Silk fibroin nail polish for repairing damaged nail surface and preparation method of silk fibroin nail polish

Abstract

The invention discloses silk fibroin nail polish for repairing damaged nail surfaces and a preparation method of the silk fibroin nail polish, and belongs to the technical field of cosmetic materials. The preparation method comprises the following steps: preparing degummed silk; degummed silk is dissolved in an ionic solvent, a silk fibroin dialysis solution is obtained through dialysis, the solution is diluted and then subjected to enzymolysis, and low-molecular-weight silk fibroin is obtained through dialysis, filtration and freeze drying treatment; the preparation method comprises the following steps: dissolving degummed silk in CaCl2-C2H6O-H2O, and carrying out dialysis, filtration and freeze drying treatment, so as to obtain medium molecular weight silk fibroin; uniformly mixing the low-molecular-weight silk fibroin aqueous solution, a penetration enhancer and a humectant to obtain a low-molecular-weight silk fibroin mixed solution; uniformly mixing the medium molecular weight silk fibroin aqueous solution, a film-forming agent and a thickening agent to obtain a medium molecular weight silk fibroin mixed solution; and mixing the two mixed solutions, and adding a preservative to obtain the silk fibroin nail polish. The nail polish disclosed by the invention has the functions of deep repairing, structure strengthening and surface protection.

Description

Technical Field

[0001] This invention relates to the field of cosmetic materials, specifically to a silk fibroin nail polish for repairing damaged nail surfaces and its preparation method. Background Technology

[0002] Nails are primarily composed of highly cross-linked keratin, which has a dense structure, low water content, and lacks self-repair capabilities. When exposed to repeated nail removal, chemical solvent erosion, dry environments, or mechanical friction, they are prone to damage such as roughness, splitting, cracking, and breakage. Common nail repair methods include plant oils, hydrolyzed keratin, silicone-based film-forming agents, and biotin-based repair products, but all have limitations. First, plant oil products such as jojoba oil, argan oil, and olive oil mainly remain on the nail surface; their molecular structure cannot effectively penetrate the dense keratin layer, providing only temporary moisturizing effects and having limited repair effects on damage to the internal structure of the nail plate. Second, although hydrolyzed keratin is similar in composition to nails, its average molecular weight is still relatively large, making it difficult to penetrate the nail's microscopic pores and layered structure. Most of it remains only on the nail surface and cannot reach the deeper layers of the nail plate to exert a repairing effect, resulting in low repair efficiency. Furthermore, silicone-based film-forming agents (such as dimethyl silicone oil and trimethylsiloxane resin) are widely used in nail products to enhance gloss and surface smoothness; however, the film formed by silicone oil is an inert barrier, providing only a temporary illusion of smoothness and strength, and does not possess actual biological repair functions, offering no substantial improvement to existing cracks or delamination. Finally, biotin and vitamins (such as vitamin E and B vitamins) are usually supplemented orally, and their mechanism of action mainly involves regulating metabolism to promote nail growth. This method requires long-term intake to be effective, while the complete nail growth cycle is typically 3-5 months, and cannot directly repair existing nail surface damage, thus failing to meet the need for rapid repair.

[0003] In summary, existing technologies in the field of nail repair still suffer from problems such as insufficient repair penetration, long lead times, and a lack of deep repair capabilities. Therefore, there is a need to develop a novel nail repair material that can effectively penetrate the nail plate structure, promote the repair of damaged areas, and possess both safety and film-forming properties. Summary of the Invention

[0004] To address the technical problems of existing nail polish repair methods, such as poor penetration, superficial application, and poor film-forming properties, this invention provides a silk fibroin nail polish for repairing damaged nail surfaces and its preparation method. The resulting nail polish possesses deep repair, structural strengthening, and surface protection functions, exhibiting a significantly superior overall repair effect compared to existing products, and shows promising application prospects in the field of cosmetic nail care products.

[0005] This invention is achieved through the following technical solution:

[0006] A method for preparing a silk fibroin nail polish for repairing damaged nail surfaces includes the following steps:

[0007] S1. Degummed silk is prepared using degummed silk as raw material;

[0008] S2. Degummed silk is dissolved in an ionic solvent and dialyzed to obtain a silk fibroin dialysis solution. The silk fibroin dialysis solution is diluted and enzymatically hydrolyzed. After dialysis, filtration, and freeze-drying, low molecular weight silk fibroin with a molecular weight of 500-3500 Da is obtained.

[0009] S3. Degummed silk is dissolved in CaCl2-C2H6O-H2O solvent, and after dialysis, filtration and freeze-drying, medium molecular weight silk fibroin with a molecular weight of 10-50kDa is obtained.

[0010] S4. Prepare a low molecular weight silk fibroin aqueous solution, add a penetration enhancer and a moisturizer and mix well to obtain a low molecular weight silk fibroin mixed solution.

[0011] S5. Prepare a medium molecular weight silk fibroin aqueous solution, then add a film-forming agent and a thickener and mix well to obtain a medium molecular weight silk fibroin mixed solution.

[0012] S6. After mixing the low molecular weight silk fibroin mixed solution and the medium molecular weight silk fibroin mixed solution, add the preservative, mix well, adjust the pH value of the system to 5.5-6.5, filter and centrifuge to remove bubbles, and obtain silk fibroin repair nail polish.

[0013] Furthermore, the silkworm cocoons are placed in a sodium carbonate aqueous solution and boiled to remove the sericin. After washing, drying, and cooling, degummed silk is obtained.

[0014] Furthermore, in step S2, the ionic solvent is one of CaCl2 solution, LiBr solution, and ZnCl2 solution, the concentration of the ionic solvent is 9-9.5 mol / L, and the mass ratio of degummed silk to ionic solvent is 1:15-1:20.

[0015] Furthermore, in step S2, the silk fibroin dialysis solution is diluted to a concentration of 2-4 mg / mL and the pH is adjusted to 7.5-8.5 before enzymatic hydrolysis. The mass ratio of enzyme to diluted silk fibroin dialysis solution is 1:100-1:50.

[0016] Furthermore, in step S2, the enzyme used is one or more of trypsin, alkaline protease, pepsin, and chymotrypsin.

[0017] Furthermore, in step S3, the molar ratio of CaCl2, C2H6O, and H2O in the CaCl2-C2H6O-H2O solution is 1:2:8, and the mass ratio of degummed silk to the CaCl2-C2H6O-H2O solution is 1:10-1:15.

[0018] Furthermore, in step S4, the penetration enhancer is one or more of hyaluronic acid, ethanol, and menthol; the moisturizer is one or more of propylene glycol, glycerin, and panthenol; the concentration of low molecular weight silk fibroin in the low molecular weight silk fibroin mixed solution is 1-10%, the concentration of the penetration enhancer is 0.05-0.2%, and the concentration of the moisturizer is 3-13%.

[0019] Furthermore, in step S5, the film-forming agent is one or more of polyvinyl alcohol, polyvinylpyrrolidone, and acrylic resin; the thickener is one of xanthan gum, hydroxyethyl cellulose, and carbomer; the concentration of medium molecular weight silk fibroin in the medium molecular weight silk fibroin mixed solution is 0.5-5%, the concentration of film-forming agent is 30-50%, and the concentration of thickener is 0.4-2%.

[0020] Furthermore, in step S6, the low molecular weight silk fibroin mixed solution and the medium molecular weight silk fibroin mixed solution are mixed at a mass ratio of 1-1.5:2, and the preservative is one of benzyl alcohol, paraben, and potassium sorbate, accounting for 0.1-0.8 wt% of the mass of the mixed system solution.

[0021] A silk fibroin nail polish prepared according to the above method for repairing damaged nail surfaces.

[0022] The beneficial effects of this invention are:

[0023] The technical solution of the present invention has the following advantages compared with the prior art:

[0024] This invention utilizes enzymatic hydrolysis to form low-molecular-weight silk fibroin, followed by hydrolysis of the degummed fibers using a CaCl2 / ethanol / aqueous solution system to form medium-molecular-weight silk fibroin, thereby preparing a silk fibroin repair nail polish. The low-molecular-weight silk fibroin can penetrate the microstructure of the nail keratin layer, specifically repairing damaged areas of the nail plate. The medium-molecular-weight silk fibroin, through synergistic action with the film-forming system, forms a protective film on the surface, enhancing the mechanical strength and structural stability of the nail surface, significantly improving nail breakage resistance, and increasing nail surface strength and abrasion resistance (the nail polish can be used daily, and significant improvement in nail structure can be seen after 7-14 days). Furthermore, it can improve nail surface smoothness and gloss, showing promising application prospects in the field of cosmetic nail care. Attached Figure Description

[0025] Figure 1 This is a photograph of the silk fibroin repair nail polish prepared according to the present invention.

[0026] Figure 2 This is a comparison chart showing the durability test results of the nail polishes prepared in Example 1 and Comparative Examples 2 and 3. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The present invention provides a method for preparing a silk fibroin repair nail polish for repairing damaged nail surfaces, comprising the following steps:

[0029] Step (1): Place the silkworm cocoons in a 0.04-0.05 mol / L sodium carbonate aqueous solution and boil at 100℃ for 1-2 hours to remove sericin (the ratio of silkworm cocoons to sodium carbonate aqueous solution is 1g: 150-300ml). After removing them, wash them with deionized water, put them in an oven to dry, and cool them to room temperature to obtain degummed silk.

[0030] Step (2): The degummed silk prepared in step (1) is heated and stirred in a water bath at 55-65℃ for 4-5 hours with an ionic solvent (one of CaCl2 solution, LiBr solution, or ZnCl2 solution, with a concentration of 9-9.5 mol / L and a mass ratio of degummed silk to ionic solvent of 1:15-1:20). After cooling, the resulting silk fibroin solution A is placed in a MWC3500 dialysis bag and dialyzed in deionized water at 4℃ for 2-3 days. Impurities were filtered through a 00-mesh filter to obtain silk fibroin dialysis solution A. Silk fibroin dialysis solution A was diluted to a concentration of 2-4 mg / mL, and the pH was adjusted to 7.5-8.5 with 0.1 mol / L NaOH solution. An enzyme (one or more of trypsin, alkaline protease, pepsin, and chymotrypsin, with a mass ratio of enzyme to diluted silk fibroin dialysis solution A of 1:100-1:50) was added, and hydrolysis was performed at room temperature for 4-12 hours. After the reaction, the enzyme was inactivated by heating in a 90°C water bath. Dialysis was performed for 2-3 days at room temperature using a MWC 3500 Da dialysis bag to remove undegraded macromolecular residues. Impurities were then filtered through a 200-mesh filter to obtain a medium molecular weight silk fibroin solution. The solution was then freeze-dried at -20 to -50°C to obtain low molecular weight silk fibroin (molecular weight 500-3500 Da).

[0031] Step (3): The degummed silk prepared in step (1) and CaCl2-C2H6O-H2O solution (the molar ratio of CaCl2, C2H6O, and H2O is 1:2:8; the mass ratio of degummed silk to CaCl2-C2H6O-H2O solution is 1:10-1:15) are heated in a water bath at 65-75℃ and stirred for 2-4 hours. After cooling, the resulting silk fibroin solution B is placed in an MWC12000 dialysis bag and dialyzed in deionized water at 4℃ for 2-3 days. Impurities are filtered through a 200-mesh filter to obtain silk fibroin dialysis solution B. The solution is then freeze-dried at -20 to -50℃ to obtain medium molecular weight silk fibroin (molecular weight of 10-50 kDa).

[0032] Step (4): Add the low molecular weight silk fibroin obtained in step (2) to deionized water, heat and stir in a water bath to dissolve, prepare a low molecular weight silk fibroin solution, and then add a penetration enhancer (one or more of hyaluronic acid, ethanol, and menthol) and a moisturizer (one or more of propylene glycol, glycerin, and panthenol, preferably), stir thoroughly to obtain a low molecular weight silk fibroin mixed solution. The concentration of low molecular weight silk fibroin in the low molecular weight silk fibroin mixed solution is 1-10%, the concentration of penetration enhancer is 0.05-0.2%, and the concentration of moisturizer is 3-13%.

[0033] Step (5): Add the medium molecular weight silk fibroin obtained in step (3) to deionized water, stir and dissolve at room temperature to prepare a medium molecular weight silk fibroin solution. Then add a film-forming agent (one or more of polyvinyl alcohol, polyvinylpyrrolidone, and acrylic resin) and a thickener (one of xanthan gum, hydroxyethyl cellulose, and carbomer) and stir thoroughly to obtain a medium molecular weight silk fibroin mixed solution. The concentration of medium molecular weight silk fibroin in the medium molecular weight silk fibroin mixed solution is 0.5-5%, the concentration of film-forming agent is 30-50%, and the concentration of thickener is 0.4-2%.

[0034] Step (6): Mix the low molecular weight silk fibroin mixed solution prepared in step (4) and the medium molecular weight silk fibroin mixed solution prepared in step (5) at a mass ratio of 1-1.5:2. Add a preservative, and add or omit at least one of glycerophosphate choline and isomaltitol. After thorough stirring, adjust the pH of the mixed system solution to 5.5-6.5 with 0.01-0.05 m / L sodium hydroxide solution. The preservative is one of benzyl alcohol, p-hydroxybenzoate, and potassium sorbate, and the preservative accounts for 0.1-0.8 wt% of the mass of the mixed system solution.

[0035] Step (7): Filter the mixed system solution through an 800-1000 mesh filter to remove insoluble matter, centrifuge to remove bubbles, and obtain silk fibroin repair nail polish for repairing damaged nail surfaces.

[0036] The preferred embodiment is as follows:

[0037] Example 1

[0038] (1) Weigh 20g of silkworm cocoons and place them in 4L of sodium carbonate aqueous solution with a concentration of 0.04mol / L. Boil at 100℃ for 1.5h to remove sericin. After taking them out, wash them 5 times with deionized water and put them in an oven at 60℃ for 24h. Then cool them to room temperature to obtain degummed silk.

[0039] (2) 10g of degummed silk and 150mL of LiBr solution (concentration of 9.3mol / L) were heated in a water bath at 60℃ and stirred for 4h. After cooling, silk fibroin solution A was obtained. The silk fibroin solution was placed in a MWC3500 dialysis bag and dialyzed in deionized water at 4℃ for 3 days. Impurities were filtered through a 200-mesh filter to obtain silk fibroin dialysis solution A. Silk fibroin dialysis solution A was diluted with deionized water to 4mg / mL, and the pH was adjusted to 7.5 with 0.1mol / L sodium hydroxide solution. 0.2g of trypsin was added (the mass ratio of trypsin to silk fibroin in the dialysis solution was 1:100). The solution was hydrolyzed at room temperature for 12h. After the reaction was completed, the enzyme was inactivated by heating in a water bath at 90℃ for 10min. The solution was then used in a MWC3500 dialysis bag. Dialysis with a 3500 Da dialysis bag at room temperature for 3 days to remove undegraded macromolecular residues. Impurities were filtered through a 200-mesh filter to obtain a medium molecular weight silk fibroin solution. The solution was then freeze-dried in a freeze dryer at -20 to -50°C for 72 hours to obtain low molecular weight silk fibroin (molecular weight 500-3500 Da).

[0040] Besides enzymatic hydrolysis, low molecular weight silk fibroin can also be prepared by ultrasonic lysis.

[0041] (3) 10g of degummed silk and 150mL of CaCl2-C2H6O-H2O solution (the molar ratio of CaCl2, C2H6O and H2O is 1:2:8) were heated in a water bath at 70℃ and stirred for 4h. After cooling, silk fibroin solution B was obtained. Silk fibroin solution B was placed in a MWC12000 dialysis bag and dialyzed in deionized water at 4℃ for 3 days. Impurities were filtered with a 200-mesh filter to obtain silk fibroin dialysis solution B. It was freeze-dried at -20 to -50℃ for 72h to obtain medium molecular weight silk fibroin (molecular weight is 10-50kDa).

[0042] (4) Add 0.15g of the low molecular weight silk fibroin obtained in step (2) to 5mL of deionized water, heat and stir in a water bath at 30℃ to dissolve, and prepare a low molecular weight silk fibroin solution. Then add 0.01g of hyaluronic acid with a molecular weight of 5000, 0.17g of panthenol and 0.5g of propylene glycol and stir thoroughly to obtain a low molecular weight silk fibroin mixed solution.

[0043] (5) Add 0.1g of medium molecular weight silk fibroin obtained in step (3) to 5g of deionized water, stir and dissolve at room temperature to prepare a medium molecular weight silk fibroin solution, then add 5g of acrylic resin and 0.05g of hydroxyethyl cellulose and stir thoroughly to obtain a medium molecular weight silk fibroin mixed solution.

[0044] (6) Stir 5g of low molecular weight silk fibroin mixed solution and 10g of medium molecular weight silk fibroin mixed solution evenly, add 0.04g of potassium sorbate, stir thoroughly, and then adjust the pH of the mixed system to 6.5 with 0.01m / L sodium hydroxide solution.

[0045] (7) The mixed system solution was filtered with a 900-mesh filter to remove insoluble matter, and centrifuged at 4500 rpm / min for 30 min to remove bubbles, so as to obtain silk fibroin repair nail polish for repairing damaged nail surfaces.

[0046] Comparative Example 1

[0047] Nail polish was prepared according to Example 1, except that the 0.01g of hyaluronic acid with a molecular weight of 5000 added in step (4) was replaced with 0.01g of hyaluronic acid with a molecular weight of 100,000.

[0048] Comparative Example 2

[0049] Nail polish was prepared according to Example 1, except that 0.05g of hydroxyethyl cellulose was not added in step (5).

[0050] Comparative Example 3

[0051] Nail polish was prepared according to Example 1, except that 5g of low molecular weight silk fibroin mixed solution was not added in step (6).

[0052] Comparative Example 4

[0053] Nail polish was prepared according to Example 1, except that the mixed system solution in step (7) was not filtered through a 900-mesh filter and was directly centrifuged to remove bubbles.

[0054] The drying times of the nail polishes prepared in Example 1 and Comparative Example 1 were compared. The test method was as follows: Under the conditions of room temperature (20±5)℃ and relative humidity <80%, the glass slides were cleaned with ethyl acetate and allowed to dry. After drying, a brush was dipped in nail polish and applied to the glass slide in one go. A stopwatch was immediately started, and after 7 minutes, the slides were touched to check for dryness. The test results are shown in Table 1. The comparison of drying times shows that low molecular weight hyaluronic acid has a faster drying time than high molecular weight hyaluronic acid.

[0055] Table 1

[0056] Example 1 Comparative Example 1 Drying time (min) 5 7

[0057] The durability of the silk fibroin repair nail polishes prepared in Example 1, Comparative Examples 2 and 3 was compared. The test method was as follows: At room temperature (20 ± 5) °C, a glass slide was cleaned with ethyl acetate and allowed to dry. After drying, a brush was used to apply a layer of nail polish to the slide. After 24 hours, five horizontal and five vertical intersecting lines were drawn with a needle, each line spaced 2.5 mm apart. The degree of nail polish peeling was observed. The test results are as follows: Figure 2 As shown: In Comparative Example 2, the nail polish edges peeled off after being drawn; in Comparative Example 3, the nail polish film was thin after forming, and the edges of the drawn lines were easily peeled off; in Example 1, the nail polish repaired with silk fibroin had clear edges with no peeling. The comparison of nail polish adhesion shows that hydroxyethyl cellulose significantly improves the adhesion of the nail polish film after it forms; the addition of low molecular weight silk fibroin makes the nail polish film thickness and adhesion even better after it forms.

[0058] The uniformity and pinhole issues of the silk fibroin repair nail polishes prepared in Example 1 and Comparative Example 4 were compared. The test method was as follows: at room temperature (20±5)℃, the glass slides were cleaned with ethyl acetate and allowed to dry. After drying, a brush was dipped in nail polish and a layer was applied to the glass slide. The uniformity of the nail polish, presence of particles, and pinholes were observed. The test results are as follows: the nail polish of Example 1, when applied to the glass slide and observed under light, showed no particle texture and was evenly applied without pinholes; the nail polish of Comparative Example 4, when applied to the glass slide and observed under light, showed obvious particle texture and minor pinholes. From the comparison of nail polish uniformity, it can be seen that the silk fibroin repair nail polish using a 900-mesh sieve was more evenly distributed, smoother to apply, and free of pinholes.

[0059] Example 2

[0060] Nail polish was prepared according to Example 1, except that in step (6), 0.1g of glycerophosphate choline and 0.18g of isomaltitol were added and mixed together.

[0061] Example 3

[0062] Nail polish was prepared according to Example 2, except that 0.1g of glycerophosphate choline was not added in step (6).

[0063] Example 4

[0064] Nail polish was prepared according to Example 2, except that 0.18g of isomaltitol was not added in step (6).

[0065] Tests showed that the drying time of the nail polishes in Examples 2-4 was all within 5 minutes. The adhesion test showed that the edges of the lines were clear and did not peel off. The uniformity and pinhole problems tests also showed that there was no grainy texture when observed under light, and the application was even without pinholes.

[0066] Eighty individuals with brittle, broken, or ridged nails were randomly selected as trial subjects and divided into four groups of 20 each. This ensured that the degree and number of nail damage issues were consistent across groups, minimizing experimental error. The nail strength was first tested using a Vickers hardness tester. Then, each group was coated with nail polish prepared in Examples 1-4, applied once daily at 9:00 AM for 14 consecutive days. Nail strength was tested after 14 days, and the number of individuals in each group whose nail ridges became shallower was recorded. The results are shown in Table 1.

[0067] Table 1

[0068]

[0069] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a silk fibroin nail polish for repairing damaged nail surfaces, characterized in that, Includes the following steps: S1. Degummed silk is prepared using degummed silk as raw material; S2. Degummed silk is dissolved in an ionic solvent and dialyzed to obtain a silk fibroin dialysis solution. The silk fibroin dialysis solution is diluted and enzymatically hydrolyzed. After dialysis, filtration, and freeze-drying, low molecular weight silk fibroin with a molecular weight of 500-3500 Da is obtained. S3. Degummed silk is dissolved in CaCl2-C2H6O-H2O solvent, and after dialysis, filtration and freeze-drying, medium molecular weight silk fibroin with a molecular weight of 10-50kDa is obtained. S4. Prepare a 2.5-3 wt% low molecular weight silk fibroin aqueous solution, add a penetration enhancer and a moisturizer and mix well to obtain a low molecular weight silk fibroin mixed solution. S5. Prepare a medium molecular weight silk fibroin aqueous solution with a concentration of 1-2 wt%, then add a film-forming agent and a thickener and mix evenly to obtain a medium molecular weight silk fibroin mixed solution. S6. After mixing the low molecular weight silk fibroin mixed solution and the medium molecular weight silk fibroin mixed solution, add the preservative, mix well, adjust the pH value of the system to 5.5-6.5, filter and centrifuge to remove bubbles, and obtain silk fibroin repair nail polish.

2. The method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, Silkworm cocoons are placed in a sodium carbonate aqueous solution and boiled to remove sericin. After washing, drying and cooling, degummed silk is obtained.

3. The method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, In step S2, the ionic solvent is one of CaCl2 solution, LiBr solution, or ZnCl2 solution, the concentration of the ionic solvent is 9-9.5 mol / L, and the mass ratio of degummed silk to ionic solvent is 1:15-1:

20.

4. The method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, In step S2, the silk fibroin dialysis solution is diluted to a concentration of 2-4 mg / mL and the pH is adjusted to 7.5-8.5 before enzymatic hydrolysis. The mass ratio of enzyme to diluted silk fibroin dialysis solution is 1:100-1:

50.

5. A method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, In step S2, the enzyme used is one or more of trypsin, alkaline protease, pepsin, and chymotrypsin.

6. A method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, In step S3, the molar ratio of CaCl2, C2H6O, and H2O in the CaCl2-C2H6O-H2O solution is 1:2:8, and the mass ratio of degummed silk to the CaCl2-C2H6O-H2O solution is 1:10-1:

15.

7. A method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, In step S4, the penetration enhancer is one or more of hyaluronic acid, ethanol, and menthol; the moisturizer is one or more of propylene glycol, glycerin, and panthenol; the concentration of low molecular weight silk fibroin in the low molecular weight silk fibroin mixed solution is 1-10%, the concentration of penetration enhancer is 0.05-0.2%, and the concentration of moisturizer is 3-13%.

8. A method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, In step S5, the film-forming agent is one or more of polyvinyl alcohol, polyvinylpyrrolidone, and acrylic resin; the thickener is one of xanthan gum, hydroxyethyl cellulose, and carbomer; the medium molecular weight silk fibroin mixed solution has a medium molecular weight silk fibroin concentration of 0.5-5%, a film-forming agent concentration of 30-50%, and a thickener concentration of 0.4-2%.

9. A method for preparing a silk fibroin nail polish for repairing damaged nail surfaces according to claim 1, characterized in that, In step S6, the low molecular weight silk fibroin mixed solution and the medium molecular weight silk fibroin mixed solution are mixed at a mass ratio of 1-1.5:

2. The preservative is one of benzyl alcohol, paraben, and potassium sorbate, and the preservative accounts for 0.1-0.8 wt% of the mass of the mixed system solution.

10. A silk fibroin nail polish for repairing damaged nail surfaces, prepared by the method according to any one of claims 1-9.

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