Antibacterial contact lens silicon hydrogel composite material and preparation method thereof

Abstract

The invention relates to an antibacterial contact lens silicon hydrogel composite material and a preparation method thereof, and belongs to the technical field of silicon hydrogel materials, and the preparation method comprises the following steps: combining a natural compound with a biocompatible material to obtain a composite material; combining the composite material with a zwitterionic polymer to obtain an antibacterial reinforced material; the preparation method comprises the following steps: mixing a siloxane oligomer, an antibacterial reinforcing material, a hydrophilic monomer, a small molecular silicon monomer, a thermal initiator and a cross-linking agent, and carrying out polymerization reaction to obtain the antibacterial contact lens silicon hydrogel composite material, according to the technical scheme, the natural compound is combined with the biocompatible material, so that the antibacterial property and the stability of the silicon hydrogel composite material can be effectively improved; the composite material is combined with the zwitterionic polymer, so that the hydrophilicity and moisture retention of the silicon hydrogel composite material can be improved, the antibacterial performance of the silicon hydrogel composite material is further improved, and the comprehensive performance of the antibacterial contact lens silicon hydrogel composite material is generally improved.

Description

Technical Field

[0001] This invention belongs to the field of silicone hydrogel material technology, specifically, it relates to an antibacterial silicone hydrogel composite material for contact lenses and its preparation method. Background Technology

[0002] Contact lenses, also known as corneal contact lenses, are lenses worn directly on the cornea of ​​the eye to correct vision or protect the eyes. Soft contact lenses are popular among young people due to their excellent comfort and portability. The materials used in soft contact lenses are mainly divided into hydrogel and silicone hydrogel materials. Silicone hydrogel materials, in particular, contain organosilicon, which effectively improves the solubility and diffusion of oxygen within the material, thereby increasing its oxygen permeability. This allows oxygen from the lens surface to easily pass through the lens material into the cornea, reducing problems such as corneal edema caused by corneal hypoxia. Therefore, silicone hydrogel materials are widely used in the manufacture of contact lenses. To further improve the oxygen permeability of silicone hydrogel materials, siloxane components are often introduced. However, materials containing siloxane molecules are highly hydrophobic, which negatively impacts their biocompatibility. For example, they easily adsorb oils and proteins from tears, as well as bacteria and viruses, potentially triggering inflammatory reactions. Furthermore, they can cause "dry spots" on the lens surface, leading to a dry feeling and affecting wearing comfort. Therefore, there is an urgent need to develop an antibacterial silicone hydrogel composite material for contact lenses with superior overall performance to meet the current needs of the contact lens industry.

[0003] In existing technologies, antibacterial silicone hydrogel composite materials for contact lenses typically enhance their antibacterial properties by adding antibacterial ingredients (such as nano-silver, antibiotics, etc.). However, these antibacterial ingredients may induce corneal inflammation or damage ocular surface tissues during long-term wear, thereby increasing the risk of eye infections and limiting their widespread application in the field of contact lenses. Furthermore, traditional silicone hydrogel materials contain hydrophobic siloxane structures, resulting in insufficient surface hydrophilicity, which makes it difficult to keep the lens surface moist, causing discomfort symptoms such as dry eyes and foreign body sensation, significantly affecting wearing comfort. Summary of the Invention

[0004] The purpose of this invention is to provide an antibacterial silicone hydrogel composite material for contact lenses and its preparation method. The method involves combining a natural compound with a biocompatible material to obtain the composite material; combining the composite material with a zwitterionic polymer to obtain an antibacterial reinforcing material; and then mixing a siloxane oligomer, the antibacterial reinforcing material, a hydrophilic monomer, a small molecule silicon monomer, a thermal initiator, and a crosslinking agent, followed by a polymerization reaction to obtain the antibacterial silicone hydrogel composite material for contact lenses. The antibacterial reinforcing material exhibits good antibacterial effects, effectively improving the antibacterial performance and stability of the silicone hydrogel composite material. The final antibacterial silicone hydrogel composite material for contact lenses possesses good oxygen permeability, hydrophilicity, stability, and antibacterial properties, expanding the application range of silicone hydrogel composite materials and demonstrating good overall performance.

[0005] The technical problem this invention aims to solve is as follows: In the prior art, antibacterial silicone hydrogel composite materials for contact lenses typically enhance their antibacterial properties by adding antibacterial components (such as nano-silver, antibiotics, etc.). However, these antibacterial components may induce corneal inflammation or damage ocular surface tissues during long-term wear, thereby increasing the risk of eye infections and limiting their widespread application in the field of contact lenses. Furthermore, traditional silicone hydrogel materials, due to their hydrophobic siloxane structure, suffer from insufficient surface hydrophilicity, making it difficult to keep the lens surface moist, causing discomfort symptoms such as dry eyes and foreign body sensation, significantly affecting wearing comfort.

[0006] The objective of this invention can be achieved through the following technical solutions: A method for preparing an antibacterial silicone hydrogel composite material for contact lenses includes the following steps: S1: Composite materials are obtained by combining natural compounds with biocompatible materials; S2: Combining the composite material with a zwitterionic polymer yields an antibacterial reinforced material; S3: After mixing siloxane oligomers, antibacterial reinforcing materials, hydrophilic monomers, small molecule silicon monomers, thermal initiators and crosslinking agents, a polymerization reaction is carried out to obtain antibacterial contact lens silicone hydrogel composite materials.

[0007] Furthermore, step S1 specifically includes: The biocompatible material and acetic acid solution were mixed and stirred evenly at 75-85℃. Then, paraformaldehyde was added and stirring was continued for 25-35 minutes. Then, the natural compound was added and the mixture was stirred and reacted at 85-95℃ for 1-2 hours. After the reaction was completed, the mixture was cooled to room temperature, washed with deionized water, and finally vacuum dried at 45-55℃ to obtain the composite material.

[0008] In the above reaction process, the biocompatible material has an amino group, and the natural compound has a phenolic hydroxyl group. The active hydrogen atoms at the ortho and para positions of the phenolic hydroxyl group in the natural compound can undergo the Mannich reaction with the amino group in the biocompatible material in the presence of paraformaldehyde, thus combining the biocompatible material with the natural compound to obtain a composite material.

[0009] Furthermore, the mass ratio of the biocompatible material, acetic acid solution, paraformaldehyde, and natural compound is 0.8-1.2:40-50:1.8-2.2:2-2.4.

[0010] Furthermore, the biocompatible material is composed of chitosan and acrylate-polyethylene glycol-amino in a mass ratio of 1-1.2:0.7-0.8.

[0011] Furthermore, the natural compound is composed of resveratrol and curcumin in a mass ratio of 0.8-0.9:0.6-0.7.

[0012] Furthermore, step S2 specifically includes: The composite material from step S1 was added to an acetic acid solution and stirred until homogeneous. The mixture was then degassed with nitrogen for 25-35 minutes. Next, the zwitterionic polymer and catalyst were added, and the mixture was reacted for 11-13 hours under a nitrogen atmosphere and in a constant temperature water bath at 55-65°C. The pH of the system was adjusted to 6.7-7.3 with sodium hydroxide solution. The mixture was dialyzed with deionized water, and the acetic acid solution was removed by vacuum distillation. Finally, the mixture was freeze-dried to obtain the antibacterial reinforced material.

[0013] In the above reaction process, the chitosan molecular chain in the composite material has active hydrogen atoms, and the acrylate-polyethylene glycol-amino has carbon-carbon double bonds. In the presence of a catalyst, the active hydrogen atoms in the composite material are attacked to generate free radicals. The generated free radicals can initiate free radical grafting polymerization of the carbon-carbon double bonds in the acrylate-polyethylene glycol-amino and zwitterionic polymers, combining the composite material with the zwitterionic polymer to finally obtain an antibacterial reinforced material.

[0014] Furthermore, the mass ratio of the composite material, acetic acid solution, zwitterionic polymer, and catalyst is 0.8-1.2: 140-160: 2.8-3.2: 0.2-0.3.

[0015] Furthermore, the zwitterionic polymer is composed of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine in a mass ratio of 0.7-0.8:0.6-0.7.

[0016] Furthermore, the catalyst is ammonium persulfate.

[0017] Furthermore, the freeze-drying temperature is -50 to -40°C.

[0018] Further, in step S3, the mass ratio of the siloxane oligomer, modified antibacterial reinforcing material, hydrophilic monomer, small molecule silicon monomer, thermal initiator, and crosslinking agent is 25-35:10-15:50-60:8-12:0.8-1.2:1-1.4.

[0019] Furthermore, in step S3, the polymerization temperature of the polymerization reaction is 70-80℃, and the polymerization time is 16-20h.

[0020] Further, in step S3, the hydrophilic monomer is composed of N-vinylpyrrolidone, 2-hydroxyethyl methacrylate and N,N-dimethylacrylamide in a mass ratio of 0.9-1.1:0.6-0.8:0.5-0.7.

[0021] Further, in step S3, the small molecule silicon monomer is composed of methacryloyloxymethyltris(trimethylsiloxy)silane and 3-(methacryloyloxy)propyltrimethoxysilane mixed in a mass ratio of 1:1.

[0022] Further, in step S3, the thermal initiator is azobisisobutyronitrile or benzoyl peroxide.

[0023] Further, in step S3, the crosslinking agent is polyethylene glycol diacrylate or triethylene glycol dimethacrylate.

[0024] Further, in step S3, the method for preparing the siloxane oligomer includes the following steps: Octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, and bis-3-methylpropenyloxypropyltetramethyldisiloxane were added to toluene and stirred until homogeneous. Then, a polymerization inhibitor was added and stirred until homogeneous. Finally, a strong acidic cation exchange resin was added and the mixture was stirred at 50-60°C for 20-24 hours. After the reaction was completed, the mixture was filtered and toluene was removed by rotary evaporation to obtain the siloxane oligomer.

[0025] In the above reaction process, octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, and bis-3-methylpropenyloxypropyltetramethyldisiloxane are combined through a ring-opening polymerization reaction under the catalysis of a strongly acidic cation exchange resin, thereby combining octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, and bis-3-methylpropenyloxypropyltetramethyldisiloxane together to finally obtain siloxane oligomers.

[0026] Further, the mass ratio of the octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, bis-3-methylpropenyloxypropyltetramethyldisiloxane, toluene, polymerization inhibitor, and strong acid cation exchange resin is 19.8-20.2:1.3-1.7:0.8-1.2:190-210:0.02-0.04:0.4-0.5.

[0027] Furthermore, the polymerization inhibitor is p-methoxyphenol.

[0028] An antibacterial silicone hydrogel composite material for contact lenses prepared by the method described above.

[0029] The beneficial effects of this invention are: (1) In the technical solution of this invention, a composite material is obtained by combining natural compounds with biocompatible materials; the biocompatible material is composed of chitosan and acrylate-polyethylene glycol-amino mixture; both have good biocompatibility, and chitosan also has a certain antibacterial effect, which can improve the antibacterial performance of the silicone hydrogel composite material. acrylate-polyethylene glycol-amino can enhance the hydrophilicity and moisture retention of the silicone hydrogel composite material. By mixing chitosan and acrylate-polyethylene glycol-amino, the two play a synergistic role, which can effectively improve the biocompatibility, hydrophilicity, oxygen permeability and antibacterial performance of the silicone hydrogel composite material. Improving wearing comfort and safety; the natural compound is composed of a mixture of resveratrol and curcumin, both of which have good antioxidant and antibacterial effects. Combining resveratrol and curcumin can also play a synergistic antibacterial role, further improving the antibacterial performance and stability of the silicone hydrogel composite material, and reducing inflammation caused by wearing contact lenses, thus improving wearing comfort and safety; combining the natural compound with biocompatible materials can not only improve the oxygen permeability, hydrophilicity and antibacterial properties of the silicone hydrogel composite material, but also provide reaction sites for subsequent reactions, further enhancing the overall performance of the silicone hydrogel composite material.

[0030] (2) In the technical solution of the present invention, an antibacterial reinforcing material is obtained by combining the composite material with a zwitterionic polymer; the zwitterionic polymer is composed of a mixture of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine. 2-methacryloyloxyethyl phosphoric acid choline contains highly hydrophilic phosphoric acid choline groups, which can form a stable hydration layer on the surface of the material, greatly improving the material's moisturizing ability and lubricity, and reducing the possibility of bacterial adhesion, thus enhancing the antibacterial properties of the silicone hydrogel material. Methacryloxyethyl sulfobetaine also has good hydrophilicity and can reduce protein deposition in tears, thereby improving the anti-fouling and anti-contamination properties of the silicone hydrogel composite material. Protein adsorption was assessed by mixing 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine, which exhibited a good synergistic effect, further improving the oxygen permeability, hydrophilicity, stability, and antibacterial properties of the silicone hydrogel composite material, thus enhancing wearing comfort and safety. This mixture also provided reaction sites for subsequent reactions. Furthermore, a polymerization reaction was carried out by mixing siloxane oligomers, antibacterial reinforcing materials, hydrophilic monomers, small-molecule silicon monomers, thermal initiators, and crosslinking agents to obtain an antibacterial contact lens silicone hydrogel composite material. The antibacterial reinforcing material significantly improved the overall performance of the silicone hydrogel composite material, enhancing the safety of contact lens wear and reducing the risk of eye infections.

[0031] (3) In the technical solution of the present invention, an antibacterial reinforcing material is obtained by combining natural compounds with biocompatible materials and then with zwitterionic polymers. The siloxane oligomer, antibacterial reinforcing material, hydrophilic monomer, small molecule silicon monomer, thermal initiator and crosslinking agent are mixed and polymerized to obtain an antibacterial contact lens silicone hydrogel composite material. The obtained antibacterial contact lens silicone hydrogel composite material not only has good oxygen permeability and hydrophilicity, but also effectively improves the antibacterial performance and stability of the silicone hydrogel composite material, improves the wearing comfort and safety of contact lenses, expands the application range of silicone hydrogel composite material, and has good overall performance. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] The specific parameters of the raw materials used in this invention are as follows: Chitosan, CAS No.: 9012-76-4, Trade Code: M81003, provided by Shanghai Mairui Biochemical Technology Co., Ltd.; Acrylate-polyethylene glycol-amino, CAS No.: 956493-68-8, Trade Code: BD01402434, provided by Shanghai Bide Pharmaceutical Technology Co., Ltd.; Resveratrol, CAS No.: 501-36-0, Trade Code: M17777, provided by Shanghai Mairui Biochemical Technology Co., Ltd.; Curcumin, CAS No.: 458-37-7, Trade Code: M 17074, provided by Shanghai Mairui Biochemical Technology Co., Ltd.; 2-Methacryloxyethylphosphocholine, CAS No.: 67881-98-5, Trade No.: M742532, provided by Shanghai Maclean Biochemical Technology Co., Ltd.; Methacryloxyethylsulfobetaine, CAS No.: 3637-26-1, Trade No.: M838595, provided by Shanghai Maclean Biochemical Technology Co., Ltd.; Strong acid cation exchange resin, brand name: D001, provided by Jiangsu Haopeng Energy Saving and Environmental Protection Technology Co., Ltd.

[0034] Example 1 The specific steps for preparing antibacterial silicone hydrogel composite materials for contact lenses are as follows: S1: The biocompatible material, acetic acid solution, paraformaldehyde, and natural compound were mixed in a mass ratio of 0.8:40:1.8:2. The mixture was stirred at 75°C until homogeneous, then paraformaldehyde was added and stirring was continued for 25 minutes. The natural compound was then added and the mixture was stirred at 85°C for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and washed three times with deionized water (each time the mass of deionized water was 40% of the mass of the acetic acid solution). Finally, the mixture was vacuum dried at 45°C for 12 hours to obtain the composite material. The biocompatible material was composed of chitosan and acrylate-polyethylene glycol-amino in a mass ratio of 1:0.7; the natural compound was composed of resveratrol and curcumin in a mass ratio of 0.8:0.6. S2: According to the mass ratio of composite material, acetic acid solution, zwitterionic polymer, and ammonium persulfate of 0.8:140:2.8:0.2, the composite material from step S1 was added to 1wt% acetic acid solution and stirred evenly. After degassing with nitrogen for 25 min, zwitterionic polymer and ammonium persulfate were added. The mixture was reacted for 13 h under nitrogen atmosphere protection and constant temperature water bath at 55 °C. The pH of the system was adjusted to 6.7 with 1 mol / L sodium hydroxide solution. The mixture was then transferred to a dialysis bag (molecular weight cutoff of 12 kDa) and dialyzed with deionized water for 3 days. The acetic acid solution was removed by vacuum distillation at 40 °C. Finally, the mixture was freeze-dried at -50 °C for 24 h to obtain the antibacterial reinforcing material. The zwitterionic polymer was composed of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine in a mass ratio of 0.7:0.6. S3: The following mixtures of siloxane oligomers, modified antibacterial reinforcing materials, hydrophilic monomers, small molecule silicon monomers, azobisisobutyronitrile (AIB), and triethylene glycol dimethacrylate were mixed uniformly according to a mass ratio of 25:10:50:8:0.8:1, and then subjected to a polymerization reaction at 70℃ for 20 hours to obtain an antibacterial contact lens silicone hydrogel composite material. The hydrophilic monomers were composed of N-vinylpyrrolidone, 2-hydroxyethyl methacrylate, and N,N-dimethylacrylamide in a mass ratio of 0.9:0.6:0.5; the small molecule silicon monomers were composed of methacryloyloxymethyltris(trimethylsiloxy)silane and 3-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1. The preparation method of siloxane oligomers includes the following steps: The following steps were performed: Octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, bis-3-methylpropenyloxypropyltetramethyldisiloxane, toluene, p-methoxyphenol, and a strong acid cation exchange resin were added to toluene in a mass ratio of 19.8:1.3:0.8:190:0.02:0.4. The mixture was stirred until homogeneous, then p-methoxyphenol was added and stirred until homogeneous again. Finally, the strong acid cation exchange resin was added, and the mixture was stirred at 50°C for 24 hours. After the reaction was completed, the mixture was filtered, and toluene was removed by rotary evaporation at 50°C to obtain the siloxane oligomer.

[0035] Example 2 The specific steps for preparing antibacterial silicone hydrogel composite materials for contact lenses are as follows: S1: The biocompatible material, acetic acid solution, paraformaldehyde, and natural compound were mixed in a mass ratio of 1:45:2:2.2. The mixture was stirred at 80°C until homogeneous, then paraformaldehyde was added and stirring was continued for 30 minutes. The natural compound was then added and the mixture was stirred at 90°C for 1.5 hours. After the reaction, the mixture was cooled to room temperature and washed three times with deionized water (each wash containing 40% of the acetic acid solution mass). Finally, the mixture was vacuum dried at 50°C for 12 hours to obtain the composite material. The biocompatible material was composed of chitosan and acrylate-polyethylene glycol-amino compounds in a mass ratio of 1.1:0.75; the natural compound was composed of resveratrol and curcumin in a mass ratio of 0.85:0.65. S2: According to the mass ratio of composite material, acetic acid solution, zwitterionic polymer, and ammonium persulfate of 1:150:3:0.25, the composite material from step S1 was added to 1wt% acetic acid solution and stirred evenly. After degassing with nitrogen for 30 min, zwitterionic polymer and ammonium persulfate were added. The mixture was reacted for 12 h in a nitrogen atmosphere and a constant temperature water bath at 60 °C. The pH of the system was adjusted to 7 with 1 mol / L sodium hydroxide solution. The mixture was then transferred to a dialysis bag (molecular weight cutoff of 12 kDa) and dialyzed with deionized water for 3 days. The acetic acid solution was removed by vacuum distillation at 45 °C. Finally, the mixture was freeze-dried at -45 °C for 24 h to obtain the antibacterial reinforcing material. The zwitterionic polymer was composed of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine in a mass ratio of 0.75:0.65. S3: Following a mass ratio of 30:12:55:10:1:1.2 for siloxane oligomers, modified antibacterial reinforcing materials, hydrophilic monomers, small molecule silicon monomers, benzoyl peroxide, and polyethylene glycol diacrylate, a polymerization reaction was carried out at 75℃ for 18 hours to obtain an antibacterial contact lens silicone hydrogel composite material. The hydrophilic monomers were composed of N-vinylpyrrolidone, 2-hydroxyethyl methacrylate, and N,N-dimethylacrylamide in a mass ratio of 1:0.7:0.6; the small molecule silicon monomers were composed of methacryloyloxymethyltris(trimethylsiloxy)silane and 3-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1. The preparation method of siloxane oligomers includes the following steps: The following steps were performed: Octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, bis-3-methylpropenyloxypropyltetramethyldisiloxane, toluene, p-methoxyphenol, and a strong acid cation exchange resin were added to toluene in a mass ratio of 20:1.5:1:200:0.03:0.45 and stirred until homogeneous. Then p-methoxyphenol was added and stirred until homogeneous. Finally, the strong acid cation exchange resin was added and the mixture was stirred at 55°C for 22 hours. After the reaction was completed, the mixture was filtered, and toluene was removed by rotary evaporation at 55°C to obtain the siloxane oligomer.

[0036] Example 3 The specific steps for preparing antibacterial silicone hydrogel composite materials for contact lenses are as follows: S1: The biocompatible material, acetic acid solution, paraformaldehyde, and natural compound were mixed in a mass ratio of 1.2:50:2.2:2.4. The mixture was stirred at 85°C until homogeneous, then paraformaldehyde was added and stirring was continued for 35 minutes. The natural compound was then added and the mixture was stirred at 95°C for 1 hour. After the reaction was completed, the mixture was cooled to room temperature and washed three times with deionized water (each wash containing 40% of the acetic acid solution mass). Finally, the mixture was vacuum dried at 55°C for 12 hours to obtain the composite material. The biocompatible material was composed of chitosan and acrylate-polyethylene glycol-amino compounds in a mass ratio of 1.2:0.8; the natural compound was composed of resveratrol and curcumin in a mass ratio of 0.9:0.7. S2: According to the mass ratio of composite material, acetic acid solution, zwitterionic polymer, and ammonium persulfate of 1.2:160:3.2:0.3, the composite material from step S1 was added to 1wt% acetic acid solution and stirred evenly. After degassing with nitrogen for 35 min, zwitterionic polymer and ammonium persulfate were added. The mixture was reacted for 11 h under nitrogen atmosphere and constant temperature water bath at 65 °C. The pH of the system was adjusted to 7.3 with 1 mol / L sodium hydroxide solution. The mixture was then transferred to a dialysis bag (molecular weight cutoff of 12 kDa) and dialyzed with deionized water for 3 days. The acetic acid solution was removed by vacuum distillation at 50 °C. Finally, the mixture was freeze-dried at -40 °C for 24 h to obtain the antibacterial reinforcing material. The zwitterionic polymer was composed of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine in a mass ratio of 0.8:0.7. S3: The following mixtures of siloxane oligomers, modified antibacterial reinforcing materials, hydrophilic monomers, small-molecule silicon monomers, azobisisobutyronitrile (AIB), and triethylene glycol dimethacrylate were mixed uniformly according to a mass ratio of 35:15:60:12:1.2:1.4. The mixtures were then subjected to a polymerization reaction at 80℃ for 16 hours to obtain an antibacterial contact lens silicone hydrogel composite material. The hydrophilic monomers were composed of N-vinylpyrrolidone, 2-hydroxyethyl methacrylate, and N,N-dimethylacrylamide in a mass ratio of 1.1:0.8:0.7. The small-molecule silicon monomers were composed of methacryloyloxymethyltris(trimethylsiloxy)silane and 3-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1. The preparation method of siloxane oligomers includes the following steps: The following steps were performed: Octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, bis-3-methylpropenyloxypropyltetramethyldisiloxane, toluene, p-methoxyphenol, and a strong acid cation exchange resin were added to toluene in a mass ratio of 20.2:1.7:1.2:210:0.04:0.5. The mixture was stirred until homogeneous, then p-methoxyphenol was added and stirred until homogeneous again. Finally, the strong acid cation exchange resin was added, and the mixture was stirred at 60°C for 20 hours. After the reaction was completed, the mixture was filtered, and toluene was removed by rotary evaporation at 60°C to obtain the siloxane oligomer.

[0037] Comparative Example 1 The difference between this comparative example and Example 3 is that, in the preparation of the antibacterial contact lens silicone hydrogel composite material, in step S1, the biocompatible material is replaced with chitosan by an equal mass, while the remaining steps and raw materials are the same as in Example 3. S1: Chitosan, acetic acid solution, paraformaldehyde, and natural compound were mixed in a mass ratio of 1.2:50:2.2:2.4. The mixture was stirred at 85°C until homogeneous. Paraformaldehyde was then added and the mixture was stirred for another 35 minutes. The natural compound was then added and the mixture was stirred at 95°C for 1 hour. After the reaction was completed, the mixture was cooled to room temperature and washed three times with deionized water (each wash containing 40% of the mass of the acetic acid solution). Finally, the mixture was vacuum dried at 55°C for 12 hours to obtain the composite material. The natural compound was composed of resveratrol and curcumin in a mass ratio of 0.9:0.7.

[0038] Comparative Example 2 The difference between this comparative example and Example 3 is that, in the preparation of the antibacterial contact lens silicone hydrogel composite material, in step S1, the biocompatible material is replaced by acrylate-polyethylene glycol-amino in equal mass, while the remaining steps and raw materials are the same as in Example 3. S1: According to the mass ratio of acrylate-polyethylene glycol-amino, acetic acid solution, paraformaldehyde, and natural compound of 1.2:50:2.2:2.4, acrylate-polyethylene glycol-amino and 2wt% acetic acid solution were mixed and stirred evenly at 85℃. Then, paraformaldehyde was added and stirring was continued for 35 min. Then, the natural compound was added and the reaction was stirred at 95℃ for 1 h. After the reaction was completed, it was cooled to room temperature and washed three times with deionized water (each time the mass of deionized water was 40% of the mass of acetic acid solution). Finally, it was vacuum dried at 55℃ for 12 h to obtain the composite material. The natural compound was composed of resveratrol and curcumin mixed in a mass ratio of 0.9:0.7.

[0039] Comparative Example 3 The difference between this comparative example and Example 3 is that, in the preparation of the antibacterial contact lens silicone hydrogel composite material, in step S1, the natural compound is replaced with resveratrol by an equal mass, while the remaining steps and raw materials are the same as in Example 3. S1: The biocompatible material, acetic acid solution, paraformaldehyde, and resveratrol were mixed in a mass ratio of 1.2:50:2.2:2.4. The mixture was stirred at 85°C until homogeneous, then paraformaldehyde was added and stirring was continued for 35 minutes. Resveratrol was then added and the mixture was stirred at 95°C for 1 hour. After the reaction was completed, the mixture was cooled to room temperature and washed three times with deionized water (each wash containing 40% of the mass of the acetic acid solution). Finally, the mixture was vacuum dried at 55°C for 12 hours to obtain the composite material. The biocompatible material was composed of chitosan and acrylate-polyethylene glycol-amino in a mass ratio of 1.2:0.8.

[0040] Comparative Example 4 The difference between this comparative example and Example 3 is that, in the preparation of the antibacterial contact lens silicone hydrogel composite material, in step S1, the natural compound is replaced by curcumin in equal mass, while the remaining steps and raw materials are the same as in Example 3. S1: The biocompatible material, acetic acid solution, paraformaldehyde, and curcumin were mixed in a mass ratio of 1.2:50:2.2:2.4. The mixture was stirred evenly at 85°C, paraformaldehyde was added, and stirring was continued for 35 minutes. Then curcumin was added, and the mixture was stirred at 95°C for 1 hour. After the reaction was completed, the mixture was cooled to room temperature and washed three times with deionized water (each time the mass of deionized water was 40% of the mass of the acetic acid solution). Finally, the mixture was vacuum dried at 55°C for 12 hours to obtain the composite material. The biocompatible material was composed of chitosan and acrylate-polyethylene glycol-amino in a mass ratio of 1.2:0.8.

[0041] Comparative Example 5 The difference between this comparative example and Example 3 is that, in the preparation of the antibacterial contact lens silicone hydrogel composite material, in step S2, the zwitterionic polymer is replaced by 2-methacryloyloxyethyl phosphocholine in equal mass, while the remaining steps and raw materials are the same as in Example 3. S2: According to the mass ratio of composite material, acetic acid solution, 2-methacryloyloxyethyl phosphocholine, and ammonium persulfate of 1.2:160:3.2:0.3, the composite material from step S1 was added to 1wt% acetic acid solution and stirred evenly. The mixture was degassed with nitrogen for 35 min, and then 2-methacryloyloxyethyl phosphocholine and ammonium persulfate were added. The mixture was reacted for 11 h under nitrogen atmosphere and constant temperature water bath at 65 °C. The pH of the system was adjusted to 7.3 with 1 mol / L sodium hydroxide solution. The mixture was then transferred to a dialysis bag (molecular weight cutoff of 12 kDa) and dialyzed with deionized water for 3 days. The acetic acid solution was removed by vacuum distillation at 50 °C. Finally, the mixture was freeze-dried at -40 °C for 24 h to obtain the antibacterial reinforcing material.

[0042] Comparative Example 6 The difference between this comparative example and Example 3 is that, in the preparation of the antibacterial contact lens silicone hydrogel composite material, in step S2, the zwitterionic polymer is replaced by an equal mass of methacryloyl ethyl sulfobetaine, while the remaining steps and raw materials are the same as in Example 3. S2: According to the mass ratio of composite material, acetic acid solution, methacryloyl ethyl sulfobetaine, and ammonium persulfate of 1.2:160:3.2:0.3, the composite material from step S1 was added to 1 wt% acetic acid solution and stirred evenly. The mixture was degassed with nitrogen for 35 min, and then methacryloyl ethyl sulfobetaine and ammonium persulfate were added. The mixture was reacted for 11 h under nitrogen atmosphere and constant temperature water bath at 65 °C. The pH of the system was adjusted to 7.3 with 1 mol / L sodium hydroxide solution. The mixture was then transferred to a dialysis bag (molecular weight cutoff of 12 kDa) and dialyzed with deionized water for 3 days. The acetic acid solution was removed by vacuum distillation at 50 °C. Finally, the mixture was freeze-dried at -40 °C for 24 h to obtain the antibacterial reinforcing material.

[0043] Comparative Example 7 The difference between this comparative example and Example 3 is that, in the preparation of the antibacterial contact lens silicone hydrogel composite material, in step S2, the composite material is directly mixed with the zwitterionic polymer, while the remaining steps and raw materials are the same as in Example 3. S2: According to the mass ratio of composite material, acetic acid solution, and zwitterionic polymer of 1.2:160:3.2, the composite material from step S1 was added to 1wt% acetic acid solution and stirred evenly. After degassing with nitrogen for 35 min, the zwitterionic polymer was added, and the reaction was carried out at room temperature for 11 h. The pH of the system was adjusted to 7.3 with 1 mol / L sodium hydroxide solution, and then transferred to a dialysis bag (molecular weight cutoff of 12 kDa). Dialysis was performed with deionized water for 3 days. The acetic acid solution was removed by vacuum distillation at 50 °C. Finally, the mixture was freeze-dried at -40 °C for 24 h to obtain the antibacterial reinforcing material. The zwitterionic polymer was composed of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine in a mass ratio of 0.8:0.7.

[0044] The oxygen permeability coefficient, water content, and antibacterial properties of the antibacterial contact lens silicone hydrogel composite materials prepared in Examples 1-3 and Comparative Examples 1-7 were tested. Oxygen permeability coefficient and water content were tested according to GB / T 11417.7-2012 "Ophthalmic Optical Contact Lenses Part 7: Test Methods for Physicochemical Properties". Antibacterial properties were tested: (1) Staphylococcus aureus bacterial solution with a concentration of 106 CFU / mL was dipped in a cotton swab and evenly spread on MH agar medium. After the bacterial solution was completely absorbed by the agar, the antibacterial contact lens silicone hydrogel composite materials prepared in Examples 1-3 and Comparative Examples 1-7 with a diameter of 10 mm were respectively attached to the agar medium and cultured at 37℃ for 24 h; (2) Staphylococcus aureus bacterial solution with a concentration of 106 CFU / mL was dipped in a cotton swab and evenly spread on MH agar medium. After the bacterial solution was completely absorbed by the agar, the antibacterial contact lens silicone hydrogel composite materials prepared in Examples 1-3 and Comparative Examples 1-7 with a diameter of 10 mm were respectively attached to the agar medium and cultured at 37℃ for 24 h; (2) Staphylococcus aureus bacterial solution with a concentration of 106 CFU / mL was dipped in a cotton swab and evenly spread on MH agar medium. 6 CFU / mL of Escherichia coli bacterial suspension was evenly spread onto NZYM broth medium. After the bacterial suspension was completely absorbed by the agar, antibacterial contact lens silicone hydrogel composite materials prepared in Examples 1-3 and Comparative Examples 1-7, with a diameter of 10 mm, were respectively attached to the agar medium and incubated at 37°C for 24 h. The diameter of the antibacterial ring was measured for both test schemes (antibacterial ring diameter = outer diameter of antibacterial ring - diameter of the tested sample). The test results are shown in Table 1 below: Table 1 Performance parameters of antibacterial silicone hydrogel composite materials for contact lenses prepared in Examples 1-3 and Comparative Examples 1-7

[0045] As shown in Table 1 above, and comparing Comparative Examples 1-4 with Example 3, in step S1, replacing the biocompatible material with chitosan or acrylate-polyethylene glycol-amino, or replacing the natural compound with resveratrol or curcumin, resulted in a poorer test result compared to Example 3. This indicates that the biocompatible material composed of chitosan and acrylate-polyethylene glycol-amino has a synergistic effect, effectively improving the oxygen permeability and hydrophilicity of the silicone hydrogel composite material, and significantly enhancing its antibacterial properties and stability. The natural compound composed of resveratrol and curcumin also has a synergistic antibacterial effect, effectively improving the antibacterial properties of the silicone hydrogel composite material, and further enhancing its oxygen permeability and hydrophilicity. Comparing Comparative Examples 5-7 and Example 3, it can be seen that in step S2, replacing the zwitterionic polymer with 2-methacryloyloxyethyl phosphorocholine or methacryloylethyl sulfobetaine by equal mass, or directly mixing the composite material with the zwitterionic polymer, and finally preparing the antibacterial contact lens silicone hydrogel composite material, the test results are worse than those of Example 3. This indicates that the zwitterionic polymer composed of 2-methacryloyloxyethyl phosphorocholine and methacryloylethyl sulfobetaine has a synergistic effect, which can effectively improve the oxygen permeability and hydrophilicity of the silicone hydrogel composite material, and has a good influence on the antibacterial properties of the silicone hydrogel composite material. Combining the composite material with the zwitterionic polymer through chemical means can enhance the bonding force between the two, further improving the antibacterial properties, oxygen permeability, and hydrophilicity of the silicone hydrogel composite material.

[0046] As shown in Table 1 above, the antibacterial silicone hydrogel composite materials for contact lenses prepared in Examples 1-3, compared to those prepared in Comparative Examples 1-7, achieve better performance. Examples 1-3 combine natural compounds with biocompatible materials, and then with zwitterionic polymers to obtain antibacterial reinforcing materials. The antibacterial composite materials obtained in Examples 1-3 are prepared by mixing siloxane oligomers, antibacterial reinforcing materials, hydrophilic monomers, small molecule silicon monomers, thermal initiators, and crosslinking agents, followed by polymerization. The antibacterial silicone hydrogel composite materials prepared in Examples 1-7 do not meet the performance requirements. This indicates that the antibacterial silicone hydrogel composite materials prepared in this invention have better oxygen permeability and hydrophilicity, as well as good antibacterial properties and stability, expanding the application range of silicone hydrogel composite materials and exhibiting better overall performance.

[0047] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0048] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined by the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing an antibacterial silicone hydrogel composite material for contact lenses, characterized in that, Includes the following steps: S1: Composite materials are obtained by combining natural compounds with biocompatible materials; S2: Combining the composite material with a zwitterionic polymer yields an antibacterial reinforced material; S3: After mixing siloxane oligomers, antibacterial reinforcing materials, hydrophilic monomers, small molecule silicon monomers, thermal initiators and crosslinking agents, a polymerization reaction is carried out to obtain antibacterial contact lens silicone hydrogel composite materials.

2. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 1, characterized in that, Step S1 is as follows: The biocompatible material and acetic acid solution were mixed and stirred evenly at 75-85℃. Then, paraformaldehyde was added and stirring was continued for 25-35 minutes. Then, the natural compound was added and the mixture was stirred and reacted at 85-95℃ for 1-2 hours. After the reaction was completed, the mixture was cooled to room temperature, washed with deionized water, and finally vacuum dried at 45-55℃ to obtain the composite material.

3. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 2, characterized in that, The biocompatible material is composed of chitosan and acrylate-polyethylene glycol-amino in a mass ratio of 1-1.2:0.7-0.

8.

4. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 2, characterized in that, The natural compound is composed of resveratrol and curcumin in a mass ratio of 0.8-0.9:0.6-0.

7.

5. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 1, characterized in that, Step S2 is as follows: The composite material from step S1 was added to an acetic acid solution and stirred until homogeneous. The mixture was then degassed with nitrogen for 25-35 minutes. Next, the zwitterionic polymer and catalyst were added, and the mixture was reacted for 11-13 hours under a nitrogen atmosphere and in a constant temperature water bath at 55-65°C. The pH of the system was adjusted to 6.7-7.3 with sodium hydroxide solution. The mixture was dialyzed with deionized water, and the acetic acid solution was removed by vacuum distillation. Finally, the mixture was freeze-dried to obtain the antibacterial reinforced material.

6. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 5, characterized in that, The zwitterionic polymer is composed of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine in a mass ratio of 0.7-0.8:0.6-0.

7.

7. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 1, characterized in that, In step S3, the polymerization temperature of the polymerization reaction is 70-80℃, and the polymerization time is 16-20h.

8. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 1, characterized in that, The hydrophilic monomer is composed of N-vinylpyrrolidone, 2-hydroxyethyl methacrylate and N,N-dimethylacrylamide in a mass ratio of 0.9-1.1:0.6-0.8:0.5-0.

7.

9. The method for preparing an antibacterial contact lens silicone hydrogel composite material according to claim 1, characterized in that, The method for preparing the siloxane oligomer includes the following steps: Octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, and bis-3-methylpropenyloxypropyltetramethyldisiloxane were added to toluene and stirred until homogeneous. Then, a polymerization inhibitor was added and stirred until homogeneous. Finally, a strong acidic cation exchange resin was added and the mixture was stirred at 50-60°C for 20-24 hours. After the reaction was completed, the mixture was filtered and toluene was removed by rotary evaporation to obtain the siloxane oligomer.

10. An antibacterial silicone hydrogel composite material for contact lenses prepared by the method according to any one of claims 1-9.

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