Gradient composite coating for contact lenses and preparation method of gradient composite coating

Abstract

The invention provides a gradient composite coating for contact lenses and a preparation method of the gradient composite coating, and belongs to the technical field of new coating materials. The method comprises the following steps: firstly, performing oxygen plasma activation on a contact lens substrate to obtain an activated substrate; the activated substrate is placed in a first coating solution for a first reaction, and a substrate with a first coating is obtained; and finally, placing the substrate with the first coating in a second coating solution for second reaction to obtain a substrate with a gradient composite coating, wherein the first coating solution comprises gamma-polyglutamic acid, and the second coating solution comprises hyaluronic acid. According to the coating with the gradient structure, the gamma-polyglutamic acid inner layer has lubricity and antibacterial property, the moisturizing effect of the contact lens can be improved by combining the hyaluronic acid surface layer and the gamma-polyglutamic acid inner layer, the moisturizing time is longer, and the protein adsorption amount is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of new coating materials, and in particular to a gradient composite coating for contact lenses and a preparation method thereof. Background Art

[0002] Silicone hydrogel contact lenses made from silicone hydrogel are popular for their high oxygen permeability. However, due to the extremely high mobility and surface activity of the siloxane functional groups in silicone hydrogel, they easily migrate to the lens surface, making it hydrophobic. This hydrophobic surface not only greatly reduces the comfort of the contact lens but also easily attracts protein deposits. These shed proteins may denature, leading to bacterial adsorption, inflammation, and even eye diseases such as keratitis and conjunctivitis. Good surface wettability improves lens comfort and prevents protein deposition on the lens surface. Therefore, it is of great significance to develop a gradient composite coating for contact lenses and its preparation method to improve the hydrophobicity of contact lenses. Summary of the Invention

[0003] The object of the present invention is to provide a gradient composite coating for contact lenses and a preparation method thereof, so as to solve the problem of poor wettability of contact lenses in the prior art.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing a gradient composite coating for contact lenses, comprising the following steps:

[0006] (1) performing oxygen plasma activation on a contact lens substrate to obtain an activated substrate;

[0007] (2) placing the activated substrate in a first coating solution to perform a first reaction to obtain a substrate with a first coating;

[0008] The first coating solution is made of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride, N-hydroxysuccinimide and γ-polyglutamic acid;

[0009] (3) placing the substrate with the first coating in a second coating solution to perform a second reaction, thereby obtaining a substrate with a gradient composite coating;

[0010] The second coating solution is made of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride, N-hydroxysuccinimide and hyaluronic acid.

[0011] Preferably, in step (1), the process parameters of the oxygen plasma treatment are: oxygen flow rate of 40 to 80 mL / min, power of 100 to 200 W, and time of 60 to 120 s.

[0012] Preferably, the concentration of γ-polyglutamic acid in the first coating solution is 2-5 wt %.

[0013] Preferably, the temperature of the first reaction is 20-30° C., and the time is 10-30 min.

[0014] Preferably, the concentration of hyaluronic acid in the second coating solution is 0.1-0.5 wt %.

[0015] Preferably, in the first coating solution and the second coating solution, the mass ratio of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride to N-hydroxysuccinimide is independently 1 to 5:1.

[0016] Preferably, the temperature of the second reaction is 20-30° C., and the time is 3-6 hours.

[0017] Preferably, dialysis is performed after the second reaction is completed.

[0018] The present invention also provides a gradient composite coating prepared by the above-mentioned method for preparing the gradient composite coating for contact lenses.

[0019] Beneficial effects of the present invention:

[0020] The present invention first performs oxygen plasma activation on the contact lens substrate, introduces active groups on the surface of the contact lens substrate, and provides anchoring points for the subsequent formation of a coating.

[0021] The gradient structure composite coating prepared by the present invention, wherein the first coating formed by γ-polyglutamic acid has both lubricity and antibacterial properties, and the combination of the hyaluronic acid surface layer and the γ-polyglutamic acid inner layer can improve the moisturizing effect of the contact lens, extend the moisturizing time, and reduce the amount of protein adsorption.

[0022] The composite coating with a gradient structure prepared by the present invention can also reduce the friction coefficient of contact lenses. DETAILED DESCRIPTION

[0023] The present invention provides a method for preparing a gradient composite coating for contact lenses, comprising the following steps:

[0024] (1) performing oxygen plasma activation on a contact lens substrate to obtain an activated substrate;

[0025] (2) placing the activated substrate in a first coating solution to perform a first reaction to obtain a substrate with a first coating;

[0026] The first coating solution is made of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride, N-hydroxysuccinimide and γ-polyglutamic acid;

[0027] (3) placing the substrate with the first coating in a second coating solution to perform a second reaction, thereby obtaining a substrate with a gradient composite coating;

[0028] The second coating solution is made of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride, N-hydroxysuccinimide and hyaluronic acid.

[0029] In the present invention, in step (1), the process parameters of the oxygen plasma treatment are: an oxygen flow rate of 40 to 80 mL / min, preferably 50 to 70 mL / min, and more preferably 60 mL / min; a power of 100 to 200 W, preferably 100 W, 120 W, 150 W, 180 W, and 200 W; and a treatment time of 60 to 120 s, preferably 80 s, 90 s, 100 s, and 110 s.

[0030] In the present invention, the concentration of γ-polyglutamic acid in the first coating solution is 2 to 5 wt %, preferably 2.5 to 4.5 wt %, and more preferably 3 to 4 wt %.

[0031] In the present invention, the molecular weight of the γ-polyglutamic acid is preferably 80,000 to 120,000 Da.

[0032] In the present invention, the temperature of the first reaction is 20-30° C., preferably 25° C., and the time is 10-30 min, preferably 15-25 min, and more preferably 20 min.

[0033] In the present invention, the concentration of hyaluronic acid in the second coating solution is 0.1-0.5 wt %, preferably 0.2-0.4 wt %, and more preferably 0.3 wt %.

[0034] In the present invention, the molecular weight of the hyaluronic acid is preferably 1000 to 2000 kDa.

[0035] In the present invention, in the first coating solution and the second coating solution, the mass ratio of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride to N-hydroxysuccinimide is independently 1 to 5:1, preferably 2:1, 2.5:1, 3:1, 3.5:1, or 4:1.

[0036] In the present invention, the temperature of the second reaction is 20-30° C., preferably 25° C., and the time is 3-6 h, preferably 4-5 h.

[0037] In the present invention, dialysis is performed after the second reaction is completed.

[0038] In the present invention, the dialysis is performed with deionized water for 3 to 6 days.

[0039] The present invention also provides a gradient composite coating prepared by the above-mentioned method for preparing the gradient composite coating for contact lenses.

[0040] The technical solutions provided by the present invention are 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.

[0041] Example 1

[0042] Place the contact lens in a plasma device, set the oxygen flow rate to 60 mL / min, the power to 150 W, and treat for 80 seconds to obtain an activated matrix for later use.

[0043] A 3 wt% γ-polyglutamic acid solution was prepared, wherein the molecular weight of γ-polyglutamic acid was 10 kDa. The activated substrate was placed in the γ-polyglutamic acid solution, and then 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 3:1. The pH value was adjusted to 5.0, and the reaction was carried out at 25° C. for 20 minutes to obtain a substrate with a first coating.

[0044] A hyaluronic acid solution with a concentration of 0.3wt% and a molecular weight of 15000kDa was prepared, and the substrate with the first coating was placed therein. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimine hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 3:1, and the pH value was adjusted to 5.0. The reaction was carried out at 25°C for 4h. After the reaction was completed, the substrate was dialyzed with deionized water for 5 days to obtain a contact lens with a gradient composite coating.

[0045] Example 2

[0046] Place the contact lens in a plasma device, set the oxygen flow rate to 80 mL / min, the power to 100 W, and treat for 120 s to obtain an activated matrix for later use.

[0047] A 5wt% γ-polyglutamic acid solution was prepared, and the activated substrate was placed in the γ-polyglutamic acid solution, wherein the molecular weight of γ-polyglutamic acid was 10kDa. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 4:1, and the pH value was adjusted to 5.0. The reaction was carried out at 20°C for 25 minutes to obtain a substrate with a first coating.

[0048] A hyaluronic acid solution with a concentration of 0.4wt% and a molecular weight of 15000kDa was prepared, and the substrate with the first coating was placed therein. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 4:1, and the pH value was adjusted to 5.0. The reaction was carried out at 25°C for 4.5h. After the reaction was completed, the substrate was dialyzed with deionized water for 6 days to obtain a contact lens with a gradient composite coating.

[0049] Example 3

[0050] Place the contact lens in a plasma device, set the oxygen flow rate to 40 mL / min, the power to 200 W, and treat for 60 seconds to obtain an activated matrix for later use.

[0051] A 2 wt% γ-polyglutamic acid solution was prepared, and the activated substrate was placed in the γ-polyglutamic acid solution, wherein the molecular weight of γ-polyglutamic acid was 10 kDa. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 5:1, the pH value was adjusted to 5.0, and the reaction was carried out at 30° C. for 15 minutes to obtain a substrate with a first coating.

[0052] A hyaluronic acid solution with a concentration of 0.2wt% and a molecular weight of 15000kDa was prepared, and the substrate with the first coating was placed therein. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimine hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 5:1, and the pH value was adjusted to 5.0. The reaction was carried out at 25°C for 5.5h. After the reaction was completed, the substrate was dialyzed with deionized water for 4 days to obtain a contact lens with a gradient composite coating.

[0053] Example 4

[0054] Place the contact lens in a plasma device, set the oxygen flow rate to 50 mL / min, the power to 120 W, and treat for 100 s to obtain an activated matrix for later use.

[0055] A 4 wt% γ-polyglutamic acid solution was prepared, and the activated substrate was placed in the γ-polyglutamic acid solution, wherein the molecular weight of γ-polyglutamic acid was 10 kDa. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 2:1, and the pH value was adjusted to 5.0. The reaction was carried out at 25° C. for 20 minutes to obtain a substrate with a first coating.

[0056] A hyaluronic acid solution with a concentration of 0.1wt% and a molecular weight of 15000kDa was prepared, and the substrate with the first coating was placed therein. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 2:1, and the pH value was adjusted to 5.0. The reaction was carried out at 25°C for 4h. After the reaction, the substrate was dialyzed with deionized water for 5 days to obtain a contact lens with a gradient composite coating.

[0057] Example 5

[0058] Place the contact lens in a plasma device, set the oxygen flow rate to 70 mL / min, the power to 180 W, and treat for 70 seconds to obtain an activated matrix for later use.

[0059] A 4.5 wt% γ-polyglutamic acid solution was prepared, and the activated substrate was placed in the γ-polyglutamic acid solution, wherein the molecular weight of γ-polyglutamic acid was 10 kDa. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 3.5:1, and the pH value was adjusted to 5.0. The reaction was carried out at 20° C. for 30 minutes to obtain a substrate with a first coating.

[0060] A hyaluronic acid solution with a concentration of 0.5wt% and a molecular weight of 15000kDa was prepared, and the substrate with the first coating was placed therein. Then, 1-(3-dimethylaminopropyl)-3-ethyldiimine hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 3.5:1, and the pH value was adjusted to 5.0. The reaction was carried out at 25°C for 5h. After the reaction was completed, the substrate was dialyzed with deionized water for 6 days to obtain a contact lens with a gradient composite coating.

[0061] Comparative Example 1

[0062] Place the contact lens in a plasma device, set the oxygen flow rate to 60 mL / min, the power to 150 W, and treat for 80 seconds to obtain an activated matrix for later use.

[0063] A hyaluronic acid solution with a concentration of 0.3wt% and a molecular weight of hyaluronic acid of 15000kDa was prepared, an activated matrix was placed therein, and then 1-(3-dimethylaminopropyl)-3-ethyldiimine hydrochloride and N-hydroxysuccinimide were added in a mass ratio of 3:1. The pH value was adjusted to 5, and the reaction was carried out at 25°C for 4h. After the reaction, the solution was dialyzed with deionized water for 5 days to obtain a contact lens with a hyaluronic acid coating.

[0064] Comparative Example 2

[0065] Place the contact lens in a plasma device, set the oxygen flow rate to 60 mL / min, the power to 150 W, and treat for 80 seconds to obtain an activated matrix for later use.

[0066] A 3 wt% γ-polyglutamic acid solution was prepared, and an activated matrix was placed in the γ-polyglutamic acid solution, wherein the molecular weight of the γ-polyglutamic acid was 10 kDa. 1-(3-dimethylaminopropyl)-3-ethyldiimine hydrochloride and N-hydroxysuccinimide were then added in a mass ratio of 3:1. The pH value was adjusted to 5.0, and the mixture was reacted at 25° C. for 20 minutes to obtain a contact lens with a γ-polyglutamic acid coating.

[0067] Performance Verification

[0068] (1) Light transmittance test: The contact lenses of Examples 1 to 5 and Comparative Examples 1 to 2 were placed in a glass cuvette, and an appropriate amount of ultrapure water was added to cover the contact lenses. The contact lenses were then tested for light transmittance using a UV-visible photometer within the visible light wavelength range of 380 to 780 nm.

[0069] (2) Wettability test: The contact angles of the contact lenses of Examples 1 to 5 and Comparative Examples 1 to 2 were tested using a contact angle meter.

[0070] (3) Antibacterial test:

[0071] Escherichia coli antibacterial performance test: the concentration of 10 6 A CFU / mL Escherichia coli bacterial solution was evenly spread on MH agar medium. After the bacterial solution was completely absorbed by the agar, a drug-sensitive paper was applied. The drug-sensitive paper used was streptomycin and cefotaxime. Then, the contact lenses of Examples 1-5 and Comparative Examples 1-2 were attached to the agar medium. After incubation at 37°C for 24 hours, the antibacterial ring diameter was measured (antibacterial ring diameter = antibacterial ring outer diameter - test sample diameter) to test the antibacterial properties of the contact lenses.

[0072] Staphylococcus aureus antibacterial performance test: the concentration of 10 6 A Staphylococcus aureus bacterial solution with a concentration of CFU / mL was evenly spread on MH agar medium. After the bacterial solution was completely absorbed by the agar, a drug-sensitive paper strip containing streptomycin and cefotaxime was applied. The contact lenses of Examples 1-5 and Comparative Examples 1-2 were then attached to the agar medium. After incubation at 37°C for 24 hours, the antibacterial ring diameter (antibacterial ring diameter = antibacterial ring outer diameter - tested sample diameter) was measured to test the antibacterial properties of the contact lenses.

[0073] The above test results are shown in Table 1:

[0074] Table 1 Test results of Examples 1 to 5 and Comparative Examples 1 to 2

[0075]

[0076] As can be seen from Table 1, the present invention prepares a γ-polyglutamic acid inner layer and a hyaluronic acid surface layer through oxygen plasma activation, so that the contact lens has a gradient composite coating, which significantly improves the wettability and antibacterial properties of the contact lens and slightly reduces the transmittance.

[0077] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing a gradient composite coating for contact lenses, characterized in that: The steps include: (1) performing oxygen plasma activation on a contact lens substrate to obtain an activated substrate; (2) placing the activated substrate in a first coating solution to perform a first reaction to obtain a substrate with a first coating; The first coating solution is made of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride, N-hydroxysuccinimide and γ-polyglutamic acid; (3) placing the substrate with the first coating in a second coating solution to perform a second reaction, thereby obtaining a substrate with a gradient composite coating; The second coating solution is made of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride, N-hydroxysuccinimide and hyaluronic acid.

2. The method for preparing a gradient composite coating for contact lenses according to claim 1, wherein: In the step (1), the process parameters of the oxygen plasma treatment are: oxygen flow rate of 40 to 80 mL / min, power of 100 to 200 W, and time of 60 to 120 s.

3. The method for preparing a gradient composite coating for contact lenses according to claim 1 or 2, wherein: In the first coating solution, the concentration of γ-polyglutamic acid is 2-5 wt %.

4. The method for preparing a gradient composite coating for contact lenses according to claim 3, wherein: The temperature of the first reaction is 20-30° C., and the time is 10-30 minutes.

5. The method for preparing a gradient composite coating for contact lenses according to claim 2 or 4, wherein: In the second coating solution, the concentration of hyaluronic acid is 0.1-0.5 wt %.

6. The method for preparing a gradient composite coating for contact lenses according to claim 5, wherein: In the first coating solution and the second coating solution, the mass ratio of 1-(3-dimethylaminopropyl)-3-ethyldiimide hydrochloride to N-hydroxysuccinimide is independently 1 to 5:

1.

7. The method for preparing a gradient composite coating for contact lenses according to claim 4 or 6, characterized in that: The temperature of the second reaction is 20-30° C., and the time is 3-6 hours.

8. The method for preparing a gradient composite coating for contact lenses according to claim 7, wherein: After the second reaction is completed, dialysis is performed.

9. The gradient composite coating prepared by the method for preparing a gradient composite coating for contact lenses according to any one of claims 1 to 8.

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