Cornea surface protective agent and preparation method thereof

Abstract

The invention relates to the technical field of medical supplies for ophthalmology, and particularly discloses a cornea surface protective agent based on a compound polysaccharide synergistic effect and a preparation method of the cornea surface protective agent. The protective agent comprises chitosan quaternary ammonium salt, trehalose and recombinant human collagen as core active components, and a specific buffer system is supplemented. Through the specific proportioning combination of the core components, the protective agent can quickly form a stable and light-transmitting protective film on the cornea surface, and provides the comprehensive effects of long-acting moisturizing, epithelial repair promotion and inflammation resistance. Experiments show that the moisturizing time of the protective agent can reach more than 90 minutes, the light transmittance exceeds 98%, and corneal epithelium injury repair can be remarkably accelerated. The invention further provides a preparation method of the protective agent, and the preparation method is simple in process and suitable for industrial production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ophthalmic medical supplies, in particular to a corneal surface protective agent and a preparation method thereof. BACKGROUND

[0002] In ophthalmic surgery, the eye cannot close naturally due to the use of specula, and the cornea is easily dried in the air, leading to epithelial cell damage, decreased transparency, and affecting the surgical field. Balanced salt solution (BSS) is a commonly used corneal moisturizer, but it evaporates easily and needs to be repeatedly irrigated during surgery, which interferes with the surgical process and increases patient discomfort.

[0003] In the prior art, attempts have been made to use high molecular materials such as hydroxypropyl methyl cellulose (HPMC), chondroitin sulfate or sodium hyaluronate to improve the moisturizing performance. For example, Chinese patent application CN113876800A discloses a corneal protective agent, which comprises: hydroxypropyl methyl cellulose with a viscosity of 5 mPa·s to 200,000 mPa·s and / or chondroitin sulfate with a molecular weight of 2 to 50,000, anti-inflammatory substances, and buffer. The corneal protective agent of the present application can protect the corneal surface during surgery, maintain the corneal surface wet for a certain period of time, and maintain good corneal transparency to provide a good surgical field. At the same time, it can also reduce the risk of postoperative corneal epithelial dysfunction and reduce postoperative complications. The corneal protective agent contains HPMC and / or chondroitin sulfate, but its formula is relatively traditional, and there is still room for improvement in long-term moisturizing, rapid film-forming property and promoting tissue repair.

[0004] For example, Chinese patent CN104083396B discloses a corneal surface protective agent, and also relates to a preparation method of the corneal surface protective agent, and an application range of the product. The corneal surface protective agent comprises the following components: sodium hyaluronate with a molecular weight of 100,000 D to 2,000,000 D, a concentration range of 5 mg / ml to 200 mg / ml; or chondroitin sulfate with a molecular weight of 5 KD to 100,000 D, a concentration range of 5 mg / ml to 200 mg / ml; or chitosan with a molecular weight of 5 KD to 2,000,000 D, a concentration range of 5 mg / ml to 200 mg / ml. Compared with the traditional preservation solution which is only applied to preserve ex vivo corneal tissue, the corneal surface protective agent prepared by the method of the present application can be applied in clinical surgery, and can be applied to the corneal surface during surgery, can maintain the moisture and light transmission of the cornea for a period of time, greatly reduces the frequency of water points during surgery, accelerates the surgical progress, and improves the patient comfort. It focuses on ex vivo corneal preservation (such as SMILE lens protective solution), and cannot well meet the stringent requirements of in-situ protection on transparency, adhesion and biocompatibility.

[0005] Therefore, there is an urgent need in the art to develop a new type of corneal surface protective agent that can quickly form a stable, high-transparency protective film, provide long-term moisturizing, and has the functions of promoting epithelial repair and anti-inflammatory to optimize the surgical effect. SUMMARY

[0006] In view of the deficiencies of the prior art, the purpose of the present application is to provide a corneal surface protective agent and a preparation method thereof, which is a novel and synergistic corneal surface protective agent that can quickly form a stable protective film on the corneal surface, provide long-term moisturizing effect far superior to the prior art, and promote corneal epithelial repair, while having good transparency and biocompatibility.

[0007] The above invention purpose of the present application is realized by the following technical scheme: A corneal surface protective agent, consisting of the following components: Chitosan quaternary ammonium salt: molecular weight 100,000-500,000 Dalton, concentration 0.5-5 mg / mL; Trehalose: concentration 10-100 mg / mL; Recombinant human collagen: molecular weight 100,000-300,000 Dalton, concentration 0.2-5 mg / mL; Buffer, the buffer comprises Tris-HCl buffer pair, concentration 10-50 mmol / L, and contains NaCl 5.0-9.0 g / L, KCl 0.1-0.5 g / L; Wherein, the mass ratio of the chitosan quaternary ammonium salt, trehalose and recombinant human collagen is 1: (0.5-2) : (0.2-1).

[0008] As a further technical scheme of the present application: the degree of deacetylation of the chitosan quaternary ammonium salt is ≥90%, and the degree of substitution is ≥80%.

[0009] As a further technical scheme of the present application: the recombinant human collagen is type III collagen.

[0010] As a further technical scheme of the present application: it further comprises ectoine, concentration 0.1-5 mg / mL.

[0011] As a further technical scheme of the present application: the pH value of the buffer is 7.2-7.6, and the osmotic pressure is 280-310 mOsm / L.

[0012] As a further technical scheme of the present application: its dosage form is a ready-to-use gel, which is a liquid at room temperature and is converted into a gel state within 10-20 seconds at body temperature after being dropped into the eye.

[0013] The application further discloses a preparation method of the corneal surface protective agent. The chitosan quaternary ammonium salt is dissolved in part of the buffer solution and stirred until completely dissolved to obtain solution A; The trehalose and the recombinant human collagen are dissolved in another part of the buffer solution and stirred until completely dissolved to obtain solution B; Solution B is slowly added into solution A under uniform stirring, and mixed uniformly; The pH value and the osmotic pressure of the mixed solution are adjusted to a specified range; The solution is filtered through a 0.22 mu m microporous filter membrane, sterilized and aseptically packaged.

[0014] As a further technical scheme of the application, the buffer solution is preheated to 40-50 DEG C when the chitosan quaternary ammonium salt is dissolved.

[0015] The application further discloses application of the corneal surface protective agent in preparation of medical devices or drugs for protecting corneas in ophthalmic surgeries.

[0016] As a further technical scheme of the application, the ophthalmic surgery comprises cataract surgery, corneal refractive surgery and vitrectomy.

[0017] To achieve the above object, the application adopts the following technical scheme. The corneal surface protective agent of the application is characterized in that the chitosan quaternary ammonium salt, the trehalose and the recombinant human collagen are combined in a specific manner, and the mass ratio of the three is limited.

[0018] The chitosan quaternary ammonium salt is a cationic polysaccharide, has good film forming property, antibacterial property and moisturizing property, and is selected in the application to have a specific molecular weight (100-500 thousand Dalton) and a deacetylation degree (greater than or equal to 90%) so as to be more easily dissolved in water and to enhance adhesion to the negatively charged corneal surface.

[0019] The trehalose is a natural disaccharide, has excellent moisturizing property and stability, and can protect cells in a stress state (such as dryness).

[0020] The recombinant human collagen, especially the type III collagen, is an important component of the corneal stroma, has good biocompatibility, and can promote epithelial cell migration and wound healing.

[0021] When the three components are combined in a specific mass ratio (chitosan quaternary ammonium salt: trehalose: recombinant human collagen = 1: (0.5-2): (0.2-1)), a significant synergistic effect is exhibited. They can quickly build a dense and light-transmitting three-dimensional network structure on the corneal surface through electrostatic interaction, hydrogen bonding, etc. The structure has a very strong water-locking ability and can simulate the extracellular matrix environment to provide a good repair platform for epithelial cells.

[0022] Preferably, the protective agent can also contain ectoine, which is a highly effective cell protective agent that can further enhance the stability of the protective agent in the surgical environment and the protective effect on corneal cells.

[0023] The buffer system is preferably a Tris-HCl buffer pair supplemented with necessary electrolytes to make the pH and osmotic pressure of the protective agent similar to that of tears, thereby reducing irritation to the eye.

[0024] In summary, compared with the prior art, the present application has at least one of the following beneficial technical effects: Ingredient innovation and synergistic effect: chitosan quaternary ammonium salt, trehalose and recombinant human collagen are combined in a specific manner for intraoperative corneal protection for the first time, and through synergistic effect, the dual functions of long-acting moisturizing (≥90 minutes) and promoting epithelial repair are achieved.

[0025] Excellent film-forming property and transparency: the protective agent can form a uniform, stable and highly light-transmitting (light transmittance > 98%) protective film on the corneal surface within 10-20 seconds, greatly improving the surgical field of view.

[0026] Good biocompatibility: the use of biocompatible materials such as recombinant human collagen significantly reduces the risk of potential irritation and immunogenicity.

[0027] Comprehensive protection function: physical barrier, moisturizing, promoting repair and certain antibacterial and anti-inflammatory ability, providing comprehensive protection. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described below in conjunction with the embodiments of the present application; obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0029] Embodiment 1: The formula for preparing the corneal surface protective agent is: Chitosan quaternary ammonium salt (molecular weight 300,000, degree of deacetylation 92%): 2 mg / mL; Trehalose: 50 mg / mL; Recombinant human collagen type III (molecular weight 200,000): 1 mg / mL; Ectoin: 1 mg / mL; Buffer: Tris-HCl 20 mmol / L, NaCl 8.0 g / L, KCl 0.3 g / L; pH: 7.4; Osmotic pressure: 295 mOsm / L; The preparation method is as follows: Dissolve the chitosan quaternary ammonium salt in part of the preheated buffer solution (45°C), stir until clear, and obtain solution A.

[0030] Dissolve trehalose, recombinant human collagen, and ectoin in another part of the buffer solution, stir until completely dissolved, and obtain solution B.

[0031] Slowly add solution B to solution A under magnetic stirring, and continue stirring for 30 minutes to mix uniformly.

[0032] Adjust the pH of the mixture to 7.4 with dilute HCl or NaOH, and fine-tune the osmotic pressure to 295 mOsm / L if necessary.

[0033] Filter sterilize with a 0.22 μm microporous filter, and aseptically dispense into single-dose eye drop bottles.

[0034] Example 2: The formula for preparing the corneal surface protective agent is as follows: Chitosan quaternary ammonium salt (molecular weight 100,000, degree of deacetylation 90%): 0.5 mg / mL; Trehalose: 10 mg / mL; Recombinant human collagen type III (molecular weight 200,000): 0.2 mg / mL; Ectoin: 0.1 mg / mL; Buffer: Tris-HCl 10 mmol / L, NaCl 5.0 g / L, KCl 0.1 g / L; pH: 7.2; Osmotic pressure: 280 mOsm / L; The preparation method is as follows: Dissolve the chitosan quaternary ammonium salt in part of the preheated buffer solution (40°C), stir until clear, and obtain solution A.

[0035] Dissolve trehalose, recombinant human collagen, and ectoin in another part of the buffer solution, stir until completely dissolved, and obtain solution B.

[0036] Solution B was slowly added to solution A under magnetic stirring, and the mixture was stirred for 30 minutes to ensure uniformity.

[0037] The pH of the mixture was adjusted to 7.2 using dilute HCl or NaOH, and the osmotic pressure was fine-tuned to 280 mOsm / L using NaCl if necessary.

[0038] The solution was filtered through a 0.22 μm microporous filter to remove bacteria, and was then aseptically divided into single-dose eye drop bottles. Example 3: The formula for preparing the corneal surface protective agent is as follows: Chitosan quaternary ammonium salt (molecular weight 500,000, degree of deacetylation 95%): 5 mg / mL Trehalose: 100 mg / mL Recombinant human collagen type III (molecular weight 200,000): 5 mg / mL Ectoine: 5 mg / mL Buffer: Tris-HCl 50 mmol / L, NaCl 9.0 g / L, KCl 0.5 g / L pH: 7.6 Osmotic pressure: 310 mOsm / L The preparation method is as follows: Chitosan quaternary ammonium salt was dissolved in part of the preheated buffer (50°C) and stirred until clear to obtain solution A.

[0039] Trehalose, recombinant human collagen, and ectoine were dissolved in another part of the buffer and stirred until completely dissolved to obtain solution B.

[0040] Solution B was slowly added to solution A under magnetic stirring, and the mixture was stirred for 30 minutes to ensure uniformity.

[0041] The pH of the mixture was adjusted to 7.6 using dilute HCl or NaOH, and the osmotic pressure was fine-tuned to 310 mOsm / L using NaCl if necessary.

[0042] The solution was filtered through a 0.22 μm microporous filter to remove bacteria, and was then aseptically divided into single-dose eye drop bottles.

[0043] Comparative Example 1: The formula for a corneal protective agent according to Chinese patent application CN113876800A was used.

[0044] Comparative Example 2: The formula for this comparative example did not contain recombinant human collagen, and the remaining formula and preparation method were the same as those of Example 1.

[0045] Test Example: Performance Evaluation The protective agents prepared in Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2 were tested, and the test results are shown in Table 1: Table 1, Summary of Experimental Data

[0046] Moisture retention time: In a simulated surgical environment, 0.1 mL of protective agent was added to the surface of an ex vivo pig cornea, and the time for the corneal surface to completely dry was recorded. Results: The moisture retention time was 95 ± 5 minutes, which was significantly longer than that of Comparative Example 1 (CN113876800A formulation, about 50 minutes) and Comparative Example 2 (formulation without recombinant human collagen, about 70 minutes).

[0047] Transmittance: The transmittance of the protective agent in the visible light band (400-700 nm) was measured using a UV-Vis spectrophotometer. Results: The average transmittance was >98%, indicating excellent optical performance.

[0048] Epithelial cell migration experiment (wound healing assay): A human corneal epithelial cell line was used to compare the migration speed in a medium containing the protective agent extract of Example 1. Results: The cell migration speed was significantly faster compared to the control group, indicating that it can promote corneal epithelial repair.

[0049] Comparative Example 1 (containing only HPMC and chondroitin sulfate, referring to CN113876800A) and Comparative Example 2 (without recombinant human collagen) were set up for comparison with Example 1 of the present application. The results showed that the present application had significant advantages in moisture retention time, film formation speed and repair promotion ability. The corneal surface protective agent provided by the present application, through unique ingredient combination and proportioning, achieved excellent intraoperative protection performance and had good clinical application prospects.

[0050] Firstly, the protective agent achieved a breakthrough improvement in core performance indicators, especially in its ultra-long moisture retention time and excellent optical performance. Experimental data showed that the protective agent could maintain a wet state on the corneal surface for more than 95 minutes in a simulated surgical environment, significantly better than the control sample (about 50 minutes). At the same time, its transmittance was more than 98%, ensuring the clarity of the surgical field. This significant improvement in comprehensive performance directly solves the core pain points of repeated irrigation and blurred vision due to corneal drying during surgery.

[0051] Secondly, this protective agent achieves functional integration through the synergistic effect between its components, surpassing the traditional design concept of single efficacy. In a specific ratio, the chitosan quaternary ammonium salt, trehalose, and recombinant human collagen in its formula not only form a stable three-dimensional network water-locking structure but also exhibit the function of promoting corneal epithelial cell migration (24-hour migration rate increased to 85%). This means that while providing physical protection, the product can also actively participate in tissue repair, achieving a functional leap from "passive protection" to "active repair." This integration of multiple functions brings unexpected technological results.

[0052] Finally, the technical effects of this protective agent directly translate into significant clinical advantages. In animal experiments, surgeries using this protective agent resulted in faster corneal epithelial healing and milder inflammatory responses. This validates that its "instant gel" formulation (forming a film within 10-20 seconds) can reduce the number of interventions, improve surgical efficiency, and lower the risk of postoperative complications in real surgical scenarios. This improvement in clinical benefits, supported by laboratory data, powerfully demonstrates the substantial contribution this invention makes to existing technologies.

[0053] In conclusion, this corneal surface protectant is not a simple combination of known ingredients; rather, it produces a synergistic effect through a specific formulation, achieving significant progress in key performance, functional integration, and clinical value, thus meeting the inventiveness requirements for patent granting. The principle of this invention is as follows: This invention relates to the field of ophthalmic medical supplies technology, specifically disclosing a corneal surface protectant based on the synergistic effect of complex polysaccharides and its preparation method. This protectant contains chitosan quaternary ammonium salt, trehalose, and recombinant human collagen as core active ingredients, supplemented by a specific buffering system. Through a specific combination of the above core ingredients, this protectant can rapidly form a stable, light-transmitting protective film on the corneal surface, providing long-lasting moisturizing, promoting epithelial repair, and anti-inflammatory effects. Experiments show that this protectant has a moisturizing time of over 90 minutes, a light transmittance exceeding 98%, and can significantly accelerate the repair of corneal epithelial damage. This invention also provides a preparation method for this protectant, which is simple and suitable for industrial production.

[0054] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A corneal surface protectant, characterized in that, It consists of the following components: Chitosan quaternary ammonium salt: molecular weight 100,000-500,000 Daltons, concentration 0.5-5 mg / mL; Trehalose: concentration 10-100 mg / mL; Recombinant human collagen: molecular weight 100,000-300,000 Daltons, concentration 0.2-5 mg / mL; The buffer solution comprises a Tris-HCl buffer pair at a concentration of 10-50 mmol / L and contains 5.0-9.0 g / L NaCl and 0.1-0.5 g / L KCl; The mass ratio of chitosan quaternary ammonium salt, trehalose and recombinant human collagen is 1: (0.5-2): (0.2-1).

2. The corneal surface protectant according to claim 1, characterized in that, The degree of deacetylation of the chitosan quaternary ammonium salt is ≥90%, and the degree of substitution is ≥80%.

3. The corneal surface protectant according to claim 1, characterized in that, The recombinant human collagen is type III collagen.

4. A corneal surface protectant according to claim 1, characterized in that, It also contains ectoine at a concentration of 0.1-5 mg / mL.

5. A corneal surface protectant according to claim 1, characterized in that, The buffer solution has a pH of 7.2-7.6 and an osmotic pressure of 280-310 mOsm / L.

6. A corneal surface protectant according to claim 1, characterized in that, Its dosage form is an instant gel, which is a liquid at room temperature and transforms into a gel state within 10-20 seconds at body temperature after being instilled into the eye.

7. A method for preparing a corneal surface protectant as described in any one of claims 1-6, characterized in that, Includes the following steps: Dissolve chitosan quaternary ammonium salt in a portion of the buffer solution and stir until completely dissolved to obtain solution A; Dissolve trehalose and recombinant human collagen in another portion of the buffer solution and stir until completely dissolved to obtain solution B; Under constant stirring, solution B is slowly added to solution A and mixed thoroughly. Adjust the pH and osmotic pressure of the mixture to the specified range; Sterilized by filtration through a 0.22μm microporous membrane, and aseptically packaged.

8. The method for preparing the corneal surface protectant according to claim 7, characterized in that, When dissolving chitosan quaternary ammonium salt, the buffer solution should be preheated to 40-50℃.

9. The use of the corneal surface protectant according to any one of claims 1-6 in the preparation of a medical device or medicament for protecting the cornea during ophthalmic surgery.

10. The use of the corneal surface protectant according to claim 9 in the preparation of medical devices or pharmaceuticals for protecting the cornea during ophthalmic surgery, characterized in that, The ophthalmic surgeries include cataract surgery, corneal refractive surgery, and vitrectomy.

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