High-moisture-retention cosmetic contact lens material based on natural raw materials and low-irritation preparation method of high-moisture-retention cosmetic contact lens material

Abstract

The invention relates to the technical field of contact lens materials, in particular to a high-moisturizing cosmetic contact lens material based on natural raw materials and a low-irritation preparation method thereof.The high-moisturizing cosmetic contact lens material is prepared from, by mass, 25%-38% of hyaluronic acid-chitosan compound, 12%-22% of plant extract and 6%-12% of natural moisturizing factors; 0.3%-1.5% of a natural cross-linking agent, and the balance deionized water with the conductivity less than or equal to 1 [mu] S / cm; the mass ratio of hyaluronic acid to chitosan in the hyaluronic acid-chitosan compound is (3: 1)-(5: 1); the plant extract comprises a mixture of aloe polysaccharide and seaweed gel, and the mass ratio of the aloe polysaccharide to the seaweed gel is (2: 1)-(4: 1); the natural moisturizing factor comprises a mixture of glyceryl laurate and betaine in a mass ratio of (1: 1)-(2: 1). Natural synergistic moisturizing is realized through electrostatic net formation of the hyaluronic acid-chitosan compound and combination of aloe polysaccharide and mucoprotein, glutaraldehyde is replaced by genipin, a low-irritation process is realized through dialysis and impurity removal, and the effects of high moisturizing, low irritation, good oxygen permeability and good biocompatibility are realized by combining a double-layer structure and natural moisturizing factors.

Description

Technical Field

[0001] The present invention relates to the technical field of contact lens materials, and in particular to a highly moisturizing cosmetic contact lens material based on natural raw materials and a low-irritation preparation method thereof. Background Art

[0002] In the field of contact lens materials, early hydrogel materials met basic contact lens wear requirements thanks to their hydrophilicity, but their oxygen permeability was limited. With technological advancements, silicone hydrogel materials have become a mainstream choice by significantly improving their oxygen permeability through the introduction of silicon channels. Their oxygen permeability mechanism relies on gas transmission pathways created by silicon oxide groups, opening up new possibilities for long-term contact lens wear.

[0003] However, existing silicone hydrogel materials still have significant defects: First, the oxygen-dependent silicon channel structure will accelerate tear evaporation. The tear evaporation rate has been tested to be ≥1.2μL / min·cm 2 , long-term wear can easily lead to dry eyes and discomfort; secondly, traditional synthetic crosslinkers (such as EGDMA) are difficult to completely remove, and residual amounts can easily trigger eye allergic reactions. Clinical data shows that their sensitization rate is ≥3%. These issues make existing materials difficult to meet the comfort and safety requirements of dry eye patients and those who wear them long-term, and improvement is urgently needed. Summary of the Invention

[0004] The purpose of the present invention is to provide a highly moisturizing cosmetic contact lens material based on natural raw materials and a low-irritation preparation method thereof. In order to solve the above technical problems, the technical solutions provided by the present invention are as follows:

[0005] A highly moisturizing cosmetic contact lens material based on natural raw materials, composed of the following mass percentages: 25% to 38% hyaluronic acid-chitosan complex, 12% to 22% plant extract, 6% to 12% natural moisturizing factor (NMF); 0.3% to 1.5% natural cross-linking agent, and the balance being deionized water with a conductivity of ≤1μS / cm; the hyaluronic acid-chitosan complex has a mass ratio of hyaluronic acid to chitosan of 3:1 to 5:1; the plant extract comprises a mixture of aloe polysaccharide and seaweed gel in a mass ratio of 2:1 to 4:1; and the NMF comprises a mixture of glyceryl laurate and betaine in a mass ratio of 1:1 to 2:1.

[0006] Furthermore, it includes a double-layer structure, the outer layer has a pore size of 5 to 15 μm, a surface contact angle of ≤30°, and contains plant extracts and natural moisturizing factors; the inner layer has a pore size of 2 to 8 μm, an elastic modulus of 0.5 to 1.2 MPa, and contains a hyaluronic acid-chitosan complex.

[0007] Furthermore, the molecular weight of hyaluronic acid is 1.5×10 6Da, the deacetylation degree of the chitosan is ≥90%; the aloe polysaccharide is extracted from aloe vera and has a polysaccharide content of ≥85%, the alginate is derived from brown algae and has a sulfate content of 18% to 22%; the purity of the glycerol laurate is ≥99%, the betaine is derived from natural sugar beets and has a moisture content of ≤0.5%; the natural cross-linking agent is selected from genipin with a purity of ≥98% or tea polyphenols with a catechin content of ≥60%.

[0008] Furthermore, a low-irritation preparation method for a highly moisturizing cosmetic contact lens material based on natural raw materials specifically comprises the following steps:

[0009] Step S1: Composite synthesis: hyaluronic acid with a mass volume concentration of 0.5% to 1.5% was dissolved in deionized water, chitosan acetate solution with a pH of 4.5 to 5.5 was added, and magnetic stirring was carried out at 25° C. and 200 to 400 rpm for 3 hours to form a homogeneous sol;

[0010] Step S2: adding functional components: premixing aloe polysaccharide with a mass volume concentration of 5% to 10% and seaweed gel with a mass volume concentration of 3% to 8% in a 50°C water bath, adding the mixture to the sol of step S1, and treating the mixture with ultrasound at 40 kHz for 30 minutes;

[0011] Step S3: low-temperature cross-linking: adding genipin at a mass volume concentration of 0.05% to 0.2% or tea polyphenols at 0.1% to 0.5%, reacting at 35 to 40° C. for 2 hours under nitrogen protection with an oxygen content of ≤0.5%;

[0012] Step S4: Purification and molding: The gel was injected into a mold with a curvature radius of 7.8-8.2 mm, placed in a dialysis bag with a molecular weight cut-off of 10 kDa, and dialyzed with ultrapure water for 72 hours, with the water changed every 6 hours;

[0013] Step S5: terminal treatment: sterilize with γ-rays at a dose of 10-12 kGy, and seal and package in a buffer solution containing 0.9% NaCl.

[0014] In the present invention, the material uses a hyaluronic acid-chitosan complex with a cross-linking density of 0.3 to 0.8 mmol / g as a matrix, and synergistically forms an interpenetrating network structure with aloe polysaccharide with a molecular weight of 20 to 30 kDa and alginate with a viscosity of 500 mPa·s or more. In addition, a natural moisturizing factor composed of a glycerol derivative with an HLB value of 8 to 12 and betaine with a purity of 98% or more is introduced. The preparation process combines low-temperature ionic cross-linking at a reaction temperature of 40°C with aqueous phase dialysis purification with a molecular weight cutoff of 10 kDa, so that the material has an oxygen permeability coefficient of 85×10 -11 (cm 2 / s)(mL O2 / mL·mmHg), a water content of 68% to 72%, and a cytotoxicity level that reaches level 0 of the ISO 10993-5 standard. It is suitable for patients with dry eyes and those who need to wear it for a long time.

[0015] The advantages of the present invention compared with the prior art are:

[0016] 1. The present invention forms a stable network through electrostatic action of hyaluronic acid-chitosan complex, and aloe polysaccharide specifically binds to corneal surface mucin, which increases the material's ability to bind water molecules by 40% and prolongs the moisturizing time, achieving a moisturizing effect with an initial water content of 70% and a decrease to 67% after 12 hours.

[0017] 2. The present invention uses genipin instead of glutaraldehyde to carry out cross-linking reaction and removes unreacted products through aqueous dialysis, thereby avoiding the production of aldehyde by-products and reducing the risk of sensitization, achieving low-irritation biocompatibility with a cytotoxicity level of 0 and a human corneal epithelial cell survival rate of ≥95%.

[0018] 3. The present invention constructs a composite hydrogel with a double-layer structure. The outer layer contains plant extracts and moisturizing factors, and the inner layer contains a hyaluronic acid-chitosan complex. The natural raw materials form an interpenetrating network, achieving an oxygen permeability coefficient of ≥80×10 -11 , Under the environment of 35℃ and 30% humidity, the moisture content drops by ≤5% within 12 hours. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a flow chart of a low-irritation preparation method for a highly moisturizing cosmetic contact lens material based on natural raw materials in Example 1. DETAILED DESCRIPTION

[0020] The detailed description of the following embodiments is used to exemplify the principles of the present application, but cannot be used to limit the scope of the present application. That is, the present application's highly moisturizing cosmetic contact lens material based on natural raw materials and its low-irritation preparation method are not limited to the described embodiments.

[0021] Example 1

[0022] like Figure 1As shown, a highly moisturizing cosmetic contact lens material based on natural raw materials is composed of the following mass percentages: 25% to 38% hyaluronic acid-chitosan complex, 12% to 22% plant extract, 6% to 12% natural moisturizing factor; 0.3% to 1.5% natural cross-linking agent, and the balance is deionized water with a conductivity of ≤1μS / cm; the mass ratio of hyaluronic acid to chitosan in the hyaluronic acid-chitosan complex is 3:1 to 5:1; the plant extract contains a mixture of aloe polysaccharide and seaweed gel, and the mass ratio of the two is 2:1 to 4:1; the natural moisturizing factor includes a mixture of glycerol laurate and betaine, and the mass ratio of the two is 1:1 to 2:1.

[0023] Furthermore, it includes a double-layer structure, the outer layer has a pore size of 5 to 15 μm, a surface contact angle of ≤30°, and contains plant extracts and natural moisturizing factors; the inner layer has a pore size of 2 to 8 μm, an elastic modulus of 0.5 to 1.2 MPa, and contains a hyaluronic acid-chitosan complex.

[0024] Furthermore, the molecular weight of hyaluronic acid is 1.5×10 6 Da, the deacetylation degree of the chitosan is ≥90%; the aloe polysaccharide is extracted from aloe vera and has a polysaccharide content of ≥85%, the alginate is derived from brown algae and has a sulfate content of 18% to 22%; the purity of the glycerol laurate is ≥99%, the betaine is derived from natural sugar beets and has a moisture content of ≤0.5%; the natural cross-linking agent is selected from genipin with a purity of ≥98% or tea polyphenols with a catechin content of ≥60%.

[0025] Furthermore, a low-irritation preparation method for a highly moisturizing cosmetic contact lens material based on natural raw materials specifically comprises the following steps:

[0026] Step S1: Composite synthesis: hyaluronic acid with a mass volume concentration of 0.5% to 1.5% was dissolved in deionized water, chitosan acetate solution with a pH of 4.5 to 5.5 was added, and magnetic stirring was carried out at 25° C. and 200 to 400 rpm for 3 hours to form a homogeneous sol;

[0027] Step S2: adding functional components: premixing aloe polysaccharide with a mass volume concentration of 5% to 10% and seaweed gel with a mass volume concentration of 3% to 8% in a 50°C water bath, adding the mixture to the sol of step S1, and treating the mixture with ultrasound at 40 kHz for 30 minutes;

[0028] Step S3: low-temperature cross-linking: adding genipin at a mass volume concentration of 0.05% to 0.2% or tea polyphenols at 0.1% to 0.5%, reacting at 35 to 40° C. for 2 hours under nitrogen protection with an oxygen content of ≤0.5%;

[0029] Step S4: Purification and molding: The gel was injected into a mold with a curvature radius of 7.8-8.2 mm, placed in a dialysis bag with a molecular weight cut-off of 10 kDa, and dialyzed with ultrapure water for 72 hours, with the water changed every 6 hours;

[0030] Step S5: terminal treatment: sterilize with γ-rays at a dose of 10-12 kGy, and seal and package in a buffer solution containing 0.9% NaCl.

[0031] In this embodiment, the -COO - With -NH3 + The electrostatic effect forms a stable network, which increases the ability to bind water molecules by 40%. At the same time, the mannose-6-phosphate in aloe polysaccharide is specifically combined with the corneal surface mucin to prolong the moisturizing time and achieve natural synergistic moisturizing. In the preparation process, the gardenia glycoside derivative genipin is used instead of glutaraldehyde for cross-linking reaction to avoid the production of aldehyde by-products, and the unreacted products are removed by aqueous dialysis. The residual cross-linking agent is ≤10ppm as detected by HPLC, forming a low-irritation process.

[0032] Example 2

[0033] Raw materials: Hyaluronic acid-chitosan complex is composed of 1.2% w / v hyaluronic acid and 0.4% w / v chitosan. The molecular weight of hyaluronic acid is 1.2×10 6 Da, the degree of chitosan deacetylation is 92%; the plant extract consists of 8% w / v aloe polysaccharide and alginate, the aloe polysaccharide is extracted from Aloe vera, with a polysaccharide content ≥85% and a molecular weight of 25kDa, the alginate is derived from brown algae, with a sulfate content of 18% to 22%, and a viscosity ≥500mPa·s, and the mass ratio of the two is within the range of 2:1 to 4:1; the natural moisturizing factor consists of glyceryl laurate and betaine, the glyceryl laurate has a purity of ≥99% and an HLB value of 8 to 12, and the betaine is derived from natural sugar beets with a purity of ≥98% and a moisture content of ≤0.5%, and the mass ratio of the two is within the range of 1:1 to 2:1; the natural cross-linking agent is 0.15% w / v genipin, with a purity of ≥98%; the balance is deionized water with a conductivity of ≤1μS / cm.

[0034] The process parameters are:

[0035] 1. Composite synthesis: Dissolve hyaluronic acid in deionized water, add chitosan acetate solution with a pH of 4.5-5.5, and stir magnetically at 200-400 rpm at 25°C for 3 hours to form a homogeneous sol.

[0036] 2. Addition of functional components: premix aloe polysaccharide and seaweed gel in a 50°C water bath, add the above sol, and then treat with 40kHz ultrasound for 30 minutes.

[0037] 3. Low temperature crosslinking: react at 38°C for 2.5 hours under nitrogen protection with oxygen content ≤ 0.5%.

[0038] 4. Purification and molding: The gel was injected into a mold with a curvature radius of 7.8 to 8.2 mm, placed in a dialysis bag with a molecular weight cutoff of 10 kDa, and dialyzed with ultrapure water for 72 hours, changing the water every 6 hours.

[0039] 5. Terminal treatment: sterilize with γ-rays at a dose of 10-12 kGy and seal in a buffer solution containing 0.9% NaCl.

[0040] Its performance data is: oxygen permeability coefficient is 88×10 -11 The initial water content was 70%, which dropped to 67% after 12 hours. The protein adsorption capacity was 3.2 μg / cm after 24 hours of lysozyme solution immersion. 2 .

[0041] It should be noted that the combination of the various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features recorded in this case can be freely combined or combined in any way unless there is a contradiction between them.

[0042] It should also be noted that the embodiments listed above are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and similar changes or modifications made therefrom that can be directly derived from or easily conceived by those skilled in the art based on the disclosure of the present invention are intended to fall within the scope of protection of the present invention.

Claims

1. A highly moisturizing cosmetic contact lens material based on natural raw materials, characterized in that: The invention is composed of the following mass percentages: 25% to 38% hyaluronic acid-chitosan complex, 12% to 22% plant extract, 6% to 12% natural moisturizing factor, 0.3% to 1.5% natural cross-linking agent, and the balance being deionized water with a conductivity of ≤1 μS / cm; the mass ratio of hyaluronic acid to chitosan in the hyaluronic acid-chitosan complex is 3:1 to 5:1; the plant extract comprises a mixture of aloe polysaccharide and seaweed gel in a mass ratio of 2:1 to 4:1; and the natural moisturizing factor comprises a mixture of glyceryl laurate and betaine in a mass ratio of 1:1 to 2:

1.

2. The highly moisturizing cosmetic contact lens material based on natural raw materials according to claim 1, characterized in that: It includes a double-layer structure, the outer layer has a pore size of 5 to 15 μm, a surface contact angle of ≤30°, and contains plant extracts and natural moisturizing factors; the inner layer has a pore size of 2 to 8 μm, an elastic modulus of 0.5 to 1.2 MPa, and contains a hyaluronic acid-chitosan complex.

3. The highly moisturizing cosmetic contact lens material based on natural raw materials according to claim 2, characterized in that: The molecular weight of the hyaluronic acid is 1.5×10 6 Da, the deacetylation degree of the chitosan is ≥90%; the aloe polysaccharide is extracted from aloe vera and has a polysaccharide content of ≥85%, the alginate is derived from brown algae and has a sulfate content of 18% to 22%; the purity of the glycerol laurate is ≥99%, the betaine is derived from natural sugar beets and has a moisture content of ≤0.5%; the natural cross-linking agent is selected from genipin with a purity of ≥98% or tea polyphenols with a catechin content of ≥60%.

4. A low-irritation preparation method for a highly moisturizing cosmetic contact lens material based on natural raw materials, characterized in that: The specific steps include: Step S1: Composite synthesis: hyaluronic acid with a mass volume concentration of 0.5% to 1.5% was dissolved in deionized water, chitosan acetate solution with a pH of 4.5 to 5.5 was added, and magnetic stirring was carried out at 25° C. and 200 to 400 rpm for 3 hours to form a homogeneous sol; Step S2: adding functional components: premixing aloe polysaccharide with a mass volume concentration of 5% to 10% and seaweed gel with a mass volume concentration of 3% to 8% in a 50°C water bath, adding the mixture to the sol of step S1, and treating the mixture with ultrasound at 40 kHz for 30 minutes; Step S3: low-temperature cross-linking: adding genipin at a mass volume concentration of 0.05% to 0.2% or tea polyphenols at 0.1% to 0.5%, reacting at 35 to 40° C. for 2 hours under nitrogen protection with an oxygen content of ≤0.5%; Step S4: Purification and molding: The gel was injected into a mold with a curvature radius of 7.8-8.2 mm, placed in a dialysis bag with a molecular weight cut-off of 10 kDa, and dialyzed with ultrapure water for 72 hours, with the water changed every 6 hours; Step S5: terminal treatment: sterilize with γ-rays at a dose of 10 to 12 kGy and seal and package in a buffer solution containing 0.9% NaCl.

Images