Dental resin surface antibacterial self-repairing hydrogel coating material and preparation method thereof

Abstract

The invention belongs to the technical field of dental resin materials, and discloses a dental resin surface antibacterial self-repairing hydrogel coating material and a preparation method thereof. The method comprises the following steps: 1) soaking dental resin in a benzophenone solution, and drying to obtain resin treated by benzophenone; 2) dissolving a monomer SBMA, a monomer UPyMA, zinc oxide nanoparticles, N, N '-methylene bisacrylamide and a photoinitiator in a mixed solvent of DMF and water to obtain a hydrogel pre-polymerization solution; and 3) coating the resin surface treated by benzophenone with the hydrogel pre-polymerization liquid, and carrying out ultraviolet irradiation polymerization to obtain the dental resin surface antibacterial self-repairing hydrogel coating. The coating disclosed by the invention has good antibacterial adhesion performance on various bacteria; and meanwhile, the coating has excellent self-repairing performance and relatively good sterilizing performance.

Description

Technical Field

[0001] The invention belongs to the field of dental resin materials, and in particular relates to an antibacterial self-repairing hydrogel coating material on the surface of dental resin and a preparation method thereof. Background Art

[0002] Resin materials are indispensable materials in oral clinical restoration due to their good biocompatibility, stability and wear resistance. However, due to the lack of antibacterial properties of traditional resin materials, bacterial adhesion and biofilm formation lead to restoration failure.

[0003] At present, the commonly used antibacterial modification schemes for dental resin materials include adding fluorine-containing monomers, adding antibacterial agents, adding antibacterial inorganic fillers, etc. Patent CN113173868A discloses a fluorine-containing (meth) acrylate monomer to replace Bis-GMA as the main resin to reduce surface energy, improve hydrophobicity and thus achieve antibacterial adhesion. However, the replacement of Bis-GMA with a fluorine-containing (meth) acrylate monomer may lead to a decrease in the mechanical properties of the resin. Patent CN104887535B achieves antibacterial effects by adding phosphoryl acrylate monomers and silver source compounds. Patent CN111110572B imparts antibacterial properties to resin materials by adding zinc-doped mesoporous silica spheres as inorganic fillers. However, the release of antibacterial components may affect the long-term stability of the mechanical properties of the resin material. Surface modification of the resin to give it antibacterial properties is a better solution to extend the service life of the resin without losing the mechanical properties of the resin itself. Summary of the invention

[0004] In order to overcome the shortcomings and deficiencies of the prior art, the purpose of the present invention is to provide a dental resin surface antibacterial self-repairing hydrogel coating material and a preparation method thereof. The coating of the present invention has good antibacterial adhesion performance, antibacterial property, self-repairing property against a variety of bacteria, and the preparation process is simple.

[0005] The purpose of the present invention is achieved through the following solutions:

[0006] A method for preparing an antibacterial self-repairing hydrogel coating material on a dental resin surface comprises the following steps:

[0007] 1) Soaking a dental resin in a benzophenone solution and then drying to obtain a benzophenone-treated resin; the dental resin is a Bis-GMA / TEGDMA resin; the soaking time is 10 to 20 minutes; the benzophenone solution is an ethanol solution of benzophenone, and the mass ratio of ethanol to benzophenone is 16 to 20:1;

[0008] 2) dissolving monomer [2-(methacryloyloxy)ethyldimethyl-(3-sulfonatepropyl)ammonium hydroxide (SBMA), monomer 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidin-2)ureido)ethyl methacrylate (UPyMA), zinc oxide nanoparticles, crosslinking agent N,N'-methylenebisacrylamide and photoinitiator in a mixed solvent of N,N-dimethylformamide and water to obtain a hydrogel prepolymer solution;

[0009] The mass ratio of the 2-(methacryloyloxy)ethyldimethyl-(3-sulfonic acid propyl)ammonium hydroxide to 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidin-2)ureido)ethyl methacrylate is (5-15):1; the mass ratio of 2-(methacryloyloxy)ethyldimethyl-(3-sulfonic acid propyl)ammonium hydroxide to N,N'-methylenebisacrylamide is 100:(0.05-0.2); the mass ratio of the zinc oxide nanoparticles to 2-(methacryloyloxy)ethyldimethyl-(3-sulfonic acid propyl)ammonium hydroxide is (0.5-5):30; the amount of the photoinitiator is 0.5-1.5% of the mass of the hydrogel prepolymer solution; the volume ratio of N,N-dimethylformamide DMF to water in the mixed solvent is 3:(1-3);

[0010] 3) coating the hydrogel prepolymer solution on the resin surface treated with benzophenone, polymerizing the solution under ultraviolet light, and obtaining an antibacterial self-repairing hydrogel coating on the surface of the dental resin.

[0011] The polymerization time is 2 to 5 minutes; the ultraviolet light has a wavelength of 365 nanometers; the coating amount of the prepolymer solution is 5 to 10 μL / cm 2 .

[0012] The photoinitiator is 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone.

[0013] Compared with the prior art, the present invention has the following beneficial effects and advantages: the coating of the present invention has good antibacterial adhesion performance to a variety of bacteria, the anti-adhesion rate to the Gram-positive bacteria Staphylococcus aureus is 98.9%, the anti-adhesion rate to the Gram-negative bacteria Escherichia coli is 98.6%, and the anti-adhesion rate to the oral caries-causing bacteria Streptococcus mutans is 99.3%; at the same time, the hydrogel has excellent self-repairing performance and good bactericidal performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The SEM images of the coatings prepared in Example 1 and Comparative Examples 1 to 4;

[0015] Figure 2 The cell adhesion status of each group of samples (Example 1, Comparative Examples 1 to 4) after co-culturing L929 cells with each group of samples for 24 hours;

[0016] Figure 3 The results are as follows: The results are as follows: The results are as follows: The results are as follows: The results are as follows: The results are as follows: The results are as follows: The results are as follows: The results are as follows: The results are as follows:

[0017] Figure 4 Live / dead staining images of L929 cells cultured in the extracts of each group of samples (Example 1, Comparative Examples 1-4) for 1, 2, and 3 days;

[0018] Figure 5 The quantitative characterization results of the number of L929 cells cultured in the extracts of each group of samples (Example 1, Comparative Examples 1 to 4) for 1, 2, and 3 days;

[0019] Figure 6 This is a test diagram of the repair performance of the hydrogel prepared in Example 2;

[0020] Figure 7 This is a test diagram of the repair performance of the hydrogel prepared in Comparative Example 6;

[0021] Figure 8 This is a test diagram of the repair performance of the hydrogel prepared in Comparative Example 7;

[0022] Fig. 9 This is a test diagram of the repair performance of the hydrogel prepared in Comparative Example 8. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below in conjunction with specific examples, but the embodiments of the present invention are not limited thereto.

[0024] Embodiment 1:

[0025] A method for preparing an antibacterial self-repairing hydrogel coating material on a dental resin surface comprises the following steps:

[0026] (1) soaking the resin sample in a benzophenone ethanol solution (the mass ratio of ethanol to benzophenone is 20:1) for 15 minutes, taking it out, and drying it at room temperature away from light to obtain a benzophenone-treated resin;

[0027] (2) preparing a hydrogel prepolymer solution: 30% by mass of a monomer [2-(methacryloyloxy)ethyldimethyl-(3-sulfonatepropyl)ammonium hydroxide SBMA, 3% by mass of a monomer 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidine-2)ureido)ethyl methacrylate UPyMA, 1% by mass of an antibacterial agent zinc oxide, 0.03% by mass of a crosslinking agent N,N'-methylenebisacrylamide, and 1% by mass of a photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone are dispersed in a mixed solvent of N,N-dimethylformamide DMF and water in a volume ratio of 3:2 to obtain a hydrogel prepolymer solution; wherein the mass fraction refers to the percentage of the mass of the hydrogel prepolymer solution;

[0028] (3) The hydrogel prepolymer solution is coated on the surface of the benzophenone-treated resin and polymerized under ultraviolet light with a wavelength of 365 nanometers for 3 minutes to obtain a hydrogel coating.

[0029] Embodiment 2:

[0030] A method for preparing an antibacterial self-repairing hydrogel material comprises the following steps:

[0031] (1) preparing a hydrogel prepolymer solution: 30% by mass of a monomer [2-(methacryloyloxy)ethyldimethyl-(3-sulfonatepropyl)ammonium hydroxide SBMA, 3% by mass of a monomer 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidine-2)ureido)ethyl methacrylate UPyMA, 1% by mass of an antibacterial agent zinc oxide, 0.03% by mass of a crosslinking agent N,N'-methylenebisacrylamide, and 1% by mass of a photoinitiator 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone are dispersed in a mixed solvent of N,N-dimethylformamide DMF and water in a volume ratio of 3:2 to obtain a hydrogel prepolymer solution;

[0032] (2) The hydrogel prepolymer solution was injected into the mold and polymerized under ultraviolet light with a wavelength of 365 nanometers for 5 minutes to obtain a large block of hydrogel.

[0033] Comparative Example 1:

[0034] The resin samples without coating were used as blank control group.

[0035] Comparative Example 2:

[0036] The difference between this comparative example and Example 1 is that nano zinc oxide particles and monomer UPyMA are not added.

[0037] Comparative Example 3:

[0038] The difference between this comparative example and Example 1 is that no nano zinc oxide particles are added.

[0039] Comparative Example 4:

[0040] This comparative example is different from Example 1 in that no monomer UPyMA is added.

[0041] Comparative Example 5:

[0042] This comparative example is different from Example 2 in that nano zinc oxide particles and monomer UPyMA are not added.

[0043] Comparative Example 6:

[0044] The difference between this comparative example and Example 2 is that no nano zinc oxide particles are added.

[0045] Comparative Example 7:

[0046] This comparative example is different from Example 2 in that no monomer UPyMA is added.

[0047] Performance Testing:

[0048] 1. Scanning electron microscope morphology observation

[0049] The sample was placed in deionized water to reach swelling equilibrium and then frozen in liquid nitrogen. The frozen sample was placed in a freeze dryer for freeze drying. The surface morphology was observed using a low-magnification tungsten filament scanning electron microscope. The test results are shown in Figure 1 shown. Figure 1 The following are SEM images of the coatings prepared in Example 1 and Comparative Examples 1-4.

[0050] from Figure 1 It can be seen that the surface of Comparative Example 1 is smooth and flat, while the surfaces of Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4 have a loose porous structure unique to hydrogels due to the coating of the hydrogel coating.

[0051] 2. Anti-cell Adhesion Test

[0052] Mouse fibroblast L929 cells were used to characterize the anti-cell adhesion properties of the hydrogel coating. The samples were immersed in 0.5 mL of 5*10 4 / mL L929 cell suspension, incubated at 37℃ for 24h. Use CCK-8 kit to quantitatively evaluate the degree of cell adhesion on the sample surface. Wash the sample three times with sterile PBS buffer, wash away the non-adherent cells on the sample surface, move the sample into a 24-well plate, and add 500μL CCK-8 working solution to each well. After incubation in a constant temperature incubator at 37℃ and 5% CO2 for 2h in the dark, aspirate 100μL CCK-8 incubation solution from each well, add it to a 96-well plate and test the absorbance at 450nm to evaluate the degree of cell adhesion on the sample surface.

[0053] Use Calcein-AM / PI live-dead staining kit to stain cells adhered to the sample surface, and use an inverted fluorescence microscope to observe the sample surface to qualitatively evaluate the cell adhesion on the sample surface. Wash the sample three times with sterile PBS buffer, transfer the sample to a 24-well plate, add 400μL live-dead staining solution (0.05% (v / v) Calcein AM and 0.15% (v / v) PI in PBS solution) to each well, incubate in a constant temperature incubator at 37°C and 5% CO2 for 30 minutes in the dark, and use an inverted fluorescence microscope to observe the cell adhesion on the sample surface. The test results are as follows: Figure 2 and 3 shown.

[0054] Figure 2 The surface cell adhesion of Example 1 and Comparative Examples 1 to 4 after L929 cells were co-cultured with each group of samples for 24 hours;

[0055] Figure 3 These are the quantitative characterization results of the number of surface cells in Example 1 and Comparative Examples 1 to 4 after L929 cells were co-cultured with each group of samples for 24 hours.

[0056] from Figure 2 , 3 It can be seen that the hydrogel coatings of Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4 above all have good anti-adhesion effects on cells.

[0057] 3. Cytocompatibility test

[0058] Mouse fibroblast L929 cells were used to characterize the cell compatibility of the hydrogel coating. L929 cells were cultured in a constant temperature incubator at 37°C and 5% CO2 using DMEM complete medium. After sterilization, the sample was immersed in sterile DMEM complete medium for 24 hours to obtain a 5 mg / mL extract. Then, 1 mL of L929 cell suspension was inoculated into each well of a 24-well plate at a seeding density of 1×10 4cells / mL, cultured for one day to allow it to fully adhere to the wall, then replaced the complete culture medium with the extract, and cultured the cells with the extract for 1, 2, and 3 days, and the culture medium was renewed once a day to ensure sufficient nutrients. The cytotoxicity of the sample extract was evaluated using the CCK-8 kit. On the 1st, 2nd, and 3rd days of culture, some non-adherent cells or cell fragments were gently washed away with sterile PBS, and then 500 μL of CCK-8 working solution was added to each well. After incubation in a constant temperature incubator at 37°C and 5% CO2 for 2 hours in the dark, 100 μL of CCK-8 incubation solution was drawn from each well containing cells, added to a 96-well plate, and the absorbance of the incubation solution was measured at 450 nm using a multifunctional microplate reader to evaluate the cell activity of L929. Next, remove excess CCK-8 working solution in the 24-well plate, gently wash with sterile PBS one to three times, then add 400 μL of live-dead stain (0.05% (v / v) Calcein AM and 0.15% (v / v) PI in PBS) to each well, incubate in a constant temperature incubator at 37°C, 5% CO2 for 30 minutes in the dark, gently remove the stain and gently wash with sterile PBS to remove excess dye, then add 100 μL of sterile PBS to the well plate, and use an inverted fluorescence microscope to observe the live / dead status of the cells.

[0059] Figure 4 Live / dead staining images of L929 cells cultured in the sample extracts of Example 1 and Comparative Examples 1 to 4 for 1, 2, and 3 days;

[0060] Figure 5 The results are quantitative characterization of the number of cells of L929 cells cultured in the sample extracts of Example 1 and Comparative Examples 1-4 for 1, 2, and 3 days.

[0061] from Figure 4 , 5 It can be seen that the hydrogel coatings of Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4 all have good cell compatibility with cells.

[0062] 4. Anti-adhesion test of different bacteria

[0063] Staphylococcus aureus

[0064] Immerse the sample in 1*10 6 CFU / mL Staphylococcus aureus liquid, incubate at 37℃ for 24h. After taking out the sample, wash it three times with PBS buffer and then place it in 1mL PBS buffer for ultrasonic treatment for 15min to obtain the target bacterial liquid. Take 100μL of the target bacterial liquid and spread it on LB solid medium and culture it at 37℃ for 12h.

[0065] Escherichia coli

[0066] Immerse the sample in 1*106 CFU / mL Escherichia coli liquid, incubate at 37℃ for 24h. After taking out the sample, wash it three times with PBS buffer and then place it in 1mL PBS buffer for ultrasonic treatment for 15min to obtain the target bacterial liquid. Take 100 microliters of the target bacterial liquid and spread it on LB solid medium and culture it at 37℃ for 12h.

[0067] Streptococcus mutans

[0068] Immerse the sample in 1*10 6 CFU / mL mutans Streptococcus liquid, incubated anaerobically at 37℃ for 24h. After taking out the sample, wash it three times with PBS buffer and then place it in 1mL PBS buffer for ultrasonic treatment for 15min to obtain the target bacterial liquid. Take 100 microliters of the target bacterial liquid and spread it on the brain heart infusion solid culture medium, and incubate it anaerobically at 37℃ for 12h. The test results are shown in Table 1.

[0069] Table 1 Antibacterial adhesion effect of each group of samples

[0070] Anti-Staphylococcus aureus adhesion rate Anti-E. coli adhesion rate Anti-Mutans Streptococcus adhesion rate Example 1 98.9％ 98.6％ 99.3％ Comparative Example 2 98.0％ 97.9％ 96.5％ Comparative Example 3 96.7％ 96.5％ 86.7％ Comparative Example 4 98.8％ 95.6％ 99.1％

[0071] It can be seen from Table 1 that the anti-adhesion self-healing hydrogel coating prepared in the above embodiment has good anti-adhesion effect on Staphylococcus aureus, Escherichia coli and Streptococcus mutans.

[0072] 5. Sterilization test

[0073] After placing the sterilized sample in a 24-well plate, 10 μL of 1*10 6 CFU / mL mutans Streptococcus bacteria were dropped on the sample surface and incubated at 37°C for 2 hours. 990 μL of sterile PBS buffer was added to each well and ultrasonically dispersed for 5 minutes. 100 μL of bacterial solution was applied to brain heart infusion solid culture medium and anaerobically cultured at 37°C for 12 hours. The test results are shown in Table 2.

[0074] Table 2 Bactericidal effect of each group of samples on Streptococcus mutans

[0075] Killing rate of Streptococcus mutans Example 1 99.9％ Comparative Example 2 11,9％ Comparative Example 3 8.1％ Comparative Example 4 99.6％

[0076] As can be seen from Table 2, Example 1 and Comparative Example 4 with the addition of zinc oxide nanoparticles have good killing effects on Streptococcus mutans, while Comparative Examples 2 and 3 without the addition of zinc oxide nanoparticles do not show any killing effects on Streptococcus mutans.

[0077] 6. Self-healing performance test

[0078] By applying alternating amplitude strains (large strain to destroy the gel structure, small strain to observe the healing of the gel) to the sample, the self-healing of the gel in a short period of time is observed. The test conditions of the rheometer are as follows: the angular frequency is fixed at 10rad / s, the alternating amplitude strains are 1% and 1000%, the test temperature is 25℃, and the normal stress is set to 0N. A large strain of 1000% is applied for 60 seconds to destroy the structure of the sample; a small strain of 1% is applied for 60 seconds to restore the gel structure.

[0079] Figure 6 This is a test diagram of the repair performance of the hydrogel prepared in Example 2; Figure 7 This is a test diagram of the repair performance of the hydrogel prepared in Comparative Example 6; Figure 8 This is a test diagram of the repair performance of the hydrogel prepared in Comparative Example 7; Fig. 9 This is a test diagram of the repair performance of the hydrogel prepared in Comparative Example 8.

[0080] from Figure 6 , 7 It can be seen from Figures 8 and 9 that Example 2 and Comparative Example 6 containing UPyMA monomer transform from gel to sol under high strain and rapidly transform from sol to gel under low strain, and the modulus does not change significantly, showing excellent self-healing performance; Comparative Example 5 and Comparative Example 7 not containing UPyMA monomer show a significant decrease in modulus after high strain and do not show self-healing performance.

Claims

1. A method for preparing an antibacterial self-repairing hydrogel coating material on a dental resin surface, characterized in that: The following steps are involved: 1) soaking the dental resin in a benzophenone solution and then drying to obtain a benzophenone-treated resin; 2) dissolving a monomer [2-(methacryloyloxy)ethyldimethyl-(3-sulfonatepropyl)ammonium hydroxide SBMA, a monomer 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidine-2)ureido)ethyl methacrylate UPyMA, zinc oxide nanoparticles, a crosslinking agent N,N'-methylenebisacrylamide and a photoinitiator in a mixed solvent of N,N-dimethylformamide and water to obtain a hydrogel prepolymer solution; The mass ratio of the 2-(methacryloyloxy)ethyldimethyl-(3-sulfonic acid propyl)ammonium hydroxide to 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidine-2)ureido)ethyl methacrylate is (5-15):1; the mass ratio of 2-(methacryloyloxy)ethyldimethyl-(3-sulfonic acid propyl)ammonium hydroxide to N,N'-methylenebisacrylamide is 100:(0.05-0.2); the mass ratio of the zinc oxide nanoparticles to 2-(methacryloyloxy)ethyldimethyl-(3-sulfonic acid propyl)ammonium hydroxide is (0.5-5):30; 3) coating the hydrogel prepolymer solution on the resin surface treated with benzophenone, polymerizing the solution under ultraviolet light, and obtaining an antibacterial self-repairing hydrogel coating on the surface of the dental resin.

2. The method for preparing the antibacterial self-repairing hydrogel coating material on the surface of dental resin according to claim 1, characterized in that: The dosage of the photoinitiator is 0.5-1.5% of the mass of the hydrogel prepolymer solution; the volume ratio of N,N-dimethylformamide DMF to water in the mixed solvent is 3:(1-3).

3. The method for preparing the antibacterial self-repairing hydrogel coating material on the surface of dental resin according to claim 1, characterized in that: The dental resin is Bis-GMA / TEGDMA resin; The soaking time is 10 to 20 minutes; the benzophenone solution is an ethanol solution of benzophenone, and the mass ratio of ethanol to benzophenone is 16 to 20:

1.

4. The method for preparing the antibacterial self-repairing hydrogel coating material on the surface of dental resin according to claim 1, characterized in that: The polymerization time is 2 to 5 minutes; the ultraviolet light has a wavelength of 365 nanometers; the coating amount of the prepolymer solution is 5 to 10 μL / cm 2 .

5. The method for preparing the antibacterial self-repairing hydrogel coating material on the surface of dental resin according to claim 1, characterized in that: The photoinitiator is 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone.

6. An antibacterial self-repairing hydrogel coating material on the surface of dental resin obtained by the preparation method according to any one of claims 1 to 5.

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