Silk fibroin degradable daily-polishing contact lens with moisturizing function and preparation method of silk fibroin degradable daily-polishing contact lens
By preparing biodegradable daily disposable contact lenses made of silk fibroin, the problems of poor moisturizing performance and non-degradability of daily disposable contact lenses have been solved, achieving high moisturizing performance and environmental friendliness.
Patent Information
- Application Number
- CN202511761119.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-27
- Publication Date
- 2026-01-27
AI Technical Summary
Existing daily disposable contact lenses have poor moisturizing properties and are made of non-biodegradable materials, affecting wearing comfort and environmental health.
A combination of silk fibroin, biodegradable polymers, and glycerin was used to prepare biodegradable daily disposable contact lenses with moisturizing function through degumming, dialysis, degassing, and curing.
It significantly improves the moisturizing performance of contact lenses, slows down the dehydration and drying rate of lenses, and ensures that lenses are completely biodegradable, reducing environmental pollution.
Smart Images
Figure SMS_1
Abstract
Description
Technical Field
[0001] This invention relates to the field of contact lens technology, and in particular to a biodegradable daily disposable contact lens with moisturizing function made of silk fibroin and its preparation method. Background Technology
[0002] Contact lenses, especially daily disposable lenses, have become important products for vision correction and cosmetic purposes due to their hygiene and convenience. However, existing daily disposable contact lenses still suffer from poor moisturizing properties. For example, traditional hydrogel or silicone hydrogel contact lenses rely primarily on internal water-locking and the surface properties of polymer materials for moisturizing. After prolonged wear, tear evaporation can easily lead to lens dehydration, causing discomfort such as dry eyes, foreign body sensation, and bloodshot eyes, seriously affecting wearing comfort and eye health. Although there are moisturizing lenses on the market that use internal wetting agents such as polyvinylpyrrolidone or surface coatings, their moisturizing effect is poor, and their application in daily disposable lenses is costly and inconsistent. In addition, existing daily disposable contact lenses have a short lifespan, resulting in a large amount of waste. Furthermore, the materials currently used in daily disposable lenses, such as poly(hydroxyethyl methacrylate), are non-biodegradable plastics. These materials take decades or even centuries to degrade naturally in the environment, posing a potential threat to aquatic ecosystems and human health.
[0003] Therefore, there is an urgent need for a biodegradable daily disposable contact lens that can significantly improve wearing comfort and moisturizing performance. Summary of the Invention
[0004] In view of this, the present invention provides a biodegradable daily disposable contact lens with moisturizing function and a method for preparing the same, in order to solve the problems of poor moisturizing performance and non-biodegradable materials of existing daily disposable contact lenses.
[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a method for preparing biodegradable daily disposable contact lenses with moisturizing function, comprising the following steps: 1) Soak silkworm silk in boiling sodium carbonate aqueous solution to remove glue and obtain silk fibroin fiber. Mix the silk fibroin fiber with solvent and dialyze to obtain silk fibroin protein solution. 2) Mix silk fibroin solution, biodegradable polymer organic solvent and glycerin, and then sequentially degas and solidify to obtain biodegradable daily disposable contact lenses with moisturizing function.
[0006] Preferably, the mass concentration of the sodium carbonate aqueous solution in step 1) is 0.2~0.5%; the mass-volume ratio of the silk fiber to the solvent in step 1) is 1 g: 8~15 mL.
[0007] Preferably, the solvent in step 1) includes an aqueous solution of lithium bromide or an aqueous solution of calcium chloride-ethanol; the mass concentration of lithium bromide in the aqueous solution of lithium bromide is 45-55%; and the molar ratio of calcium chloride, ethanol and water is 1:2:8.
[0008] Preferably, the time for the degumming process in step 1) is 40~120 min; the mixing temperature in step 1) is 60~70℃ and the time is 1~2 h; and the dialysis cutoff in step 1) is 8~14 kDa.
[0009] Preferably, the volume ratio of the silk fibroin solution, the biodegradable polymer organic solvent, and glycerol in step 2) is 1~2:4~5:0.3~0.5.
[0010] Preferably, the mass-volume concentration of the degradable polymer in the organic solvent of the degradable polymer in step 2) is 10-20%.
[0011] Preferably, the degradable polymer in the organic solvent of the degradable polymer in step 2) includes one or more of polylactic acid, polycaprolactone and polyvinyl alcohol; the organic solvent in the organic solvent of the degradable polymer includes one or more of dimethyl sulfoxide, N,N-dimethylformamide and chloroform.
[0012] Preferably, the degassing process in step 2) is vacuum degassing; the vacuum degree of the vacuum degassing is -0.095 to -0.1 MPa, and the time is 30 to 120 min.
[0013] Preferably, the curing temperature in step 2) is 30~40℃ and the time is 24~48 h.
[0014] The present invention also provides a moisturizing silk fibroin biodegradable daily disposable contact lens prepared by the above-mentioned method for preparing moisturizing silk fibroin biodegradable daily disposable contact lenses.
[0015] As can be seen from the above technical solution, compared with the prior art, the beneficial effects of the present invention are as follows: 1. The preparation method of the biodegradable daily disposable contact lens with moisturizing function described in this invention includes the addition of silk fibroin. Silk fibroin is a natural hydrophilic polymer with a large number of hydrophilic groups (such as -OH, -COOH, -NH2) on its molecular chain. This allows the contact lens itself to absorb and lock in much more water than traditional hydrogel materials. Moreover, after the silk fibroin solidifies into a film, it forms a porous three-dimensional network structure. This network structure can physically adsorb and lock in a large number of water molecules like a sponge, greatly improving the moisturizing performance of the contact lens. In addition, glycerol is also added to the preparation method described in this invention. Glycerol has extremely strong hygroscopic properties and can absorb moisture from the air, helping the contact lens maintain moisture. At the same time, the three-dimensional network structure of silk fibroin can also prevent glycerol from leaching or migrating from the lens too quickly, allowing the lens to exert its moisture-absorbing and moisturizing effect for a longer period of time. That is, glycerol and silk fibroin can play a synergistic role, significantly slowing down the rate of lens dehydration and drying.
[0016] 2. The preparation method of the moisturizing silk fibroin biodegradable daily disposable contact lenses of the present invention does not contain any non-degradable raw materials or additives. It is mainly prepared from biodegradable polymers, natural silk fibroin, and glycerin, all of which are biodegradable, ensuring the complete biodegradability of the daily disposable contact lenses of the present invention. Furthermore, the preparation method of the present invention is simple, mild, and environmentally friendly, possessing significant potential for industrial application and economic benefits. Detailed Implementation
[0017] This invention provides a method for preparing biodegradable daily disposable contact lenses with moisturizing function, comprising the following steps: 1) Soak silkworm silk in boiling sodium carbonate aqueous solution to remove glue and obtain silk fibroin fiber. Mix the silk fibroin fiber with solvent and dialyze to obtain silk fibroin protein solution. 2) Mix silk fibroin solution, biodegradable polymer organic solvent and glycerin, and then sequentially degas and solidify to obtain biodegradable daily disposable contact lenses with moisturizing function.
[0018] In this invention, the mass concentration of the sodium carbonate aqueous solution in step 1) is 0.2-0.5%, preferably 0.25-0.45%, more preferably 0.3-0.4%, and even more preferably 0.35%; the mass-volume ratio of the silk fiber to the solvent in step 1) is 1 g: 8-15 mL, preferably 1 g: 9-14 mL, more preferably 1 g: 10-13 mL, and even more preferably 1 g: 11-12 mL.
[0019] In this invention, the solvent in step 1) includes an aqueous solution of lithium bromide or an aqueous solution of calcium chloride-ethanol; the mass concentration of lithium bromide in the aqueous solution of lithium bromide is 45-55%, preferably 46-54%, more preferably 48-52%, and even more preferably 50%; the molar ratio of calcium chloride, ethanol and water is 1:2:8.
[0020] In this invention, the time for the degumming process in step 1) is 40-120 min, preferably 45-100 min, more preferably 50-90 min, and even more preferably 60-80 min; the mixing temperature in step 1) is 60-70°C, preferably 62-68°C, more preferably 63-66°C, and even more preferably 65°C; the mixing time is 1-2 h, preferably 1.2-1.8 h, more preferably 1.3-1.6 h, and even more preferably 1.5 h; the dialysis cutoff in step 1) is 8-14 kDa, preferably 9-13 kDa, more preferably 10-12 kDa, and even more preferably 11 kDa.
[0021] In this invention, the volume ratio of the silk fibroin solution, the biodegradable polymer organic solvent, and glycerol in step 2) is 1~2:4~5:0.3~0.5, preferably 1.2~1.8:4.2~4.8:0.35~0.48, and more preferably 1.3~1.6:4.4~4.7:0.38~0.45.
[0022] In this invention, the mass-volume concentration of the biodegradable polymer in the organic solvent of the biodegradable polymer in step 2) is 10-20%, preferably 12-18%, more preferably 13-16%, and even more preferably 15%.
[0023] In this invention, the degradable polymer in the organic solvent of the degradable polymer in step 2) includes one or more of polylactic acid, polycaprolactone and polyvinyl alcohol; the organic solvent in the organic solvent of the degradable polymer includes one or more of dimethyl sulfoxide, N,N-dimethylformamide and chloroform.
[0024] In this invention, the degassing process in step 2) is vacuum degassing; the vacuum degree of the vacuum degassing is -0.095 to -0.1 MPa, preferably -0.096 to -0.099 MPa, more preferably -0.098 MPa; the vacuum degassing time is 30 to 120 min, preferably 40 to 100 min, more preferably 50 to 80 min, and more preferably 55 to 60 min.
[0025] In this invention, the curing temperature in step 2) is 30~40℃, preferably 32~38℃, more preferably 33~37℃, and even more preferably 35℃; the curing time is 24~48 h, preferably 30~45 h, more preferably 35~42 h, and even more preferably 40 h.
[0026] The present invention also provides a moisturizing silk fibroin biodegradable daily disposable contact lens prepared by the above-mentioned method for preparing moisturizing silk fibroin biodegradable daily disposable contact lenses.
[0027] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0028] Example 1
[0029] 1) After boiling a 0.2% sodium carbonate aqueous solution, the silk is immersed in the boiled sodium carbonate aqueous solution for degumming treatment for 50 min to obtain silk fibroin. Then, the silk fibroin is mixed with a lithium bromide aqueous solution (lithium bromide mass concentration of 45%) at a mass-volume ratio of 1 g: 8 mL at 60℃ for 2 h. Finally, it is placed in a dialysis bag with a retention capacity of 8 kDa for dialysis to obtain a silk fibroin protein solution. 2) Polyvinyl alcohol and dimethyl sulfoxide were mixed to obtain a polyvinyl alcohol solution with a mass-volume concentration of 10%. Then, the silk fibroin solution, polyvinyl alcohol solution and glycerin obtained in step 1) were mixed in a volume ratio of 1:2:0.15. After mixing, the mixture was degassed in a vacuum degassed machine with a vacuum degree of -0.095 MPa for 120 min. Finally, the degassed solution was injected into a contact lens mold and cured at 30°C for 48 h to obtain a biodegradable daily disposable contact lens with moisturizing function.
[0030] Example 2
[0031] 1) After boiling a 0.3% sodium carbonate aqueous solution, the silk is immersed in the boiled sodium carbonate aqueous solution for degumming treatment for 80 min to obtain silk fibroin. Then, the silk fibroin is mixed with a lithium bromide aqueous solution (lithium bromide mass concentration of 45%) at a mass-volume ratio of 1 g: 10 mL at 65℃ for 2 h. Finally, it is placed in a dialysis bag with a 10 kDa cutoff for dialysis to obtain a silk fibroin protein solution. 2) Polyvinyl alcohol and N,N-dimethylformamide were mixed to obtain a polyvinyl alcohol solution with a mass-volume concentration of 12%. Then, the silk fibroin solution, polyvinyl alcohol solution and glycerin obtained in step 1) were mixed in a volume ratio of 2:5:0.5. After mixing, the mixture was degassed in a vacuum degassed machine with a vacuum degree of -0.095 MPa for 100 min. Finally, the degassed solution was injected into a contact lens mold and cured at 35°C for 45 h to obtain a biodegradable daily disposable contact lens with moisturizing function.
[0032] Example 3
[0033] 1) After boiling a 0.5% sodium carbonate aqueous solution, the silk is immersed in the boiled sodium carbonate aqueous solution for degumming treatment for 50 min to obtain silk fibroin. Then, the silk fibroin is mixed with a calcium chloride-ethanol aqueous solution (the molar ratio of calcium chloride, ethanol and water is 1:2:8) at a mass-volume ratio of 1 g:12 mL at 65°C for 1.5 h. Finally, the mixture is placed in a dialysis bag with a 10 kDa cutoff for dialysis to obtain a silk fibroin protein solution. 2) Polylactic acid and dimethyl sulfoxide were mixed to obtain a polyvinyl alcohol solution with a mass-volume concentration of 15%. Then, the silk fibroin solution, polyvinyl alcohol solution and glycerol obtained in step 1) were mixed in a volume ratio of 1:4:0.3. After mixing, the mixture was degassed in a vacuum degaussing machine with a vacuum degree of -0.1 MPa for 50 min. Finally, the degassed solution was injected into a contact lens mold and cured at 40℃ for 35 h to obtain a biodegradable daily disposable silk fibroin contact lens with moisturizing function.
[0034] Example 4
[0035] 1) After boiling a 0.5% sodium carbonate aqueous solution, the silk is immersed in the boiled sodium carbonate aqueous solution for degumming treatment for 100 min to obtain silk fibroin. Then, the silk fibroin is mixed with a lithium bromide aqueous solution (lithium bromide mass concentration of 50%) at a mass-volume ratio of 1 g: 15 mL at 70℃ for 1 h. Finally, it is placed in a dialysis bag with a retention capacity of 14 kDa for dialysis to obtain a silk fibroin protein solution. 2) Mix polyvinyl alcohol with chloroform to obtain a polyvinyl alcohol solution with a mass-volume concentration of 20%. Then, mix the silk fibroin solution, polyvinyl alcohol solution and glycerin obtained in step 1) in a volume ratio of 2:5:0.5. After mixing, degas the solution in a vacuum degassing machine with a vacuum degree of -0.1 MPa for 60 min. Finally, inject the degassed solution into a contact lens mold and cure it at 40℃ for 40 h to obtain a biodegradable daily disposable contact lens with moisturizing function.
[0036] Comparative Example 1
[0037] The only difference between this comparative example and Example 1 is that the silk fibroin solution in step 2) is replaced with silicone hydrogel.
[0038] Comparative Example 2
[0039] The only difference between this comparative example and Example 2 is that the mass-volume ratio of silk fibroin to lithium bromide aqueous solution in step 1) is set to 1 g: 20 mL.
[0040] Comparative Example 3
[0041] The only difference between this comparative example and Example 2 is that the desizing time in step 1) is set to 30 min.
[0042] Comparative Example 4
[0043] The only difference between this comparative example and Example 4 is that glycerol in step 2) is omitted.
[0044] The performance of the daily disposable contact lenses prepared in Examples 1-4 and Comparative Examples 1-4 was tested. Visible light transmittance was measured using a visible light spectrophotometer, measuring the average light transmittance (T%) of the daily disposable contact lenses in the wavelength range of 380-780 nm. Oxygen permeability coefficient DK was measured using a 201T oxygen permeability meter and polarographically according to national standard GB / T 11417.7-2012. The specific method for testing the moisturizing effect was as follows: the daily disposable contact lenses were immersed in deionized water in a beaker, and the beaker was placed in a constant temperature water bath at 37°C. The lenses were weighed at regular intervals until the mass of the fully swollen lenses reached a constant value; this mass was recorded as W. a Then, the daily disposable contact lenses were placed in a petri dish and put into an oven at 37°C. After 10 hours, their mass W was weighed. b To calculate the moisturizing rate of daily disposable contact lenses at 37℃, the formula is: Moisturizing rate = [(W a -W b ) / W a ×100%. The test results are shown in Table 1.
[0045] Table 1 Performance test results of daily disposable contact lenses
[0046] As shown in Table 1, the visible light transmittance, oxygen permeability coefficient, and moisturizing rate of the daily disposable contact lenses prepared in Examples 1-4 of this invention are all higher than those in Comparative Examples 1-4. This indicates that the daily disposable contact lenses of this invention have better performance, solve the problem of poor moisturizing performance of existing daily disposable contact lenses, and improve the wearing comfort of daily disposable contact lenses. Furthermore, the daily disposable contact lenses of this invention are mainly prepared from biodegradable polymers, natural silk fibroin, and glycerin. All of these components are biodegradable, ensuring the complete biodegradability of the daily disposable contact lenses of this invention and giving them broad application prospects.
[0047] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing a biodegradable daily disposable contact lens with moisturizing function, characterized in that, Includes the following steps: 1) Soak silkworm silk in boiling sodium carbonate solution to remove glue and obtain silk fibroin fiber. Mix the silk fibroin fiber with solvent and dialyze to obtain silk fibroin protein solution. 2) Mix silk fibroin solution, biodegradable polymer organic solvent and glycerin, and then sequentially degas and solidify to obtain biodegradable daily disposable contact lenses with moisturizing function.
2. The method for preparing a biodegradable daily disposable contact lens with moisturizing function of silk fibroin according to claim 1, characterized in that, The mass concentration of the sodium carbonate aqueous solution in step 1) is 0.2~0.5%; The mass-to-volume ratio of silk fibroin to solvent in step 1) is 1 g: 8~15 mL.
3. The method for preparing a biodegradable daily disposable contact lens with moisturizing function of silk fibroin according to claim 2, characterized in that, The solvent mentioned in step 1) includes an aqueous solution of lithium bromide or an aqueous solution of calcium chloride-ethanol; The lithium bromide aqueous solution has a lithium bromide mass concentration of 45-55%; the molar ratio of calcium chloride, ethanol and water is 1:2:
8.
4. A method for preparing a biodegradable daily disposable contact lens with moisturizing function based on any one of claims 1 to 3, characterized in that, The time for the adhesive removal process in step 1) is 40~120 min; The mixing temperature in step 1) is 60~70℃, and the time is 1~2 h; The dialysis cutoff in step 1) is 8-14 kDa.
5. The method for preparing a biodegradable daily disposable contact lens with moisturizing function of silk fibroin according to claim 4, characterized in that, In step 2), the volume ratio of the silk fibroin solution, the biodegradable polymer organic solvent, and glycerol is 1~2:4~5:0.3~0.
5.
6. The method for preparing a biodegradable daily disposable contact lens with moisturizing function of silk fibroin according to claim 5, characterized in that, In step 2), the mass-volume concentration of the biodegradable polymer in the organic solvent is 10-20%.
7. The method for preparing a biodegradable daily disposable contact lens with moisturizing function of silk fibroin according to claim 6, characterized in that, The biodegradable polymer in the organic solvent of the biodegradable polymer mentioned in step 2) includes one or more of polylactic acid, polycaprolactone, and polyvinyl alcohol; The organic solvent in the biodegradable polymer organic solvent includes one or more of dimethyl sulfoxide, N,N-dimethylformamide, and chloroform.
8. A method for preparing a biodegradable daily disposable contact lens with moisturizing function based on claim 6 or 7, characterized in that, The degassing process described in step 2) is vacuum degassing; the vacuum degree of the vacuum degassing is -0.095~-0.1 MPa, and the time is 30~120 min.
9. The method for preparing a biodegradable daily disposable contact lens with moisturizing function of silk fibroin according to claim 8, characterized in that, The curing temperature in step 2) is 30~40℃ and the time is 24~48 h.
10. The method for preparing a moisturizing silk fibroin biodegradable daily disposable contact lens according to any one of claims 1 to 9 yields a moisturizing silk fibroin biodegradable daily disposable contact lens.