CN115128839A - Method for preparing silk fibroin contact lenses based on natural silk - Google Patents

Abstract

The invention discloses a method for preparing a silk fibroin contact lens based on natural silk. The method comprises the following steps: degumming the natural silk from a potassium hydroxide solution and then dissolving it with lithium bromide to obtain a silk fibroin solution; dialyzing the silk fibroin solution with propylene After the amide is mixed, it is dropped into the contact lens mold and air-dried to obtain the lens; it solves the problem of poor air permeability of the prior art contact lens, long-term wearing will lead to corneal hypoxia, redness, pain, dryness and even vision loss. question.

Description

A kind of method for preparing silk fibroin contact lens based on natural silk

technical field

The invention belongs to the technical field of contact lenses, in particular to a method for preparing silk fibroin contact lenses based on natural silk.

Background technique

Contact lenses, also known as contact lenses, are tools worn on the cornea of the eye to correct and protect vision. Contact lenses provide a wide field of vision and realistic vision, which can help control the development of myopia and astigmatism in teenagers, and some of them also have the effect of treating and preventing eye diseases. Contact lenses can help myopic patients get rid of the shackles of frame glasses, and have the role of cosmetic decoration, so they are sought after by many young people. However, the current basic materials of contact lenses are still mainly polymer hydrogels and silicone hydrogels. This results in the material of the contact lens being a threat to the environment. In addition, many contact lenses have poor air permeability, and long-term wearing can lead to hypoxia in the cornea, causing redness, pain, dryness and even vision loss in the eyes.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is: to provide a method for preparing silk fibroin contact lenses based on natural silk, so as to solve the poor air permeability of the prior art contact lenses, and long-term wearing will lead to hypoxia of the cornea, causing redness and pain in the eyes , dryness or even decreased vision and other technical problems.

The technical scheme of the present invention is:

A method for preparing a silk fibroin contact lens based on natural silk. The method comprises the following steps: degumming the natural silk from a potassium hydroxide solution and dissolving it with lithium bromide to obtain a silk fibroin solution; dialyzing the silk fibroin solution and mixing it with acrylamide. Dropped into contact lens molds and air-dried to obtain lenses.

The lens is the reaction product of lithium bromide, acrylamide and silk fibroin.

The silk protein solution was dialyzed in sterile ultrapure water for 4 to 6 days, and the sterile ultrapure water was replaced every 6 to 24 hours.

The contact lens mold is washed and dried with sterile water, and then a mixed solution of acrylamide and silk fibroin is added; the temperature of the air-drying process is 10-40 ^° C.

The potassium hydroxide solution is 0.3%~3% (w/v), the concentration of the lithium bromide solution is 1%~10% (g/mL), and the concentration of the acrylamide solution is 2.5%~7.5% (g/mL) mL); the acrylamide solution and the silk protein solution were mixed in a volume ratio of 1:10.

The silk protein solution is a solution obtained by mixing natural silk with a lithium bromide solution after degumming. The preparation method is as follows: after removing impurities from the silk, put it into an alkaline solution to remove the glue, and then mix and stir with the lithium bromide solution to break the hydrogen bond network in the silk fiber. , so as to dissolve the silk fibroin into a silk protein solution and reprocess it, and then remove the lithium bromide and soluble impurities contained in the silk protein solution by dialysis.

The lens is a silk fibroin film induced by acrylamide molecules. The preparation method is as follows: blending acrylamide molecules with a silk protein solution, inducing the amorphous structure of silk fibroin to form a crystalline and stable silk fibroin film, and then repeatedly soaking and rinsing. Remove acrylamide.

The concentration of silk protein is 5%~15%, and the concentration of acrylamide is 2.5%~7.5%; the temperature range of acrylamide molecule-induced silk fibroin film formation is 10~40 ^o C; the humidity of acrylamide molecule-induced silk fibroin film formation The range is 10%~50%.

Beneficial effects of the present invention:

The silk fibroin contact lens prepared based on natural silk provided by the invention is a solution obtained by mixing the natural silk with a lithium bromide solution after degumming. The preparation method is as follows: after removing obvious impurities from the silk, put alkali Remove the glue from the solution, then mix and stir with the lithium bromide solution to break the hydrogen bond network in the silk fiber, so as to dissolve the silk fibroin into a silk protein solution and reprocess it, and then remove the lithium bromide and other soluble substances contained in the silk protein solution by dialysis. impurities. The silk fibroin lens is a silk fibroin film induced by acrylamide molecules, and the preparation method is as follows: blending acrylamide molecules with a silk fibroin solution to induce an amorphous structure of silk fibroin to form a crystalline and stable silk fibroin film, The acrylamide is then removed by repeated soaking and rinsing. The silk fibroin lens endows the contact lens with the function of high oxygen permeability.

The main ingredients of the silk fibroin contact lenses provided by the invention and their effects are as follows:

Silk: A natural fiber that has a long history of making silk threads, woven ribbons, and simple silk fabrics. As a natural source, silk has the effect of skin metabolism, can effectively resist mites and bacteria, and will not cause skin allergies. It is often used in the field of beauty. Silk is rich in high molecular silk fibroin, accounting for about 70% to 80% of silk. Can be used as a natural source of silk fibroin.

Silk fibroin: An excellent natural polymer fibrin has been widely used in the field of biomedical materials. As a natural biomaterial, silk fibroin possesses many remarkable properties, such as: good biocompatibility, suitable mechanical properties, low immunity and controllable degradation rate. Multiscale structures from water-soluble to water-insoluble can be achieved. At present, silk protein scaffolds have been widely used in a variety of tissue engineering, including the repair of cartilage, nerves, blood vessels, etc. In addition, its reliable source and easy access are also a major advantage of its wide application.

Lithium Bromide: An inorganic substance that is very soluble in water. It is an efficient water vapor absorbent and air humidity regulator and can be used as absorption refrigerant, hydrogen chloride remover in organic chemistry, and fiber bulking agent. The hydrogen bond network within the silk fiber can be broken, thereby dissolving the silk fibroin into a silk protein solution and reprocessing.

Acrylamide: used as a raw material for organic synthesis and a raw material for polymer materials. It is usually soluble in water, especially for the flocculation of protein and starch in water. It has excellent properties such as flocculation, thickening, shear resistance, resistance reduction and dispersibility.

To sum up, the silk fibroin contact lens provided by the present invention has at least the following beneficial effects:

High safety : The silk fibroin used to prepare the lenses comes from nature, has good biocompatibility, and is safe for the human body. The porous structure of the lens makes it highly oxygen permeable, which can avoid eye redness and pain caused by corneal hypoxia, and protect the wearer's eye health.

Environmental protection : The silk fibroin that constitutes the lens can be degraded in the natural environment without pollution to the environment.

The technical problems such as poor air permeability of the prior art contact lenses, and long-term wearing of the contact lenses will lead to hypoxia of the cornea, causing redness, pain, dryness and even decreased vision in the eyes.

Description of drawings

Fig. 1 is the preparation flow chart of the silk fibroin contact lens in one embodiment of the present invention;

FIG. 2 is a schematic longitudinal cross-sectional view of a silk fibroin contact lens in an embodiment of the present invention.

Detailed ways

The present invention adopts the following technical scheme: natural silk is degummed by potassium hydroxide solution and then dissolved by lithium bromide to obtain a silk protein solution; after dialysis, the silk protein solution is mixed with acrylamide and then dropped into a contact lens mold, and air-dried to obtain a lens.

As shown in Figure 1, the preparation process includes the following main steps: after the natural silk is degummed, it is dissolved by lithium bromide to obtain a silk protein solution; after the silk protein solution is dialyzed and cleaned, it is mixed with acrylamide and then dropped into a contact lens mold, Air-dry to obtain lenses.

Preferably, the lens is a reaction product of lithium bromide, acrylamide, and silk fibroin.

Preferably, the silk protein solution is dialyzed in sterile ultrapure water for 4 to 6 days, and the sterile ultrapure water is replaced every 6 to 24 hours.

Preferably, the contact lens mold is washed and dried with sterile water, and then a mixed solution of acrylamide and silk fibroin is added; the temperature of the air-drying process is 10-40 ^° C.

Preferably, the potassium hydroxide solution is 0.3%~3% (w/v), the concentration of the lithium bromide solution is 1%~10% (g/mL), and the concentration of the acrylamide solution is 2.5%~ 7.5% (g/mL); the acrylamide solution and the silk protein solution were mixed at a volume ratio of 1:10.

In some embodiments, in the reaction of the acrylamide molecule inducing silk fibroin film formation, the silk protein concentration is 5%-15%, and the acrylamide concentration is 2.5%-7.5%. In some embodiments, the temperature at which the acrylamide molecule induces silk fibroin film formation ranges from 10°C to 40 ^° C. In some embodiments, the humidity range for the acrylamide molecules to induce silk fibroin film formation is 10%-50%.

Main reagents :

Lithium bromide was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., product number L108934-100g. Acrylamide was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., item number A108465-100g. Potassium hydroxide solution was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., item number P294848-500ml. Silk was purchased from Haozhou Hongbaotang Trading Co., Ltd., item number 18756786088.

Solution preparation :

0.3% (w/v) potassium hydroxide solution: Take 1 mL of 3% (w/v) potassium hydroxide solution and dilute to 10 mL with ultrapure water, and configure to obtain 0.3% (w/v) potassium hydroxide solution .

1% (g/mL) lithium bromide solution: Weigh 0.1 g of lithium bromide solid particles into 10 mL of ultrapure water to prepare a 1% (g/mL) acrylamide solution.

2.5% (g/mL) acrylamide solution: Weigh 0.25 g of acrylamide solid particles into 10 mL of ultrapure water to prepare a 2.5% (g/mL) acrylamide solution.

Unless otherwise specified, the reagents used in the following examples are all conventional reagents in the field, which can be obtained commercially or prepared according to conventional methods in the field, and the specifications are laboratory pure grade. Unless otherwise specified, the experimental methods and conditions used in the following examples are conventional experimental methods and conditions in the art, and reference may be made to relevant experimental manuals, well-known documents or manufacturer's instructions. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Embodiment 1, natural silk prepares silk fibroin contact lens

1. Preparation of silk protein solution

After removing the obvious impurities from the silk, put it into 0.5% (w/v) potassium hydroxide solution and boil it for half an hour to remove the glue, then mix it with lithium bromide solution, stir for 60 minutes, and then put the obtained solution into sterile ultrapure water. Dialysis was performed for 5 days, and sterile ultrapure water was changed every 12 hours to obtain silk protein solution.

2. Preparation of silk fibroin lenses

Take 0.1 mL of 25% (g/mL) acrylamide solution and 1 mL of silk protein solution, add them to a 5 mL centrifuge tube and mix well, take 100 μL of the mixture and drop it into a contact lens mold, and place it at 10 ~40℃, air-dry in a ventilated place to obtain silk fibroin lenses containing acrylamide molecules; soak the lenses in sterile ultrapure water for 60 minutes, then remove the soaking liquid, add sterile ultrapure water for 30 minutes, and repeat the cleaning Three times, and finally the cleaned silk fibroin lenses were placed in sterile physiological saline for preservation.

Example 2. Preparation of anthocyanin-dyed annular colored silk fibroin contact lenses

1. Preparation of silk protein solution

After removing the obvious impurities from the silk, put it into 0.8% (w/v) potassium hydroxide solution and boil it for half an hour to remove the glue, then mix it with the lithium bromide solution, stir for 70 minutes, and then put the obtained solution into sterile ultrapure water. Dialysis was performed for 5 days, and sterile ultrapure water was changed every 12 hours to obtain silk protein solution.

2. Preparation of silk fibroin lenses

Take 0.1 mL of 30% (g/mL) acrylamide solution and 1 mL of silk protein solution, add them to a 5 mL centrifuge tube and mix well, take 100 μL of the mixture and drop it into a contact lens mold, and place it at 10 ~40℃, air-dry in a ventilated place to obtain silk fibroin lenses containing acrylamide molecules; soak the lenses in sterile ultrapure water for 80 minutes, then remove the soaking liquid, add sterile ultrapure water for 30 minutes, and repeat the cleaning Three times, and finally the cleaned silk fibroin lenses were placed in sterile physiological saline for preservation.

Claims (8)

1. a method for preparing silk fibroin contact lenses based on natural silk, is characterized in that: the method is: after the natural silk is degummed by potassium hydroxide solution, the silk protein solution is obtained by dissolving by lithium bromide; after the silk protein solution is dialyzed After mixing with acrylamide, it was dropped into contact lens molds, and air-dried to obtain lenses. 2 . The method for preparing silk fibroin contact lenses based on natural silk according to claim 1 , wherein the lenses are the reaction products of lithium bromide, acrylamide and silk fibroin. 3 . 3. a kind of method for preparing silk fibroin contact lens based on natural silk according to claim 1, it is characterized in that: silk protein solution is dialyzed in sterile ultrapure water for 4～6 days, every 6～24 hours replaces without fibroin. Bacterial ultrapure water. 4. a kind of method for preparing silk fibroin contact lens based on natural silk according to claim 1, is characterized in that: contact lens mould is added acrylamide and silk fibroin mixed solution after cleaning and drying by sterile water; The air drying process temperature is 10~40 ^o C. 5. a kind of method for preparing silk fibroin contact lens based on natural silk according to claim 1, is characterized in that: potassium hydroxide solution is 0.3%～3% (w/v), and the concentration of described lithium bromide solution is 1%~10% (g/mL), the concentration of the acrylamide solution is 2.5%~7.5% (g/mL); the acrylamide solution and the silk protein solution are mixed at a volume ratio of 1:10 . 6. a kind of method for preparing silk fibroin contact lens based on natural silk according to claim 1, is characterized in that: silk protein solution is the solution obtained by mixing with lithium bromide solution after natural silk degumming, preparation method is: by silk After picking up the impurities, put it in an alkaline solution to remove the glue, and then mix and stir with the lithium bromide solution to break the hydrogen bond network in the silk fiber, so as to dissolve the silk fibroin into a silk protein solution and reprocess it, and then remove the silk protein by dialysis. Lithium bromide and soluble impurities contained in the solution. 7. A method for preparing silk fibroin contact lenses based on natural silk according to claim 1, wherein the lens is a silk fibroin film induced by acrylamide molecules, and the preparation method is: combining acrylamide molecules with silk protein The solution was blended to induce the amorphous structure of silk fibroin to form a crystalline stable silk fibroin film, and then the acrylamide was removed by repeated soaking and rinsing. 8. a kind of method for preparing silk fibroin contact lens based on natural silk according to claim 7, is characterized in that: silk protein concentration is 5%～15%, and acrylamide concentration is 2.5%～7.5%; Acrylamide molecule The temperature range for inducing silk fibroin film formation is ^{10-40 o} C; the humidity range for acrylamide molecules for inducing silk fibroin film formation is 10%-50%.

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