将丝素蛋白液稀释过滤后,缓慢注入聚乙二醇溶液液面上,丝素蛋白液迅速在液-气界面扩散并固化成膜,再经纯水清洗、干燥后得到超薄透明丝素蛋白膜。本发明的制备方法简单高效,丝素蛋白膜厚度薄、透明度高,可应用于细胞培养支架、生物活性界面和柔性透明电子材料等方面。(The invention discloses an ultrathin transparent silk fibroin film, a preparation method and application. The silk fibroin membrane has smooth and non-porous surface, controllable membrane forming thickness of 0.5-2 mu m, and light transmittance of over 90% in a visible light range. The specific preparation method comprises the steps of dissolving the silk fibroin fibers or the powder in an organic solvent containing a small amount of LiBr to obtain a high-concentration silk fibroin solution, diluting and filtering the silk fibroin solution, slowly injecting the diluted and filtered silk fibroin solution onto the liquid surface of a polyethylene glycol solution, quickly diffusing the silk fibroin solution on a liquid-gas interface, curing the solution to form a film, and cleaning and drying the film by pure water to obtain the ultrathin transparent silk fibroin film. The preparation method is simple and efficient, and the silk fibroin film is thin and high in transparency, and can be applied to cell culture scaffolds, bioactive interfaces, flexible transparent electronic materials and the like.)

1. An ultrathin transparent silk fibroin film is characterized in that: the silk fibroin film is smooth and non-porous, the thickness of the silk fibroin film is 0.5-2 mu m, and the light transmittance of the film exceeds 90% in a visible light range.

2. A method of preparing the ultra-thin transparent silk fibroin film of claim 1, comprising:

s1, dissolving silk fibroin fibers or powder in an organic solvent containing LiBr, wherein the organic solvent is methanol or acetone, so as to obtain a high-concentration silk fibroin solution;

s2, diluting the silk fibroin solution obtained in the step S1 to a concentration of 15-25%, and centrifugally filtering the diluted silk fibroin solution;

s3, injecting the silk fibroin solution obtained in the step S2 into the surface of a glycol solution, and quickly spreading and curing to form a film;

and S4, removing the silk fibroin film obtained in the step S3, soaking and cleaning the silk fibroin film by pure water, then coiling and drying to obtain the ultrathin transparent silk fibroin film.

3. The method for preparing the ultrathin transparent silk fibroin film as claimed in claim 2, is characterized in that: in the step S1, the concentration of LiBr is 5-8 wt%, and the concentration of the silk fibroin liquid is 30-40%.

4. The method for preparing the ultrathin transparent silk fibroin film as claimed in claim 2, is characterized in that: the diluting solvent used in the step S2 is one or more of water, methanol or acetone.

5. The method for preparing the ultrathin transparent silk fibroin film as claimed in claim 2, is characterized in that: the glycol solution in the step S3 is polyethylene glycol 200 with the concentration of 80-100%.

6. The method for preparing the ultrathin transparent silk fibroin film as claimed in claim 2, is characterized in that: in the step S3, the injection height of the fibroin protein solution is 1-20 mm above the liquid level of the polyethylene glycol 200 solution.

7. The method for preparing the ultrathin transparent silk fibroin film as claimed in claim 2, is characterized in that: the curing time of the film in the step S3 is 2-30 min.

8. The method for preparing the ultrathin transparent silk fibroin film as claimed in claim 2, is characterized in that: in the step S4, the drying temperature is 25-50 ℃.

9. The use of an ultra-thin transparent silk fibroin film as claimed in claims 1 and 2, characterized by its application to cell culture scaffolds, bioactive interfaces and flexible transparent electronic materials.

Technical Field

The invention relates to a natural polymer membrane material, in particular to an ultrathin transparent silk fibroin membrane, a preparation method and application, belonging to the field of natural polymer materials.

Background

Silk fibroin is a natural polymer with excellent biocompatibility, mechanical properties, and optical properties. The silk fibroin solution is obtained after dissolving the silk fibroin fibers, and then the silk fibroin solution is prepared into a silk fibroin film, so that the silk fibroin film has wide research and application in the aspects of biomedical materials, biological optoelectronic materials, flexible display devices and the like. The 2010 publication of Nature Materials at 96 th phase 511-517 is named as "Dissolvable films of silk fibroin for ultra-thin biocompatible electronics", and the silk fibroin film is dried by casting to prepare a thicker silk fibroin film-supported conductive layer, and then the silk fibroin film is partially dissolved to obtain an ultrathin conductive film, which is applied to a brain tissue conformal integrated circuit. 2011 23 nd 1630 th page 1634 of Advanced Materials, entitled "Flexible Organic Thin-Film Transistors with Silk fibers as the Gate Dielectric", soaks a PET Film in a 2% Fibroin solution and then dries to form a Fibroin Film insulated Gate. A review of the development of Flexible electronics using Silk Fibroin films was made by the name "Silk fiber for Flexible Electronic Devices" published by 2016, Advanced Materials, No. 28, 4250-4265. Chinese patent of invention with publication number CN103861149A, a durable transparent silk fibroin film and a preparation method thereof, mixes a silk fibroin solution and micromolecular amide and then dries the mixture into a film, the light transmittance of the film is more than 90%, and the film can be used for artificial cornea. Chinese patent publication No. CN101879098A "artificial eardrum using silk protein and method for manufacturing the same" applies silk solution to artificial eardrum by drying membrane. The invention patent of China with publication number CN103361885A discloses a method for preparing an antibacterial silk fibroin fiber membrane, which comprises mixing nano silver into a silk fibroin solution, and preparing the antibacterial silk fibroin fiber membrane by an electrostatic spinning method, and can be used in the field of biomedicine.

However, the existing silk fibroin membrane preparation methods are mainly a solution drying method, an electrostatic spinning method and the like, and have the problems of complicated process conditions, long consumed time, poor membrane uniformity, difficulty in controlling membrane thickness and the like, so that the improvement of the silk fibroin membrane preparation method and the improvement of the structural performance of the silk fibroin membrane have important significance. In recent years, a liquid surface-based rapid film forming technology attracts attention of researchers, and the method has the advantages of high film forming speed, low cost, thin and controllable film thickness and popularization and application.

Disclosure of Invention

One of the purposes of the invention is to provide an ultrathin transparent silk fibroin film, which is ultrathin and soft, has a smooth and nonporous film surface, has the light transmittance of over 90 percent in a visible light range, has good mechanical property and biocompatibility, and has good application prospect in the aspects of cell culture scaffolds, bioactive interfaces, flexible transparent electronic materials and the like.

The invention also aims to provide a preparation method of the ultrathin transparent silk fibroin film, which mainly dissolves silk fibroin by a low-concentration LiBr organic solvent system to obtain high-concentration silk fibroin liquid, and then quickly diffuses the silk fibroin liquid on a liquid-gas interface of an organic solution to form a film by utilizing an interface diffusion principle, wherein the method is simple, convenient and efficient, and the thickness of the silk fibroin film is adjustable and controllable, and comprises the following steps:

s1, dissolving silk fibroin fibers or powder in an organic solvent containing LiBr, wherein the organic solvent is methanol or acetone, so as to obtain a high-concentration silk fibroin solution;

s2, diluting the silk fibroin solution obtained in the step S1 to a concentration of 15-25%, and centrifugally filtering the diluted silk fibroin solution;

s3, injecting the silk fibroin solution obtained in the step S2 into the surface of a glycol solution, and quickly spreading to form a film and solidifying;

and S4, removing the silk fibroin film obtained in the step S3, soaking and cleaning the silk fibroin film by pure water, then coiling and drying to obtain the ultrathin transparent silk fibroin film.

Preferably, in the step S1, the concentration of LiBr is 5-8%, and the concentration of the silk fibroin liquid is 30-40%.

Preferably, the dilution solvent in step S2 is one or more of water, methanol, and acetone.

Preferably, the glycol solution in the step S3 is polyethylene glycol 200 with a concentration of 80-100%.

Preferably, the injection height of the silk fibroin solution in the step S3 is 1-20 mm above the glycol solution.

Preferably, the curing time of the film in step S3 is 2-30 min.

Preferably, the drying temperature of the silk fibroin film in the step S4 is 25-50 ℃.

The ultrathin transparent silk fibroin film can be applied to cell culture scaffolds, bioactive interfaces and flexible transparent electronic materials.

The invention has the beneficial effects that: the silk fibroin film structure of the invention is different from electrostatic spinning fiber films and solution drying films, and the film has the advantages of ultra-thin, softness, high light transmittance and the like, and has good mechanical property and biocompatibility. The preparation method of the invention utilizes the principle of interface diffusion to enable the silk fibroin liquid to be rapidly diffused and formed into a film on the liquid-gas interface of the organic solution, compared with an electrostatic spinning method and a solution drying method, the preparation method has the advantages of simple and efficient process and high film forming quality, and can carry out structure regulation and control on the film.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

fig. 1 is an optical picture and surface SEM image of the silk fibroin membrane of example 2;

fig. 2 is a graph of light transmittance of the silk fibroin film of example 1.

Detailed Description

The present invention will be described in further detail with reference to the following drawings and examples, but the present invention is not limited thereto.