Super-lubricating and antibacterial integrated water-based biological lubricant as well as preparation method and application thereof

Abstract

The invention provides a super-lubricating and antibacterial integrated water-based biological lubricant as well as a preparation method and application thereof, and relates to the technical field of biological lubricating materials. Three functional monomers, namely polyethylene glycol methacrylate (PEGMA), 3-methacryloyl dopamine (DMA) and methacryloyloxyethyl trimethyl ammonium chloride (METAC), are efficiently integrated through free radical copolymerization, the DMA provides strong interface anchoring capability, the METAC endows excellent hydrated lubrication and antibacterial properties, and the PEGMA optimizes the rheological behavior of a system and reduces the viscosity. The lubricant provided by the invention can be self-assembled in an aqueous solution to form nanoparticles, has excellent wettability and interface adsorbability, is good in stability, has a friction coefficient as low as 0.006, realizes a macroscopic super-lubrication state, shows an antibacterial rate close to 100% for staphylococcus aureus, and realizes efficient unification of super-lubrication and strong antibacterial properties.

Description

Technical Field

[0001] This invention relates to the field of biolubricating materials technology, and in particular to a super-lubricating and antibacterial integrated water-based biolubricant, its preparation method and application. Background Technology

[0002] With the rapid development of biomedical engineering, more stringent requirements have been placed on the comprehensive performance of biomedical materials. In clinical applications such as medical devices, artificial joints, and interventional catheters, the interaction between materials and biological tissues or body fluids is crucial. Ideal functional materials need to possess both extremely low coefficients of friction to minimize mechanical damage and energy dissipation, and highly effective antibacterial activity to prevent implant-related infections. However, most current traditional materials exhibit a disconnect between lubricity and antibacterial properties, making it difficult to achieve a synergistic balance. This has become a key technological bottleneck restricting their widespread application in high-risk biomedical environments.

[0003] Existing technologies often employ methods such as physical blending, surface coating, or sequential modification to achieve functional composites. Common strategies include loading antibacterial agents (silver nanoparticles, antibiotics, quaternary ammonium salts, etc.) into lubricating matrices (such as polyethylene glycol, phospholipids, and hydrogels), or constructing a hydrophilic lubricating layer on an antibacterial substrate. While these methods can combine dual functions to some extent, they have significant drawbacks: physical mixing easily leads to uneven dispersion, burst release, or migration of functional components, which not only reduces antibacterial durability but also poses potential biotoxicity risks; surface coatings often suffer from weak adhesion and poor stability, peeling off under the erosion of body fluids and mechanical shearing, resulting in rapid functional failure. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a water-based bio-lubricant that integrates super-lubricity and antibacterial properties, its preparation method, and its application. The water-based bio-lubricant prepared by this invention exhibits high stability and achieves a highly efficient balance between super-lubricity (friction coefficient less than 0.01) and strong antibacterial properties.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for preparing a water-based bio-lubricant that integrates super-lubricity and antibacterial properties, comprising the following steps: Polyethylene glycol methacrylate, 3-methacrylamide, methacryloyloxyethyltrimethylammonium chloride, an initiator, and an organic solvent were mixed and subjected to a free radical copolymerization reaction under a protective atmosphere to obtain the super-lubricating and antibacterial integrated water-based bio-lubricant.

[0006] Preferably, the molar ratio of polyethylene glycol methacrylate, 3-methacryloyldopamine and methacryloyloxyethyltrimethylammonium chloride is (1~10):(0.5~5):(1~50).

[0007] Preferably, the initiator comprises azobisisobutyronitrile, and the mass of the initiator is 0.5 to 3% of the total mass of polyethylene glycol methacrylate, 3-methacryloyldopamine and methacryloyloxyethyltrimethylammonium chloride.

[0008] Preferably, the organic solvent includes N,N-dimethylformamide.

[0009] Preferably, the protective atmosphere is nitrogen or argon.

[0010] Preferably, the free radical copolymerization reaction is carried out at a temperature of 60-80°C for 6-24 hours.

[0011] Preferably, after the free radical copolymerization reaction, the resulting reaction solution is further subjected to dialysis and freeze-drying in sequence; the dialysis solution used is water, the dialysis bag used has a molecular weight cutoff of 500-3000, the dialysis time is 72-120 hours, and the dialysis solution is replaced every 6-12 hours.

[0012] This invention provides a super-lubricating and antibacterial integrated water-based bio-lubricant prepared by the preparation method described above.

[0013] This invention provides a lubricant comprising a lubricant and water, wherein the lubricant is the super-lubricating and antibacterial integrated water-based bio-lubricant described in the above technical solution.

[0014] This invention provides the application of the super-lubricating and antibacterial integrated water-based bio-lubricant or the lubricating fluid described in the above technical solutions in the preparation of coatings for medical devices or medical implants.

[0015] This invention provides a method for preparing an integrated superlubricating and antibacterial water-based biolubricant, comprising the following steps: mixing polyethylene glycol methacrylate (PEGMA), 3-methacryloyldopamine (DMA), methacryloyloxyethyltrimethylammonium chloride (METAC), an initiator, and an organic solvent, and carrying out a free radical copolymerization reaction under a protective atmosphere to obtain the integrated superlubricating and antibacterial water-based biolubricant. This invention efficiently integrates three functional monomers—PEGMA, DMA, and METAC—through a free radical copolymerization reaction. DMA provides strong interfacial anchoring ability, METAC imparts excellent hydration lubrication and antibacterial properties, and PEGMA optimizes the system's rheological behavior and reduces viscosity. The lubricant provided by this invention can self-assemble into nanoparticles in aqueous solution, exhibiting excellent wettability and interfacial adsorption, good stability, and a friction coefficient as low as 0.006, achieving a macroscopic super-lubricated state. It also shows a near 100% antibacterial rate against Staphylococcus aureus, achieving a highly efficient balance between super-lubricity and strong antibacterial properties. Furthermore, the lubricant has good biocompatibility and environmental adaptability, and has broad application prospects in biomedical fields such as medical plant bodies (e.g., artificial joints) and medical device coatings. Attached Figure Description

[0016] Figure 1 The image is a cryo-electron microscopy image of the terpolymer P (PEGMA-co-DMA-co-METAC) prepared in Example 1. Figure 2 The Zeta potential statistics of the terpolymer P (PEGMA-co-DMA-co-METAC) prepared in Example 1; Figure 3 A bar chart comparing the average friction coefficients of the lubricant solutions used in Examples 1-3; Figure 4 A bar chart comparing the average friction coefficients of the lubricant solutions used in Examples 4-6; Figure 5 A bar chart comparing the average friction coefficients of the lubricant solutions in Application Examples 2 and 7-10. Figure 6 A comparison graph showing the coefficient of friction curves of the lubricant solutions in Application Examples 2, 6, 11, and 12; Figure 7 Bar graphs showing the coefficients of friction of the lubricant solution in Application Example 2 and the PBS buffer in Application Example 13 under different loads; Figure 8 Bar graphs showing the friction coefficients of the lubricant solution in Application Example 2 and the PBS buffer in Application Example 13 at different frequencies; Figure 9 Images of the anti-Staphylococcus aureus effect of the lubricant solutions used in Examples 2 and 6; Figure 10 The graph shows the changes in the resonant frequency of the QCM chip using the lubricant solutions in Application Examples 2 and 12. Detailed Implementation

[0017] This invention provides a method for preparing a water-based bio-lubricant that integrates super-lubricity and antibacterial properties, comprising the following steps: Polyethylene glycol methacrylate (PEGMA), 3-methacryloyldopamine (DMA), methacryloyloxyethyltrimethylammonium chloride (METAC), an initiator, and an organic solvent were mixed and subjected to a free radical copolymerization reaction under a protective atmosphere to obtain the super-lubricating and antibacterial integrated water-based bio-lubricant.

[0018] Unless otherwise specified, all raw materials involved in this invention are commercially available products well known in the art.

[0019] In this invention, the number average molecular weight of the polyethylene glycol methacrylate is preferably 500-2000; the molar ratio of the polyethylene glycol methacrylate, 3-methacryloyldopamine and methacryloyloxyethyltrimethylammonium chloride is preferably (1-10):(0.5-5):(1-50), and can be 10:1:1, 10:1:5, 10:1:10, 10:1:20 or 10:1:50.

[0020] In this invention, the initiator preferably includes azobisisobutyronitrile (AIBN), and the mass of the initiator is preferably 0.5 to 3% of the total mass of polyethylene glycol methacrylate, 3-methacryloyldopamine and methacryloyloxyethyltrimethylammonium chloride, which can be 1%, 2% or 3%.

[0021] In this invention, the organic solvent is preferably N,N-dimethylformamide (DMF). The amount of organic solvent used is not particularly important, as long as it is sufficient to fully dissolve the raw materials. In this invention, the protective atmosphere is preferably nitrogen or argon, specifically high-purity nitrogen or high-purity argon. Preferably, the polyethylene glycol methacrylate, 3-methacryloyldopamine, methacryloyloxyethyltrimethylammonium chloride, and the initiator are dissolved in the organic solvent, and then the protective atmosphere is introduced for 10-30 minutes.

[0022] In this invention, the temperature of the free radical copolymerization reaction is preferably 60~80℃, which can be 60, 70 or 80℃. The temperature can be achieved by an oil bath. The time of the free radical copolymerization reaction is preferably 6~24h, which can be 6, 12 or 24h.

[0023] Following the free radical copolymerization reaction, the present invention preferably further subjectes the resulting reaction solution to sequential dialysis and freeze-drying to obtain the integrated super-lubricating and antibacterial water-based bio-lubricant. In this invention, the dialysis solution used for dialysis is preferably water, preferably deionized water or ultrapure water. The molecular weight cutoff of the dialysis bag used for dialysis is preferably 500-3000, but can be 1000. The dialysis time is preferably 72-120 hours, but can be 80 hours, and preferably the dialysis solution is changed every 6-12 hours. In this invention, the freeze-drying time is preferably 48-120 hours, but can be 72 hours.

[0024] This invention provides a super-lubricating and antibacterial integrated water-based bio-lubricant prepared by the preparation method described above. In this invention, the super-lubricating and antibacterial integrated water-based bio-lubricant is a terpolymer formed by polyethylene glycol methacrylate, 3-methacryloyldopamine, and methacryloyloxyethyltrimethylammonium chloride, denoted as P(PEGMA-co-DMA-co-METAC).

[0025] Existing technologies employing physical blending, surface coating, or sequential modification to achieve multifunctional composites rely on the physical adsorption or encapsulation of functional components. These methods fail to achieve stable and controllable molecular integration at the chemical level, representing low-level "functional stacking" rather than systematic "molecular design." To address these bottlenecks, this invention, based on molecular engineering principles, proposes a novel chemical integration strategy: through free radical copolymerization, catechol units with strong adhesion (from DMA), quaternary ammonium salt units with both hydration, lubrication, and antibacterial functions (from METAC), and polyethylene glycol segments providing steric stability and rheological regulation (from PEGMA) are covalently integrated into the same polymer backbone to construct a structurally well-defined and synergistically performing terpolymer P(PEGMA-co-DMA-co-METAC). This molecular design not only fundamentally solves the problems of stability and compatibility of functional components, but also achieves a highly efficient unity of superlubricity (friction coefficient can be lower than 0.01, and can maintain superlubricity performance under different load and frequency conditions) and strong antibacterial properties (antibacterial rate against Staphylococcus aureus >99%) through the synergistic effect between functional groups—such as interface anchoring of catechol, hydration and antibacterial properties of quaternary ammonium salt, and entropy repulsion and viscosity regulation of PEG chain. It effectively solves the problems of single function and easy failure of traditional materials, and provides a new path for the design of next-generation integrated biolubricating materials.

[0026] This invention provides a lubricant (i.e., a lubricant solution) comprising a lubricant and water, wherein the lubricant is the super-lubricating and antibacterial integrated water-based bio-lubricant described in the above technical solution.

[0027] In this invention, the concentration of the lubricant in the lubricating fluid is preferably 1~10 mg / mL, and the water can be derived from PBS buffer. In this invention, the lubricant is capable of self-assembling into nanoparticles in an aqueous solution.

[0028] This invention provides the application of the super-lubricating and antibacterial integrated water-based bio-lubricant or the lubricating fluid described in the above technical solutions in the preparation of coatings for medical devices or medical implants. This invention integrates PEGMA, DMA, and METAC via covalent bonds through molecular design. This material exhibits strong adsorption and high stability in physiological environments, rapidly forming a stable adsorption layer (i.e., a lubricating film) at the contact interface, achieving a super-lubricating state. It also demonstrates a near 100% antibacterial rate against common pathogenic bacteria such as Staphylococcus aureus, achieving integrated lubrication and antibacterial functions with significantly improved overall performance. This has significant application value in the biomedical field, including medical implants (such as artificial joints) and medical device coatings.

[0029] To further illustrate the present invention, the following detailed description, in conjunction with examples, of the integrated super-lubricating and antibacterial water-based bio-lubricant, its preparation method, and its application, is provided but should not be construed as limiting the scope of protection of the present invention.

[0030] In the examples, PEGMA is polyethylene glycol methacrylate (number average molecular weight ~950), DMA is 3-methacrylamide dopamine, METAC is methacryloyloxyethyltrimethylammonium chloride, and AIBN is azobisisobutyronitrile.

[0031] Example 1 PEGMA, DMA, and METAC were dissolved in N,N-dimethylformamide at a molar ratio of 10:1:20, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, after freeze-drying for 72 hours, the terpolymer P(PEGMA-co-DMA-co-METAC), a super-lubricating and antibacterial integrated water-based bio-lubricant, denoted as P(PEGMA-co-DMA-co-METAC)10:1:20, was obtained.

[0032] Example 2 (as a comparative example) PEGMA and DMA were dissolved in N,N-dimethylformamide at a 1:1 molar ratio, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the binary copolymer P(PEGMA-co-DMA), denoted as P(PEGMA-co-DMA)1:1.

[0033] Example 3 (as a comparative example) PEGMA and DMA were dissolved in N,N-dimethylformamide at a molar ratio of 5:1, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was introduced to purge oxygen for 30 min. Free radical polymerization was then carried out at 70 °C for 12 h. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 h, with the dialysate changed every 8 h. Finally, the product was freeze-dried for 72 h to obtain the binary copolymer P(PEGMA-co-DMA), denoted as P(PEGMA-co-DMA)5:1.

[0034] Example 4 (as a comparative example) PEGMA and DMA were dissolved in N,N-dimethylformamide at a molar ratio of 10:1, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was then introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the binary copolymer P(PEGMA-co-DMA), denoted as P(PEGMA-co-DMA)10:1.

[0035] Example 5 PEGMA, DMA, and METAC were dissolved in N,N-dimethylformamide at a molar ratio of 10:1:1, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was then introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the terpolymer P(PEGMA-co-DMA-co-METAC), denoted as P(PEGMA-co-DMA-co-METAC)10:1:1.

[0036] Example 6 PEGMA, DMA, and METAC were dissolved in N,N-dimethylformamide at a molar ratio of 10:1:5, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was then introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the terpolymer P(PEGMA-co-DMA-co-METAC), denoted as P(PEGMA-co-DMA-co-METAC)10:1:5.

[0037] Example 7 PEGMA, DMA, and METAC were dissolved in N,N-dimethylformamide at a molar ratio of 10:1:10, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was then introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the terpolymer P(PEGMA-co-DMA-co-METAC), denoted as P(PEGMA-co-DMA-co-METAC)10:1:10.

[0038] Example 8 PEGMA, DMA, and METAC were dissolved in N,N-dimethylformamide at a molar ratio of 10:1:50, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the terpolymer P(PEGMA-co-DMA-co-METAC), denoted as P(PEGMA-co-DMA-co-METAC)10:1:50.

[0039] Example 9 (as a comparative example) DMA and METAC were dissolved in N,N-dimethylformamide at a molar ratio of 1:20, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was then introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the binary copolymer P(DMA-co-METAC), denoted as P(DMA-co-METAC)1:20.

[0040] Example 10 (as a comparative example) PEGMA and METAC were dissolved in N,N-dimethylformamide at a molar ratio of 1:2, along with 1% AIBN initiator (by mass of the total monomers). Argon gas was then introduced to purge oxygen for 30 minutes. Free radical polymerization was then carried out at 70°C for 12 hours. After the reaction, the product was placed in a dialysis bag with a molecular weight cutoff of 1000 and dialyzed in deionized water for 80 hours, with the dialysate changed every 8 hours. Finally, the product was freeze-dried for 72 hours to obtain the binary copolymer P(PEGMA-METAC), denoted as P(PEGMA-co-METAC)1:2.

[0041] Application Examples 1-3 The terpolymer P (PEGMA-co-DMA-co-METAC) prepared in Example 1 was dissolved in PBS buffer with a pH of 7.4 to prepare lubricant solutions with concentrations of 1 mg / mL, 5 mg / mL, and 10 mg / mL, which were respectively referred to as Application Example 1, Application Example 2, and Application Example 3.

[0042] Application Examples 4-12 The copolymers obtained in Examples 2-10 were dissolved in PBS buffer solution with a pH of 7.4 to prepare lubricant solutions with a concentration of 5 mg / mL. The lubricant solution prepared in Example 2 was designated as Application Example 4, the lubricant solution prepared in Example 3 was designated as Application Example 5, the lubricant solution prepared in Example 4 was designated as Application Example 6, the lubricant solution prepared in Example 5 was designated as Application Example 7, the lubricant solution prepared in Example 6 was designated as Application Example 8, the lubricant solution prepared in Example 7 was designated as Application Example 9, the lubricant solution prepared in Example 8 was designated as Application Example 10, the lubricant solution prepared in Example 9 was designated as Application Example 11, and the lubricant solution prepared in Example 10 was designated as Application Example 12.

[0043] Application Example 13 PBS buffer with a pH of 7.4.

[0044] Polymer morphology characterization: The morphology of the samples was observed using cryo-transmission electron microscopy. Figure 1 The image shown is a cryo-electron microscopy image of the terpolymer P (PEGMA-co-DMA-co-METAC) prepared in Example 1. The polymer P (PEGMA-co-DMA-co-METAC) can self-assemble into nanoparticles in aqueous solution, with an average particle size of 20.08 nm. Due to the presence of a large number of positively charged METAC monomers in the polymer, these nanoparticles exhibit specific surface charge properties. Figure 2 As shown ( Figure 2The zeta potential of the terpolymer P (PEGMA-co-DMA-co-METAC) prepared in Example 1 is shown in the statistical diagram, and its zeta potential was measured to be +25.37mV.

[0045] Tribological performance testing: The lubrication performance of the lubricant solutions in Application Examples 1-3 was characterized using a CSM reciprocating friction tester. Friction tests were conducted under the same conditions (temperature 30℃, relative humidity 20%), with a load of 1 N. 0.1 mL of lubricant solution was dropped onto the surface of a Ti6Al4V sheet, and the friction pair consisted of a Ti6Al4V sheet and a PDMS ball. The sliding frequency was 1 Hz, and the reciprocating stroke was 5 mm. The results are as follows: Figure 3 As shown ( Figure 3 (A bar chart comparing the average friction coefficients of the lubricant solutions used in Examples 1-3). Figure 3 It can be seen that as the solution concentration increases from 1 mg / mL to 10 mg / mL, the average friction coefficient decreases from 0.0064 to 0.0032, indicating that the adsorption layer formed at high concentrations is more compact and the hydration layer formed on the surface is more stable.

[0046] Next, under the same conditions described above, the lubrication performance of the lubricant solutions corresponding to cases 4-6 was tested, and the results are as follows: Figure 4 As shown ( Figure 4 (A bar chart comparing the average coefficient of friction of the lubricant solutions used in Examples 4-6). Figure 4 It can be seen that after introducing the DMA monomer, as the ratio of PEGMA to DMA was adjusted from 1:1 to 10:1, the coefficient of friction significantly decreased from 1.07 to 0.86. This is attributed to the effective adsorption of the catechol groups of DMA through various interactions, and the improved lubrication performance due to the interaction between PEGMA and surrounding water molecules. Similarly, tests were conducted on the lubricant solutions of Application Examples 2 and 7-10, introducing the METAC monomer. METAC enhances the density of the adsorption layer through electrostatic interaction and has a very strong hydration capacity, enabling it to form a stable hydration layer on the friction pair surface. Figure 5 A bar chart comparing the average coefficient of friction of the lubricant solutions in Application Examples 2 and 7-10 is shown below. Figure 5 As shown, the coefficient of friction in Application Example 9 decreased to 0.006, and when the METAC ratio was significantly increased to 10:1:50, the coefficient of friction in Application Example 10 further decreased to an ultra-low level of 0.005. Finally, the lubrication performance of Application Examples 2, 6, 11, and 12 was compared, and the results are as follows: Figure 6 As shown ( Figure 6 (A comparison graph showing the coefficient of friction curves of the lubricant solutions in Application Examples 2, 6, 11, and 12). Figure 6As shown, due to the limited lubrication properties of PEGMA monomers, the coefficient of friction in Application Example 6 reached 0.7865. Application Example 12 lacked stable adsorption groups, therefore requiring a longer break-in period to achieve a stable lubrication state. Application Example 11 had a high solution viscosity due to strong intermolecular interactions, requiring continuous frictional shearing to achieve a stable lubrication state.

[0047] The lubrication performance of the lubricant solution in Application Example 2 and the PBS buffer solution in Application Example 13 was characterized using a CSM reciprocating friction tester. Friction tests were conducted under identical conditions (temperature 30°C, relative humidity 20%). 0.1 mL of lubricant solution was added to the surface of bovine cartilage, and friction tests were performed using bovine cartilage-to-cartilage pairs. Friction tests were conducted under variable load and frequency conditions, and the results are as follows: Figure 7 and 8 As shown, Figure 7 The bar graph shows the friction coefficients under different loads at a friction frequency of 1 Hz for the lubricant solution in Application Example 2 and the PBS buffer in Application Example 13. Figure 8 The bar graph shows the friction coefficients at different frequencies when the lubricant solution in Application Example 2 and the PBS buffer in Application Example 13 are subjected to a friction load of 3N. It can be seen that when healthy cartilage is used as the friction pair, the use of the copolymer solution can reduce the friction coefficient from 0.028~0.034 to 0.014~0.023.

[0048] Antibacterial performance test This experiment involved preparing Staphylococcus aureus suspensions (approximately 10% concentration) using LB liquid and solid culture media. 6 The bacterial culture was incubated with the sample at a concentration of 5 mg / mL (CFU / mL), and 5 mg of the sample was sterilized under UV light. The experiment was divided into a control group (no sample added) and a sample group (final concentration 5 mg / mL). The bacterial culture and sample were co-cultured for 6 hours (37℃, 200 rpm), and the antibacterial properties of the sample were evaluated using the plate plating method. The test results are as follows: Figure 9 As shown ( Figure 9 (Images of the anti-Staphylococcus aureus effects of the lubricant solutions in Application Examples 2 and 6) Compared with the blank group, Application Example 6 showed no antibacterial effect; while Application Example 2 showed a strong antibacterial effect against Staphylococcus aureus, with an antibacterial rate close to 100%.

[0049] Adsorption performance test The adsorption kinetics (frequency Δf change) of lubricant solution on the surface of gold sensor chip in Application Example 2 and Application Example 12 were monitored in real time using a quartz microcrystalline balance (QCM) with dissipation monitoring. Figure 10The graph shows the changes in the resonant frequency of the QCM chip using the lubricant solutions from Application Examples 2 and 12. There are significant differences in the adsorption and desorption behaviors of the lubricant solutions from Application Examples 12 and 12 on the gold chip surface. Application Example 12 enhanced adsorption strength and stability, improved desorption resistance, and Δf eventually stabilized at -2.42 Hz. In contrast, the DMA monomer introduced in Application Example 2 contains catechol groups, which can generate stronger interfacial interactions with the gold chip, thus exhibiting the largest adsorption capacity and the strongest desorption resistance. After injection of the Application Example 2 solution, Δf instantly dropped to -9.13 Hz, and only a slight change in Δf was observed after rinsing with water.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a water-based bio-lubricant that integrates super-lubrication and antibacterial properties, characterized in that, Includes the following steps: Polyethylene glycol methacrylate, 3-methacrylamide, methacryloyloxyethyltrimethylammonium chloride, an initiator, and an organic solvent were mixed and subjected to a free radical copolymerization reaction under a protective atmosphere to obtain the super-lubricating and antibacterial integrated water-based bio-lubricant.

2. The preparation method according to claim 1, characterized in that, The molar ratio of polyethylene glycol methacrylate, 3-methacrylamide dopamine and methacryloxyethyltrimethylammonium chloride is (1~10):(0.5~5):(1~50).

3. The preparation method according to claim 1, characterized in that, The initiator comprises azobisisobutyronitrile, and the mass of the initiator is 0.5 to 3% of the total mass of polyethylene glycol methacrylate, 3-methacryloyldopamine, and methacryloyloxyethyltrimethylammonium chloride.

4. The preparation method according to claim 1, characterized in that, The organic solvent includes N,N-dimethylformamide.

5. The preparation method according to claim 1, characterized in that, The protective atmosphere is nitrogen or argon.

6. The preparation method according to any one of claims 1 to 5, characterized in that, The free radical copolymerization reaction is carried out at a temperature of 60-80°C for 6-24 hours.

7. The preparation method according to claim 1, characterized in that, After the free radical copolymerization reaction, the resulting reaction solution is subjected to dialysis and freeze-drying in sequence; the dialysis solution used is water, the molecular weight cutoff of the dialysis bag is 500~3000, the dialysis time is 72~120h, and the dialysis solution is replaced every 6~12h.

8. The integrated super-lubricating and antibacterial water-based bio-lubricant prepared by the preparation method according to any one of claims 1 to 7.

9. A lubricating fluid, characterized in that, It includes a lubricant and water, wherein the lubricant is the super-lubricating and antibacterial integrated water-based bio-lubricant of claim 8.

10. The use of the super-lubricating and antibacterial integrated water-based bio-lubricant of claim 8 or the lubricant of claim 9 in the preparation of coatings for medical devices or medical implants.

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