A contact lens care solution

Abstract

The application relates to a contact lens care solution, which is composed of the following components in percentage by weight: 0.001-1% of cationic guar gum; 0.5-15% of an osmotic pressure regulator; 0.1-5% of a pH regulator; 0.05-1% of a surfactant; and the balance of water; wherein the surfactant is a mixture composed of alkyl polyglycoside and poloxamer. The cationic guar gum in the formula has good biocompatibility and no irritation to the eyes. The chemical performance is stable, has good lubricating performance, can be better combined with the anion groups of the lens, better lubricates the lens, promotes the lens to carry more water, keeps the oxygen permeability of the lens stable, and effectively reduces the deposition of proteins on the lens. By adding alkyl polyglycoside and poloxamer as the surfactant, the lubricating and moisturizing performance of the care solution can be further improved, and the bacteriostatic performance of the care solution can be further improved in cooperation with the cationic guar gum.

Description

Technical Field

[0001] This application relates to the field of contact lens care solutions, and more specifically, to a contact lens care solution. Background Technology

[0002] Contact lenses are broadly classified into soft and rigid contact lenses. Soft contact lenses are mostly made from monomers such as 2-hydroxyethyl methacrylate (HEMA), especially water-based soft contact lenses, which are widely used due to their minimal foreign body sensation and comfortable fit. However, changes in the surface structure of contact lenses can significantly alter their wearing comfort, thus affecting the wearer in various ways. The wearing comfort of contact lenses is greatly influenced by the interaction between the lens and the tear film. Therefore, for a good wearing comfort, it is important to ensure that the lens surface is covered by tear film. However, because water-based soft contact lenses absorb water from the tear film during wear to compensate for insufficient water content caused by evaporation, this can lead to thinning of the tear film. This results in further promoting dryness, leading to poor wearing comfort and a risk of damage to the corneal and conjunctival surfaces due to mechanical friction. In addition, the increasing prevalence of office automation equipment such as computers and the effects of air conditioning in recent years have contributed to dry eye syndrome, especially evaporative dry eye syndrome, and other external factors that cause dryness of the contact lens and ocular surface, which is also a concern. Drying of the contact lens causes waste from the tear film to adhere to the lens surface, resulting in poor wearing comfort and visual field. Therefore, inhibiting lens drying and stabilizing the tear film layer are crucial for maintaining a good wearing comfort.

[0003] Classic soft hydrophilic contact lenses are mostly polymerized from poly(hydroxyethyl methacrylate) or combined with other monomers, leaving a certain number of anions such as hydroxyl groups on their surface or inside. Some formulations, to further enhance wearing comfort, introduce or increase substances such as methacrylic acid, giving the material more anionic hydrophilic groups such as carboxyl groups. The presence of these anionic hydrophilic groups presents several problems:

[0004] 1. Multifunctional care products mainly use cationic bactericides such as polyaminopropyl biguanide and polyquaternium salt. The presence of anionic groups on the lens will affect the actual effectiveness of the care product on the lens, and will also cause the cationic bactericide to accumulate on the lens. The subsequent continuous release will have an adverse effect on the eyes.

[0005] 2. The protein components in tears mostly carry a positive charge. The negative charge on the lens surface will exacerbate the amount and intensity of protein deposition and increase the difficulty of cleaning. Protein deposition will lead to a decrease in the water content of the lens, a decrease in oxygen permeability, and induce a series of eye diseases.

[0006] Therefore, new solutions are urgently needed to address the problems with existing contact lens care products. Summary of the Invention

[0007] In order to overcome the shortcomings of existing contact lens care solutions, this application provides a contact lens care solution containing cationic guar gum.

[0008] To achieve the above technical objectives, this application adopts the following technical solution:

[0009] A contact lens care solution comprises the following components by weight percentage:

[0010] Cationic guar gum 0.001-1%;

[0011] Osmotic pressure regulator 0.5-15%;

[0012] pH adjuster 0.1-5%;

[0013] Surfactant 0.05-1%;

[0014] Water balance;

[0015] The surfactant is a mixture of alkyl glycosides and poloxamer.

[0016] Preferably, the structural formula of the cationic guar gum is:

[0017]

[0018] Preferably, the molecular weight of the cationic guar gum is 1,000-300,000.

[0019] Preferably, the cationic guar gum content is 0.001-0.1% by mass.

[0020] More preferably, the cationic guar gum content is 0.01-0.05% by mass.

[0021] Preferably, the mass ratio of the alkyl glycoside to poloxamer is 1:(1-10).

[0022] Preferably, the mass ratio of the cationic guar gum to the alkyl glycoside is 1:1.

[0023] Preferably, the osmotic pressure of the nursing solution is 240-340 mOsm / kg, and the pH value is in the range of 6-8.

[0024] Preferably, the osmotic pressure regulator is selected from one or more of sodium chloride, potassium chloride, and magnesium chloride.

[0025] Preferably, the pH adjuster is selected from one or more of disodium hydrogen phosphate, sodium dihydrogen phosphate, boric acid, borax, citric acid, and sodium citrate.

[0026] Cationic guar gum is a water-soluble polymer, chemically known as guar hydroxypropyltrimethylammonium chloride. This positively charged modified guar gum can interact with negatively charged substances, thereby enhancing its retention effect. For example, classic soft hydrophilic contact lenses are often polymerized from poly(hydroxyethyl methacrylate) or combined with other monomers, leaving a certain number of hydroxyl and other anions on their surface or inside. The contact lens solution of this application, by adding cationic guar gum, can better bind with the anionic groups of the lens: promoting the internal carrying of more water, maintaining stable oxygen permeability of the lens; forming a more stable hydrophilic film layer on the lens surface, making wearing more comfortable, and effectively reducing protein deposits.

[0027] The contact lens solution provided in this application can be used in two ways: first, as a preservation solution during the lens manufacturing process, it is packaged together with the lens in the initial packaging; second, as a lubricant or eye drops, it can be used when wearing lenses or when experiencing discomfort. Detailed Implementation

[0028] The present application will be further described in detail below with reference to the embodiments.

[0029] A contact lens care solution, by weight percentage, has the following formula:

[0030] Cationic guar gum 0.001-1%;

[0031] Osmotic pressure regulator 0.5-15%;

[0032] pH adjuster 0.1-5%;

[0033] Surfactant 0.05-1%;

[0034] Water balance;

[0035] The surfactant is a mixture of alkyl glycosides and poloxamer.

[0036] The above raw material components are stirred and dissolved evenly in a conventional manner to obtain the contact lens care solution.

[0037] Example

[0038] Examples 1-8

[0039] A contact lens care solution is composed of the following raw material components: cationic guar gum, osmotic pressure regulator, pH regulator, surfactant, and water.

[0040] The cationic guar gum has a molecular weight of 220,000; the osmotic pressure regulator is sodium chloride; the pH regulator is boric acid and borax; the surfactants are alkyl glycoside 0810 and poloxamer 127; and the osmotic pressure of each embodiment is controlled within the range of 240-340 mOsm / kg.

[0041] The dosage of each of the above components is shown in Table 1.

[0042] Table 1. Components and their weight percentages in Examples 1-8 (Unit: %); Total: 100g

[0043] Cationic guar gum 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.01 Alkyl glycoside 0810 0.05 0.04 0.06 0.05 0.05 0.05 0.05 0.01 Polosham 127 0.2 0.2 0.2 0.04 0.05 0.5 0.55 0.04 Sodium chloride 7.5 7.5 7.5 7.5 7.5 7.5 7.5 7.5 Boric acid 6.4 6.4 6.4 6.4 6.4 6.4 6.4 6.4 Borax 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 water 84.9 84.91 84.89 85.06 85.05 84.6 84.55 85.14 pH value 7.4 7.4 7.4 7.4 7.4 7.4 7.4 7.4

[0044] Comparing the test results of Example 1 with those of Examples 2-3, it can be seen that when the mass ratio of cationic guar gum to alkyl glycoside is 1:1, the nursing solution has the best antibacterial and bactericidal effect.

[0045] Comparing the test results of Example 1 with those of Examples 4-7, it can be seen that when the mass ratio of cationic guar gum to poloxamer is 1:(1-10), the care solution has the best self-cleaning and wetting effect.

[0046] Comparative Example

[0047] Comparative Example 1

[0048] A contact lens care solution, which differs from Example 1 in that the formulation of Comparative Example 1 does not contain cationic guar gum, and the water content is increased to 85.4%.

[0049] Comparative Example 2

[0050] A contact lens care solution, which differs from Example 1 in that the formulation of Comparative Example 1 does not contain alkyl glycosides, and the content of poloxamer is increased to 0.25%.

[0051] Comparative Example 3

[0052] A contact lens care solution, which differs from Example 1 in that the formulation of Comparative Example 1 does not contain poloxamer, and the content of alkyl glycosides is increased to 0.25%.

[0053] Performance testing

[0054] The contact lens solutions prepared in the above embodiments and comparative examples were used as test samples for performance testing.

[0055] I. Antibacterial Performance Test

[0056] Preparation of bacterial suspension: Remove the test tubes of Staphylococcus aureus, Escherichia coli, and Candida albicans frozen at -20°C and thaw at 37°C. After complete thawing, use a sterile pipette to transfer the frozen solution into 15ml centrifuge tubes, add the corresponding culture medium, and subculture overnight at 37°C. The next day, centrifuge the bacterial suspension at 3000 rpm for 5 minutes, add phosphate buffer, and mix well. Repeat the above steps. Finally, dilute with sterile PBS to a final concentration of approximately 10%. 5 cfu / m.

[0057] Test Procedure: Take three sterile 15mL test tubes, add an appropriate amount of the test solution to each tube, then add 500μL of the prepared bacterial suspension. Use a sterile pipette to mix the solutions thoroughly. After 4 hours of incubation, use a pipette to mix the solutions thoroughly again, and transfer 1mL of the mixture to 5mL of neutralizing agent solution, mixing well. After 10 minutes, take 100μL of the neutralized solution and inoculate it onto appropriate amounts of nutrient agar (suitable for Staphylococcus aureus and Escherichia coli) and Sabouraud dextrose agar (suitable for Candida albicans). Prepare two plates from each tube and incubate at 30–35℃ for three days. Calculate the inhibition rate using the viable cell count method.

[0058] Antibacterial inhibition rate (LR) = [Log 10 (I)-Log 10 (F)]

[0059] Where I represents the colony count in the control group (PBS), and F represents the colony count after exposure to the test solution.

[0060] The test results are recorded in Table 2 below.

[0061] II. Self-cleaning ability test

[0062] Prepare a standard physiological saline solution: 8.3 mg / mL NaCl, 5.993 mg / mL Na2HPO4·12H2O, and 0.528 mg / mL Na2HPO4·2H2O. Dissolve the solutions in purified water. The solution pH is -7.4 ± 0.1, and the osmotic pressure is 310 mOsm / kgH2O.

[0063] To prepare artificial tears: Dissolve 1.9 mg / mL lysozyme, 0.2 mg / mL BSA (albumin: Sigma), and 0.1 mg / mL γ-Globulin (Sigma) in standard physiological saline and adjust the pH to 7.0 with HCl and NaOH.

[0064] Establish a standard curve: Take 0 ml, 0.1 ml, 0.3 ml, 0.5 ml, 0.7 ml, 0.9 ml, 1.0 ml, 1.2 ml, 1.5 ml, and 2.0 ml of artificial tears respectively and put them into 10 ml volumetric flasks. Dilute to the mark with standard physiological saline and mix thoroughly. Measure the absorbance value A at 280 nm on a UV spectrophotometer. Based on the absorbance value A of the nine solutions, plot the relationship between absorbance A and protein concentration to obtain the standard curve.

[0065] Test procedure: Place the lens (Class IV, Ocufilcon E, 65% water content) in a stoppered vial, add 2 ml of artificial tears, the total protein content is C, tighten the cap, and place it in an incubator at 37℃±1℃ for 65 hours. After incubation, clean the lens surface with standard physiological saline, add the cleaning solution to the stoppered vial, transfer the artificial tears to a 10 ml volumetric flask and make up to volume. Measure the absorbance at 280 nm on a UV spectrophotometer, calculate the protein adsorption rate on the standard curve, and record the results in Table 2.

[0066] III. Lubrication and Moisturizing Performance Test

[0067] 1. Lubrication performance test: A reciprocating micro-tribometer is used to study the friction coefficient of the lens: a protein-coated glass disk mounted on a rotating disk simulates the shape of the eyelid surface.

[0068] Coefficient of friction (CoF) = FF / FN

[0069] Where FF is the frictional force between the lens surface and the friction disk surface, and FN is the normal load. The linear velocity includes the physiologically relevant eyelid velocity range: 0.1 mm / s corresponds to the eyelid velocity during incomplete blinking; 8 cm / s corresponds to the eyelid velocity during complete blinking.

[0070] The linear velocity of the friction disk is v = r * RPM * 0.10472

[0071] Where v is the linear velocity in m / s; r is the radius in m; RPM is the angular velocity in RPM (revolutions per minute); 0.10472 is the ratio of 2π / 60 RPM to rad / s.

[0072] The normal force applied to the lens is 2mN.

[0073] The friction coefficients of the test lens at 0 min and 60 min are recorded in Table 2 below.

[0074] 2. Moisturizing performance test:

[0075] The contact angle can be used to measure the moisturizing performance of a contact lens solution. The better the moisturizing performance, the smaller the contact angle, and the more comfortable it is to wear.

[0076] Test Method: The contact angle of the contact solution with the lens was measured using the static drop method. The lens was immersed in the contact solution to be tested, and after 12 hours, the contact angle was measured using a surface tension meter. The contact solution was drawn up with a syringe, and a droplet was suspended at the needle tip and brought into contact with the lens. A photograph was taken immediately after contact, and the forward and backward contact angles were calculated from the images.

[0077] Table 2 Performance Test Results

[0078]

[0079]

[0080] Comparing the antibacterial test results of Example 1 and Comparative Examples 1-2, it can be seen that when cationic guar gum and alkyl glycosides are used alone, their antibacterial effect is less than 90% or equivalent. However, when the two are used in combination, they have a highly efficient synergistic effect.

[0081] Comparing the antibacterial test results of Example 1 with those of Examples 2-3, it can be seen that when the mass ratio of cationic guar gum to alkyl glycoside is 1:10, the nursing solution has the best antibacterial and bactericidal effect.

[0082] Comparing the self-cleaning test results of Example 1, Comparative Examples 1 and 3, it can be seen that cationic guar gum plays a decisive role in the protein adsorption rate of the contact lens solution. The addition of poloxamer can also give the contact lens solution a certain self-cleaning ability, which reduces its protein adsorption rate to a certain extent. When the two are used in combination, they have a highly efficient synergistic self-cleaning effect, resulting in lenses treated with the contact lens solution having a lower protein adsorption rate.

[0083] Comparing the self-cleaning test results of Example 1 with those of Examples 4-7, it can be seen that the care solution has the best self-cleaning effect when the mass ratio of cationic guar gum to poloxamer is 1:(1-10).

[0084] Comparing the lubrication test results of Example 1 and Comparative Example 1, it can be seen that when cationic guar gum is added to the system, the friction coefficient decreases significantly. The friction coefficient at 60 minutes is still comparable to the initial value when no cationic guar gum is added. This indicates that the care solution containing cationic guar gum is adsorbed onto the lens surface through charge action, forming a certain thickness and a stable moisturizing and lubricating isolation layer.

[0085] Comparing the wetting test results of Example 1 and Comparative Examples 1-3, it can be seen that the addition of cationic guar gum, alkyl glycosides, and poloxamer can all improve the wetting and moisturizing performance of the care solution, and the combination of the three can further improve the wetting and moisturizing performance of the care solution.

[0086] In summary, this application provides a novel contact lens solution containing cationic guar gum, alkyl glycosides, and poloxamer. As a contact lens solution, it can be used in two ways: firstly, as a preservative during lens manufacturing, it is packaged together with the lenses in the initial packaging; secondly, as a lubricant or eye drops, it is used when wearing lenses or experiencing discomfort. Cationic guar gum has good biocompatibility and is non-irritating to the eyes. Its chemical properties are stable, it has good lubricating properties, and it can better bind to the anionic groups of the lens, thus better lubricating the lens: promoting the internal carrying capacity of the lens, maintaining stable oxygen permeability, and effectively reducing protein deposits on the lens. By adding alkyl glycosides and poloxamer as surfactants, not only can the lubricating and moisturizing properties of the solution be further improved, but they can also synergistically enhance the antibacterial properties of the solution with cationic guar gum.

[0087] The above description is merely a preferred embodiment of this application. The scope of protection of this application is not limited to the above embodiments. All technical solutions falling within the scope of this application's concept are within the scope of protection of this application. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of this application should also be considered within the scope of protection of this application.

Claims

1. A contact lens care solution, characterized in that, It consists of the following components by weight percentage: Cationic guar gum 0.01-0.05%; Osmotic pressure regulator 7.5%; pH adjuster 7.3%; Surfactant 0.05-0.6%; Water balance; The surfactant is a mixture of alkyl glycoside and poloxamer, wherein the mass ratio of alkyl glycoside to poloxamer is 1:(1-10); The mass ratio of cationic guar gum to alkyl glycoside is 1:

1.

2. The contact lens solution according to claim 1, characterized in that, The structural formula of the cationic guar gum is: ，n≥1。 3. The contact lens solution according to claim 2, characterized in that, The molecular weight of the cationic guar gum is 1,000-300,000.

4. The contact lens solution according to claim 1, characterized in that, The osmotic pressure of the nursing solution is 240-340 mOsm / kg, and the pH value ranges from 6 to 8.

5. The contact lens solution according to claim 1, characterized in that, The osmotic pressure regulator is selected from one or more of sodium chloride, potassium chloride, and magnesium chloride.

6. The contact lens solution according to claim 1, characterized in that, The pH adjuster is selected from one or more of disodium hydrogen phosphate, sodium dihydrogen phosphate, boric acid, borax, citric acid, and sodium citrate.

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