Preparation method and application of hydrogel antibacterial coating with hole brush structure

Abstract

The invention discloses a preparation method of a hydrogel antibacterial coating with a hole brush structure and application of the hydrogel antibacterial coating in the field of artificial joints, the surface of a substrate is enabled to be rich in hydroxyl active functional groups through plasma equipment, and the hydrogel coating with a double-network structure is prepared based on ultraviolet-induced surface polymerization. A Gemini amphiphilic polymer monomer and an SBMA amphoteric monomer are jointly grafted to a hydrogel coating, a polymer brush can be evenly distributed on the surface of the double-network hydrogel coating and in pores of the double-network hydrogel coating, a polymer brush / hydrogel composite coating is formed, and the hydrophilic lubricity of the surface of a substrate can be improved; falling is not prone to occurring, and environmental pollution is prevented; a'contact 'sterilization mode is achieved, and the antibacterial performance is provided; when applied to the field of artificial joints, the lubricating property of an artificial joint material can be improved, the stress buffering effect is achieved, the physiological impact load resistance of the artificial joint is improved, the service life is prolonged, bacterial infection can be effectively prevented through the antibacterial property, and the life hygiene safety of patients and medical staff is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of manual shutdown, and more particularly to a preparation method and application of a hydrogel antibacterial coating with a hole brush structure. Background Art

[0002] As the load-bearing tissue of human joints, articular cartilage can effectively reduce the friction and impact of the joint surface during repeated movements of the human body, and has the function of lubrication and shock absorption. The structure of this highly hydrated connective tissue is very unique. It is a porous elastic material rich in water and has a certain shape and hardness. Its distribution has an orderly interlayer structure, which can provide high support strength and energy dissipation mechanism, so that cartilage has excellent load-bearing and impact resistance.

[0003] Hydrogel is a kind of soft and wet polymer material with a three-dimensional network structure formed by chemical or physical cross-linking. It has a high degree of similarity to biological organisms and is one of the materials closest to biological structures. Therefore, it is an ideal articular cartilage replacement material. Its potential advantages are: (1) Many synthetic polymer gels have shown good biocompatibility; (2) They have similar properties to natural cartilage. In addition to structural similarities, they also show swelling, viscoelasticity and considerable compression stiffness, and can withstand certain loading cycles; (3) After modification, they can simulate the natural lubrication mechanism in cartilage tissue.

[0004] However, compared with biological soft tissues, traditional hydrogels have high water content, and the chemical crosslinkers are unevenly dispersed during the preparation process, which often causes network structure defects. Stress concentration is easily generated during use, leading to problems such as fragility and poor mechanical properties. Due to the high water content, uneven network structure, inefficient energy dissipation mechanism and single network unit function, traditional hydrogels generally have problems such as poor mechanical strength and poor deformation self-recovery performance, which seriously restricts their practical application. Therefore, how to improve the mechanical properties of traditional hydrogels has always been the primary problem to be solved in the field of functional polymer materials research.

[0005] Ideal artificial joint cartilage must not only meet the requirements of appropriate water content and biocompatibility, but also provide sufficiently high mechanical strength and excellent lubrication properties. However, the improvement of the mechanical strength of hydrogel bionic cartilage materials is often at the expense of the densification of the network microstructure, which leads to a decrease in surface hydration and poor lubrication properties. In addition, the colonization and reproduction of bacteria on the surface of medical materials is the main cause of nosocomial infection, especially the infection related to the surface of implanted / interventional catheters, which not only has high morbidity and mortality, but also potentially threatens the life safety of patients and medical staff. Summary of the invention

[0006] In order to solve one of the above-mentioned technical problems, the present invention provides a method for preparing a hydrogel antibacterial coating with a porous brush structure. The antibacterial coating is composited by a hydrogel coating and a polymer brush coating, and has a porous brush structure. It can improve the hydrophilic lubricity of the attached surface, reduce the friction performance of the material, and have ultra-high antibacterial performance. It is very suitable for application in the field of artificial joints to improve the comfort and service life of artificial joints. It can also effectively resist bacteria and prevent bacterial infection, thereby improving the life and health safety of patients and medical staff.

[0007] In order to solve one of the above technical problems, one of the inventive objectives of the present invention is to provide a technical solution:

[0008] Provided is a method for preparing a hydrogel antibacterial coating having a pore brush structure, comprising the following steps:

[0009] Step 1, pre-treating the surface of the substrate with a plasma surface treatment machine so that the surface is rich in hydroxyl active functional groups;

[0010] Step 2, immersing the pretreated substrate obtained in step 1 into a hydrogel monomer aqueous solution containing a hydrophilic initiator; the hydrogel monomer aqueous solution is an aqueous solution of acrylamide and vinyl alcohol; surface polymerization is initiated by ultraviolet light to modify a double network hydrogel coating on the surface of the substrate;

[0011] Step 3, grafting Geminized amphiphilic polymer monomers and SBMA amphiphilic monomers onto the surface of the hydrogel coating obtained in step 2 to form a polymer brush / hydrogel composite coating.

[0012] The technical principles and beneficial effects of the above technical solution are as follows:

[0013] The substrate can be made of many materials, and its surface can be pretreated using plasma equipment to make its surface rich in hydroxyl active functional groups. After the substrate surface is rich in hydroxyl active functional groups, a hydrogel coating with a "double network" structure can be prepared based on ultraviolet light-induced surface polymerization through step 2. After the high-strength and high-toughness hydrogel coating is attached to the substrate surface, the Geminized amphiphilic polymer monomer and the SBMA amphiphilic monomer are co-grafted onto the hydrogel coating through step 3. The polymer brush will be evenly distributed on the coating surface and its pores of the double-network hydrogel to form a polymer brush / hydrogel composite coating. Constructing a polymer brush with multiple functions on the surface of the hydrogel substrate to prepare a polymer brush / hydrogel composite coating with a "pore brush" structure can improve the hydrophilic lubricity of the substrate material surface. Compared with the physical coating method, this covalent bonding method can make the hydrogel coating more firmly bonded to the substrate, not easy to fall off, and prevent environmental pollution; in addition, the polymer brush coating has a "contact" sterilization method, which can provide ultra-high antibacterial performance and help reduce bacterial resistance. By preparing the substrate into different shapes, the hydrogel antibacterial coating of the present invention can be applied to different application fields with its hydrophilic lubricity, improved antibacterial properties and other performance effects, and the application range will be very wide. The surface initiated polymerization method and the two sterilization mechanisms of the polymer brush in the above technical scheme have been disclosed in the literature Tuning ice nucleation with counteriongs on polyelectrolyte brush surfaces, Sci. Adv. 2016; 2: e1600345 and the literature Permanent, non-leaching antibacterial surfaces-2: how high density cationic surfaces kill bacterial, Biomaterials 28 (2007) 4870–4879).

[0014] Preferably, the Geminized amphiphilic polymer monomer is 1,3-bis(N,N,N-dimethyloctylammonium bromide)-2-acryloxypropane monomer, and the SBMA amphiphilic monomer is dimethylpropylsulfonamide ethyl methacrylate monomer; the step 3 is to immerse the substrate surface in an aqueous solution containing 1,3-bis(N,N,N-dimethyloctylammonium bromide)-2-acryloxypropane monomer and dimethylpropylsulfonamide ethyl methacrylate monomer, and adopt a surface-initiated atom transfer radical polymerization method to graft the Geminized amphiphilic polymer monomer and the SBMA amphiphilic monomer onto the hydrogel coating. The above technical scheme introduces Geminized cationic amphiphilic polymer materials with ultra-high charge density into the surface of the "double network" hydrogel material, and utilizes the ultra-high charge density of Geminized amphiphilic molecules in the hydrogel coating to obtain efficient bactericidal activity. At the same time, the high hydrophilicity of polyacrylamide molecules is utilized to give the material surface self-cleaning and biocompatibility properties, thereby constructing a "pore brush" composite coating material that integrates multiple properties such as hydrophilic lubrication, antibacterial and anti-adhesion, which can realize the organic combination of multiple functions on the surface of artificial joints.

[0015] Preferably, an active initiator and an inert initiator are introduced into the aqueous solution in step 3, and the concentration ratio of the active initiator and the inert initiator is controlled by adjusting the input ratio of the Geminized amphiphilic polymer monomer and the SBMA amphiphilic monomer, thereby regulating the grafting density of the polymer brush. By regulating the grafting density, the antibacterial effect of the surface can be regulated.

[0016] Preferably, the ratio of the Geminized amphiphilic polymer monomer to the SBMA amphiphilic monomer is 7:3.

[0017] Preferably, the ratio of the inert initiator to the active initiator is 3:7.

[0018] Preferably, the hydrophilic initiator in step 2 is any one or more of Irgacure-2959, α-ketoglutaric acid, ammonium persulfate, and potassium persulfate.

[0019] Preferably, in step 2, the wavelength of the ultraviolet light is 365 nm, and the ultraviolet light irradiation time is 30-120 minutes.

[0020] In order to solve one of the above technical problems, the second object of the present invention is to provide a technical solution as follows:

[0021] Provided is an application of a hydrogel antibacterial coating with a porous brush structure in the field of artificial joints. A substrate in the shape of an artificial joint is used, and the artificial joint substrate is subjected to steps 1-3 as described in any one of claims 1-7, and a double network hydrogel coating and a polymer brush coating are sequentially polymerized to the surface of the substrate to prepare an artificial joint with a hydrogel antibacterial coating with a porous brush structure. The beneficial effects of the antibacterial coating are applied to the field of artificial joint technology. Its hydrophilic lubricity and reduced friction can improve the comfort and service life of the artificial joint. Its antibacterial properties can effectively prevent bacterial infection, thereby ensuring the life and health safety of patients and medical staff who come into contact with the artificial joint. The present invention grafts a polymer flexible layer on the surface of the artificial joint material through surface grafting modification technology, which can not only improve the lubrication performance of the artificial joint material, but also play a stress buffering role, thereby improving the ability of the artificial joint material to resist physiological impact loads and effectively improving the service life of the artificial joint.

[0022] Preferably, the artificial joint substrate is made of PDMS material. PDMS material is polydimethylsiloxane. Making PDMS material into artificial joint prosthesis belongs to the prior art, which has been disclosed in the literature PDMS: Experimental study of C / C-PDMS-CA composite material for artificial small joint prosthesis. Yang Yongchao. Tianjin Medical University, 2016. For example, it can be made into a PDMS substrate of any solid shape by liquid phase preparation method.

[0023] The technical solution provided by the present invention has the following beneficial effects:

[0024] The present invention provides a method for preparing a hydrogel antibacterial coating with a hole brush structure and its application in the field of artificial joints, which has the following advantages: 1) The hydrogel antibacterial coating of the present invention adopts a surface initiated polymerization method to construct a polymer brush with multiple functions on the surface of the hydrogel material to prepare a "hole brush" composite coating, which is applied to artificial joints and can improve the hydrophilic lubricity of the surface of the artificial joint material, reduce the friction performance of the material, and provide better comfort in use. Compared with the physical coating method, this covalent bonding method can make the hydrogel coating more firmly bonded to the substrate, not easy to fall off, and prevent environmental pollution; 2) Each structural unit in the molecular structure of the grafted Geminized amphiphilic polymer on the antibacterial coating of the present invention has double cationic groups and alkyl long chains, which can give the surface ultra-high charge density and hydrophobicity, have stronger interaction with bacteria, can quickly kill bacteria, and greatly improve the bactericidal performance. Especially for some common drug-resistant bacteria, its ultra-high charge density can also easily exert bactericidal properties; in addition, the "contact" sterilization method can provide ultra-high antibacterial performance, which is beneficial to reduce bacterial resistance; applied in the field of artificial joints, it can better ensure the safety and hygiene of patients and medical staff; 3) The antibacterial coating of the present invention introduces the Geminized cationic amphiphilic polymer material with ultra-high charge density into the surface of the "double network" hydrogel material, and utilizes the ultra-high charge density of the Geminized amphiphilic molecules in the hydrogel coating to obtain efficient bactericidal activity, while utilizing the high hydrophilicity of the polyacrylamide molecules to give the material surface self-cleaning and biocompatibility, constructing a polymer brush / hydrogel composite coating with a "pore brush" composite structure that integrates multiple properties such as hydrophilic lubrication, antibacterial and anti-adhesion, which can achieve an organic combination of multiple functions on the surface of artificial joints. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the preparation route of the polymer brush / hydrogel composite coating (i.e., the porous brush structure hydrogel antibacterial coating of the present invention) on the surface of the medical PDMS artificial joint substrate in an embodiment of the present invention.

[0026] Figure 2 is a list of contact angles of different functional surfaces in the embodiments of the present invention.

[0027] Figure 3 is the water content of the double network hydrogel coating under freeze-thaw cycle conditions in the embodiment of the present invention.

[0028] Figure 4 It is a morphological change diagram of the double network hydrogel coating and the polymer brush / hydrogel composite coating in the embodiment of the present invention.

[0029] Figure 5It is a graph showing the surface wettability changes of the PDMS substrate, double network hydrogel coating, and polymer brush / hydrogel composite coating in the embodiments of the present invention.

[0030] Figure 6 It is a table of grafting density and bactericidal efficiency of different ratios of inert / active initiating groups in the embodiments of the present invention.

[0031] Figure 7 This is a bacterial morphology diagram of the functional surface when the ratio of inert / active initiating groups is 3:7 in an embodiment of the present invention.

[0032] Figure 8 This is a bactericidal graph of the polymer brush at different input ratios of Gemnized amphiphilic polymer monomer and SBMA amphiphilic monomer when the inert / active initiating group ratio is 3:7 in the embodiment of the present invention.

[0033] Fig. 9 This is a diagram of the bactericidal effect of the polymer brush at different input ratios of Gemnized amphiphilic polymer monomer and SBMA amphiphilic monomer when the inert / active initiating group ratio is 3:7 in the embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. For those skilled in the art, other systems, methods and / or features of the present embodiment will become apparent after reviewing the following detailed description. It is intended that all such additional systems, methods, features and advantages are included in this specification, are included within the scope of the present invention, and are protected by the appended claims. Additional features of the disclosed embodiments are described in detail below, and these features will be apparent from the following detailed description.

[0035] This embodiment describes in detail the preparation method of the hydrogel antibacterial coating with a porous brush structure and its application in the field of artificial joints by preparing an artificial joint with a hydrogel antibacterial coating with a porous brush structure of the present invention.

[0036] like Figure 1 As shown, an artificial joint with a hydrogel antibacterial coating having a hole brush structure in this embodiment specifically includes the following steps:

[0037] Step 1, preparing a "double network" hydrogel coating based on ultraviolet light-induced polymerization, the process is as follows: pre-treating the medical PDMS substrate with a plasma surface treatment machine to make the substrate surface rich in hydroxyl active functional groups.

[0038] Step 2, immersing the base material in a hydrogel monomer aqueous solution containing a hydrophilic initiator (the hydrophilic initiator includes one or more components of Irgacure-2959, α-ketoglutaric acid, ammonium persulfate, and potassium persulfate), wherein the hydrogel monomer aqueous solution is an aqueous solution of acrylamide and vinyl alcohol; using ultraviolet light at a wavelength of 365nm to initiate surface polymerization, to prepare a bionic hydrogel artificial joint with high strength and high performance. The irradiation time is 30-120min, and all experiments are carried out at 25°C. The surface wettability changes of the medical substrate PDMS before and after surface treatment, before and after hydrogel preparation and grafting, and after different irradiation reaction times are shown in the figure. Figure 2 shown.

[0039] Step 3, based on the grafting of bifunctional polymer brushes of Geminized amphiphilic polymer monomers and SBMA amphiphilic monomers on the surface of hydrogel and its pore structure, to prepare a polymer brush / hydrogel composite coating with a "pore brush" structure. The specific process is as follows: the hydrogel-modified substrate material is immersed in an aqueous solution containing 1,3-bis(N,N,N-dimethyloctylammonium bromide)-2-acryloxypropane monomer (AGC8) and dimethylpropylsulfonamide ethyl ester (SBMA) monomer, and the Geminized amphiphilic polymer monomer (AGC8) and the amphiphilic monomer (SBMA) are co-grafted into the double-network hydrogel pore material by surface-initiated atom transfer radical polymerization method. Figure 1 The polymer brush / hydrogel composite coating is the porous brush structure hydrogel antibacterial coating of the present invention.

[0040] like Figure 2 Shown is a list of contact angles of different functional surfaces. By comparing the changes in surface wettability before and after surface treatment of the medical substrate, before and after hydrogel preparation and grafting, and after different irradiation reaction times, it can be seen that when the medical artificial joint substrate is treated with Plasma, the surface is rich in hydroxyl active groups; when the surface is modified with hydrogel coating, the surface wettability is significantly reduced, but its surface wettability gradually decreases with the polymerization time, indicating that its surface wettability is optimal when the polymerization time is 30 minutes.

[0041] like Figure 3 The table shows the change in water content of the double network hydrogel coating under different freeze-thaw cycle conditions, indicating that its water content is within the range of normal articular cartilage. Through repeated freeze-thaw cycle treatment, the number of physical cross-linking points between the molecular chains inside the hydrogel increases, the degree of physical cross-linking between the molecular chains increases, the internal structure becomes compact, and more water can be stored, and the lubrication effect is stronger. Figure 3 In the experiment, the water content did not change much after three freeze-thaw cycles, indicating that the surface lubrication performance of the hydrogel coating was excellent. Figure 4The figure shows the morphological changes of the double network hydrogel coating and the polymer brush / hydrogel composite coating. Figure 4 (a) is the microscopic morphology of the double network hydrogel coating. Figure 4 (b) is the microscopic morphology of the polymer brush / hydrogel composite coating. Figure 4 The morphological changes of the hydrogel coating and the polymer brush / hydrogel composite coating observed using a scanning electron microscope further illustrate that compared with a single double-network hydrogel coating, the polymer brush / hydrogel composite coating is denser and has a smoother surface.

[0042] The grafting density of the polymer brushes was regulated by changing the experimental conditions. The steps are as follows: an inert initiator was introduced, and the active initiating group (3-trimethoxysilane-2-bromo-2-methyl-propionate) and the inert initiating group (methyltrimethoxysilane) were modified on the surface of the SiO2 substrate in a ratio of 1:0, 3:7, 1:1, 7:3, and 0:1, respectively, to increase the grafting density of the polymer brushes. The wettability of the polymer brush / hydrogel composite coating was tested using the contact angle test, such as Figure 5 As shown, the surface wettability of the polymer brush / hydrogel composite coating is much lower than that of the PDMS substrate surface and slightly higher than that of the double network hydrogel coating, but it does not have a significant impact.

[0043] like Figure 6 As shown in the figure, Gram-negative bacteria Escherichia coli was selected as the research object to investigate the antibacterial properties of the functional surface, and the bactericidal efficiency of different surfaces was calculated using a plate experiment; Figure 7 The scanning electron microscope was used to observe the changes in bacterial morphology after the bacteria interacted with the antibacterial surface and to examine the bactericidal performance. When the initiator ratio was adjusted to 3:7, the grafting density of the functional surface was the highest, and it also showed higher surface lubrication performance and better antibacterial performance. The bacteria were obviously broken (such as Figure 7 shown).

[0044] like Figure 8 , Fig. 9 As shown, when the inert / active initiating group ratio is 3:7, the bactericidal efficiency of the coating under different AGC8 / SBMA input ratios shows obvious differences. When the ratio of the two is 1:0, 7:3 and 5:5, the bactericidal efficiency exceeds 98%. Fig. 9 The control sample is a control sample, which is a diagram of the sterilization effect on the surface of the PMDS substrate.

[0045] Research has shown that the surface of articular cartilage presents a porous structure, and the surface of the cartilage is mainly composed of hyaluronic acid, proteoglycans and lubricants attached to the material, extending from the surface to form a brush-like layer.

[0046] At present, the improvement of the mechanical strength of hydrogel bionic cartilage materials is often at the expense of the densification of the network microstructure, which leads to a decrease in surface hydration and poor lubrication performance. The present invention improves the required performance by constructing a polymer brush layer with lubrication, sterilization and other functions on the surface of the hydrogel coating. By grafting a polymer flexible layer on the surface of the artificial joint material through surface grafting modification technology, it can not only improve the lubrication performance of the artificial joint material, but also play a stress buffering role, thereby improving the ability of the artificial joint material to resist physiological impact loads and effectively improving the service life of the artificial joint.

[0047] Based on Geminized amphiphilic molecules, we constructed a "pore brush" material with a dense molecular structure on the surface of the double network hydrogel. The advantages of this structure are: 1) The double network hydrogel can form a polymer network through hydrogen bond interactions, and the molecules can be cross-linked through dense and strong hydrogen bonds. Due to the high density of cross-linking points, this hydrogel exhibits special mechanical properties such as high toughness, high ductility and high hardness; 2) At the same time, ionic bond cross-linking points in the hydrogel network will also be formed. Because the density of electrostatic interactions in the system is high and there are differences in strength, the hydrogel system exhibits high strength, high toughness and rapid self-recovery properties of the double network hydrogel in mechanical properties; 3) The Geminized amphiphilic polymer brush on the surface of the hydrogel can not only increase the surface hydration and reduce the surface lubrication performance, but also remove bacteria and other microorganisms deposited on the surface, effectively improving the sterilization and self-cleaning performance. Description of the structure of Geminized amphiphilic polymer brushes: 1,3-bis(N,N,N-dimethyloctylammonium bromide)-2-acryloyloxypropane (AGC8) is a new type of Geminized amphiphilic polymer antibacterial material. Compared with cationic antibacterial materials with a single component, this "double-headed and double-tailed" cationic amphiphilic polymer material can effectively overcome the structural defects of traditional antibacterial materials, endow the material surface with ultra-high positive charge density, and greatly improve the bactericidal efficiency of the material surface. In addition to interacting with bacteria through super-strong electrostatic attraction, the material's own lipophilic hydrophobic alkyl side chain will also spontaneously insert into the bacterial cell membrane, combine with the liposomes in the cell membrane, disrupt the liposome structure, accelerate the death of bacteria, and greatly improve the antibacterial properties of the material surface. At the same time, hydrophilic zwitterionic or acrylamide components are introduced into the polymer brush, and their high hydrophilicity and water-locking ability are used to give the material surface super-hydrophilic lubrication and self-cleaning properties, so as to achieve its stimulus-responsive capture, killing and release of bacteria.

[0048] The present invention innovatively proposes to introduce Geminized amphiphilic molecules into the surface of hydrogel bionic artificial joint materials through surface initiated polymerization, and construct a polymer brush / hydrogel composite coating with a porous brush structure having multiple functions (i.e., the hydrogel antibacterial coating with a porous brush structure of the present invention), which can improve the hydrophilic lubricity and bactericidal properties of the surface of the artificial joint material and reduce the friction properties of the material. In the molecular structure of the Geminized amphiphilic polymer of the present invention, each structural unit has double cationic groups and alkyl long chains, which can give the surface ultra-high charge density and hydrophobicity, have stronger interaction with bacteria, can quickly kill bacteria, and greatly improve the bactericidal properties.

[0049] The above embodiments should be understood to be only used to illustrate the present invention and not to limit the protection scope of the present invention. After reading the contents of the present invention, technicians can make various changes or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

Claims

1. A method for preparing a hydrogel antibacterial coating having a porous brush structure, characterized in that: The steps include: Step 1, pre-treating the surface of the substrate with a plasma surface treatment machine so that the surface is rich in hydroxyl active functional groups; Step 2, immersing the pretreated substrate obtained in step 1 into a hydrogel monomer aqueous solution containing a hydrophilic initiator; the hydrogel monomer aqueous solution is an aqueous solution of acrylamide and vinyl alcohol; surface polymerization is initiated by ultraviolet light to modify a double network hydrogel coating on the surface of the substrate; Step 3, grafting Geminized amphiphilic polymer monomers and SBMA amphiphilic monomers onto the surface of the hydrogel coating obtained in step 2 to form a polymer brush / hydrogel composite coating.

2. The method for preparing a hydrogel antibacterial coating having a porous brush structure according to claim 1, characterized in that: The Geminized amphiphilic polymer monomer is 1,3-bis(N,N,N-dimethyloctylammonium bromide)-2-acryloxypropane monomer, and the SBMA amphiphilic monomer is dimethylpropylsulfonamide ethyl methacrylate monomer; the step 3 is to immerse the substrate surface in an aqueous solution containing 1,3-bis(N,N,N-dimethyloctylammonium bromide)-2-acryloxypropane monomer and dimethylpropylsulfonamide ethyl methacrylate monomer, and adopt a surface-initiated atom transfer radical polymerization method to graft the Geminized amphiphilic polymer monomer and the SBMA amphiphilic monomer onto the hydrogel coating.

3. The method for preparing a hydrogel antibacterial coating having a porous brush structure according to claim 2, characterized in that: In step 3, active initiators and inert initiators are introduced into the aqueous solution. By adjusting the input ratio of the Geminized amphiphilic polymer monomer and the SBMA amphiphilic monomer, the concentration ratio of the active initiator and the inert initiator is controlled, thereby adjusting the grafting density of the polymer brush.

4. The method for preparing a hydrogel antibacterial coating having a porous brush structure according to claim 3, characterized in that: The ratio of Geminized amphiphilic polymer monomer to SBMA amphiphilic monomer is 7:

3.

5. The method for preparing the hydrogel antibacterial coating with a porous brush structure according to claim 3, characterized in that: The ratio of the inert initiator to the active initiator is 3:

7.

6. The method for preparing a hydrogel antibacterial coating having a porous brush structure according to claim 1, characterized in that: The hydrophilic initiator in step 2 is any one or more of Irgacure-2959, α-ketoglutaric acid, ammonium persulfate, and potassium persulfate.

7. The method for preparing a hydrogel antibacterial coating having a porous brush structure according to claim 1, characterized in that: In step 2, the wavelength of the ultraviolet light is 365 nm, and the ultraviolet light irradiation time is 30-120 minutes.

8. Application of a hydrogel antibacterial coating with a porous brush structure in the field of artificial joints, characterized in that: Using a substrate in the shape of an artificial joint, the artificial joint substrate is subjected to steps 1-3 as described in any one of claims 1-7, and the hydrogel coating and the polymer brush coating are sequentially polymerized onto the surface of the substrate to prepare an artificial joint with a porous brush structure hydrogel antibacterial coating.

9. The use of a hydrogel antibacterial coating with a porous brush structure in the field of artificial joints according to claim 8, characterized in that: The artificial joint substrate is made of PDMS material.

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