A kind of anti-caries hydrogel material and its preparation method and application

Abstract

The technical field of the present invention is a medical and dental preparation, and provides an anti-caries hydrogel material and a preparation method and application thereof, wherein the preparation method comprises: pretreating a phosphorus source; preparing a monolayer of MXene; preparing a phosphorus source / MXene heterojunction by a weight ratio of 2:1 to 4:1 with a phosphorus source and MXene; preparing a CAP‑RP / MX heterojunction hydrogel; and adding a glucose oxidase solution and a sucrase solution to the CAP‑RP / MX heterojunction hydrogel, placing the solution, and obtaining a CAP‑RP / MX@GI heterojunction hydrogel material. The anti-caries hydrogel material of the present invention can improve the therapeutic effect of early caries.

Description

Technical Field

[0001] The present invention belongs to the technical field of oral medical materials, and more specifically, relates to an anti-caries hydrogel material and a preparation method and application thereof. Background Art

[0002] Dental caries is a common chronic oral disease caused by acidic substances produced by oral bacteria metabolizing sugars, which causes demineralization of tooth hard tissues. According to statistics from the World Health Organization, about 2.7 billion people suffer from dental caries worldwide. Therefore, the development of efficient early-stage dental caries treatment methods has important clinical significance and social value.

[0003] At present, conventional treatments for early caries mainly include fluoride application, pit and fissure sealants, and minimally invasive fillings. However, these methods have the following limitations: excessive use of fluoride may lead to dental fluorosis; pit and fissure sealants cannot treat early caries that have already occurred; and minimally invasive fillings have problems such as material shedding. Although these traditional methods can control the development of caries to a certain extent, it is still difficult to achieve the dual goals of effective antibacterial and promoting remineralization at the same time. Therefore, it is urgent to develop a new treatment plan that can comprehensively solve these two problems. Summary of the invention

[0004] One of the purposes of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a new hydrogel material for improving the therapeutic effect of early caries.

[0005] One aspect of the present invention provides a method for preparing an anti-caries hydrogel material, the preparation method comprising: pretreating a phosphorus source; preparing a monolayer of MXene; preparing a phosphorus source / MXene heterojunction by mixing the phosphorus source and the MXene in a weight ratio of 2:1 to 4:1; preparing a CAP-RP / MX heterojunction hydrogel, comprising: adding acrylamide, ammonium persulfate and N,N′-methylenebisacrylamide to water to prepare an AM solution; adding chitosan and acetic acid to water, stirring at room temperature to obtain a CS solution; dissolving polydopamine in A PDA solution is prepared in a Tris buffer; the PDA solution is mixed with the CS solution, and after being fully mixed, a mixed solution is obtained; and the mixed solution is mixed with the AM solution at a ratio of 0.8:1 to 1.2:1, and the phosphorus source / Mxene heterojunction is added, and after being fully mixed, the mixture is transferred to a mold to obtain a CAP-RP / MX heterojunction hydrogel; and a glucose oxidase solution and a sucrase solution are added to the CAP-RP / MX heterojunction hydrogel, and the mixture is allowed to stand to obtain a CAP-RP / MX@GI heterojunction hydrogel material.

[0006] In an embodiment, the phosphorus source may be red phosphorus.

[0007] In an embodiment, the pretreatment of the phosphorus source may include: grinding 1 to 3 g of red phosphorus, adding it to ultrapure water, transferring it to an autoclave, treating it at 100 to 300° C., washing it after centrifugation at 5000 to 7000 rpm, resuspending it and centrifuging it for 1 to 5 times; dispersing the precipitate into ultrapure water, ultrasonicating it, centrifuging it at 3000 to 5000 rpm, removing the supernatant, centrifuging it again, and freeze-drying the precipitate.

[0008] In an embodiment, the preparation of a single-layer MXene may include: adding a multilayer clay-like MXene into water, ultrasonicating, centrifuging at 4000-5000 rpm, and freeze-drying the supernatant to obtain a single-layer MXene.

[0009] In an embodiment, preparing the phosphorus source and the Mxene in a weight ratio of 2:1 to 4:1 to obtain a phosphorus source / Mxene heterojunction includes: mixing red phosphorus and the Mxene in a weight ratio of 2:1 to 4:1 in water, ultrasonicating, then stirring, centrifuging, and freeze-drying to obtain a red phosphorus / Mxene heterojunction.

[0010] In an embodiment, the preparation of the CAP-RP / MX heterojunction hydrogel may include: adding acrylamide, ammonium persulfate and N,N′-methylenebisacrylamide to water to prepare an AM solution; adding chitosan and acetic acid to water, stirring at room temperature to obtain a CS solution; the pH value of the Tris buffer is 7.0-9.0; the PDA solution and the CS solution are fully mixed to obtain a mixed solution; the mixed solution and the AM solution are mixed at a ratio of 0.8:1-1.2:1, the phosphorus source / Mxene heterojunction is added, and after fully mixing, the mixture is transferred to a mold and placed in a water bath at 70-90°C to obtain a CAP-RP / MX heterojunction hydrogel.

[0011] In an embodiment, obtaining the CAP-RP / MX@GI heterojunction hydrogel material may include: cutting the CAP-RP / MX heterojunction hydrogel, adding glucose oxidase solution and sucrase solution, and placing in a refrigerator overnight to obtain the CAP-RP / MX@GI heterojunction hydrogel material.

[0012] According to another aspect of the present invention, an anti-caries hydrogel material is provided, which is a CAP-RP / MX@GI heterojunction hydrogel material, and the anti-caries hydrogel material comprises a red phosphorus / Mxene heterojunction, a dual enzyme system and CAP, wherein CAP is a dual network hydrogel, RP is red phosphorus, MX is a Mxene heterojunction, GI is a dual enzyme system, and the dual enzyme system is sucrase and glucose oxidase.

[0013] According to another aspect of the present invention, there is provided an anti-caries hydrogel material prepared by the preparation method as described above or use of the anti-caries hydrogel material as described above in treating early-stage caries.

[0014] In an embodiment, the anti-caries hydrogel material can be attached to the tooth surface; and the tooth is irradiated with near-infrared light, so that the anti-caries hydrogel material forms a biofilm on the tooth surface.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The present invention discloses a hydrogel material for treating early caries, which can quickly kill oral cariogenic bacteria and promote tooth remineralization.

[0017] (2) The present invention can inhibit oral biofilm colonization and prevent dental caries.

[0018] (3) The present invention is easy to operate, has high feasibility and excellent antibacterial effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings illustrate exemplary embodiments of the inventive concept and, together with the description, serve to explain the principles of the inventive concept. The accompanying drawings are included to provide a further understanding of the inventive concept and are incorporated in and constitute a part of this specification.

[0020] Figure 1 The RP / MX heterojunction and CAP-RP / MX@GI hydrogel of Example 1 of the present invention are characterized. Figure 1 (A) is a characterization of the microscopic morphology of the red phosphorus / Mxene heterojunction (RP / MX) of Example 1 of the present invention by scanning electron microscopy; Figure 1 (B) is a characterization of the element distribution of the RP / MX heterojunction prepared in Example 1 of the present invention by scanning electron microscopy; Figure 1 (C) is the X-ray photoelectron spectroscopy (XPS) result of the prepared CAP-RP / MX@GI hydrogel in Example 1 of the present invention.

[0021] Figure 2 This is a photothermal effect diagram of the hydrogel material evaluated in Test Example 1 of the present invention. Figure 2 (A) records the real-time temperature change of the evaluated hydrogel material of Test Example 1 of the present invention under near-infrared light irradiation; Figure 2 (B) shows the real-time temperature change of the evaluated hydrogel material under different near-infrared light irradiation powers in Test Example 1 of the present invention; Figure 2 (C) shows the photothermal stability of the hydrogel material evaluated in Test Example 1 of the present invention.

[0022] Figure 3This is an evaluation diagram of the antibacterial ability of the hydrogel material of Test Example 2 of the present invention. Figure 3 (A) is a schematic diagram of the CFU results of the plate coating after being treated with different hydrogel materials in Test Example 2 of the present invention; Figure 3 (B) is a schematic diagram of the bacterial morphology after being treated with different hydrogels in Test Example 2 of the present invention observed under a scanning electron microscope.

[0023] Figure 4 This is a test diagram of the anti-biofilm performance of the hydrogel material of Test Example 3 of the present invention. Figure 4 (A) is the control group of the blank test. Figure 4 (B) shows the morphology of S. mutans biofilm after treatment with CAP-RM@GI hydrogel material.

[0024] Figure 5 This is a test diagram of the anti-biofilm performance of the hydrogel material of Comparative Example 1 of the present invention. Figure 5 (A) is the control group of the blank test. Figure 5 (B) shows the morphology of S. mutans biofilm after treatment with CAP-RM@G hydrogel material. Figure 5 (C) shows the morphology of S. mutans biofilm after treatment with CAP-RM@I hydrogel material.

[0025] Figure 6 The phosphate release performance and remineralization promoting ability of the hydrogel material of Test Example 4 of the present invention are shown. Figure 6 (A) shows the measurement of the phosphate release capacity of the hydrogel material using a phosphate detection kit. Figure 6 (B) shows the hardness variation of the tooth block surface.

[0026] Figure 7 and Figure 8 A graph showing the cell compatibility of the evaluated hydrogel material of Test Example 5 of the present invention is shown. DETAILED DESCRIPTION

[0027] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0028] After long-term research, the applicant found that photodynamic therapy has attracted widespread attention in the field of oral medicine due to its high efficiency and broad-spectrum antibacterial properties. Near-infrared light has stronger tissue penetration ability and is expected to improve the treatment effect. However, there is still a lack of efficient near-infrared light-responsive materials. Hydrogels are widely used in the biomedical field due to their good biocompatibility and controllable drug release properties. Combining hydrogels with photodynamic therapy is expected to achieve high efficiency antibacterial and promote tooth remineralization.

[0029] Enzymes are widely used in the biomedical field. Their high efficiency and specificity make them an ideal treatment method. The synergistic effect of sucrase and glucose oxidase can effectively inhibit bacterial metabolism and growth and reduce the formation of dental plaque biofilm. This provides a new idea for the development of new oral treatment materials. In addition, phosphate ions play a key role in the remineralization of teeth. As a potential phosphorus source, red phosphorus is expected to promote tooth remineralization by slowly releasing phosphate ions.

[0030] In summary, a new type of anti-caries hydrogel material is proposed, which can quickly exert antibacterial effect under the action of near-infrared light and promote tooth remineralization through enzymatic reaction and phosphate release. It is of great significance to improve the treatment effect of early caries and reduce the pain of patients.

[0031] As mentioned above, the first aspect of the present invention provides an anti-caries hydrogel material, which is a CAP-RP / MX@GI heterojunction hydrogel material. The anti-caries hydrogel material includes a red phosphorus / Mxene heterojunction, a dual enzyme system and a CAP double network hydrogel, wherein CAP is a double network hydrogel, RP is red phosphorus, MX is a Mxene heterojunction, GI is a dual enzyme system, and the dual enzyme system is sucrase and glucose oxidase.

[0032] According to the present invention, a dual enzyme heterojunction hydrogel material for treating early caries is provided, wherein the material comprises a red phosphorus / Mxene heterojunction (RP / MX), a dual enzyme system (sucrase and glucose oxidase) and a CAP double network hydrogel.

[0033] The red phosphorus / Mxene heterojunction exerts a photothermal antibacterial effect under 808-nanometer near-infrared light irradiation, converting light energy into heat energy, and quickly killing oral caries-causing bacteria in a short period of time. Mxene has excellent thermal conductivity and photothermal conversion efficiency, which can enhance the photothermal antibacterial effect. The red phosphorus component slowly releases phosphate ions in the local environment to promote the remineralization of early caries teeth.

[0034] The dual enzyme system consists of sucrase and glucose oxidase, which are dispersed in a hydrogel matrix. Sucrase can degrade sucrose in the oral environment, reduce the sugar source of cariogenic bacteria, play a starvation therapy, and inhibit the growth and metabolism of cariogenic bacteria; glucose oxidase can oxidize glucose into gluconic acid, produce hydrogen peroxide, and further inhibit bacterial growth. This dual enzyme system can work continuously and effectively reduce the colonization and formation of dental plaque biofilm.

[0035] CAP double network hydrogel is made of biocompatible and degradable materials. Its rich network structure can provide a good loading platform for red phosphorus / Mxene heterojunction and dual enzyme system, and has appropriate mechanical strength and adhesion ability, which is easy to attach to the tooth surface.

[0036] As mentioned above, on the one hand, the present invention is to design a dual enzyme heterojunction hydrogel material for treating early caries, which includes a red phosphorus / Mxene heterojunction, a dual enzyme system (sucrase and glucose oxidase) and a CAP double network hydrogel. The hydrogel contains a red phosphorus / Mxene heterojunction, and contains sucrase and glucose oxidase. It can be directly attached to the affected tooth surface, quickly exert an antibacterial effect under near-infrared light irradiation, and promote tooth remineralization, providing an efficient and convenient treatment solution for early caries.

[0037] A second aspect of the present invention provides a method for preparing an anti-caries hydrogel material, the preparation method comprising:

[0038] S1. Pretreat the phosphorus source. S2. Prepare a monolayer of MXene. S3. Prepare a phosphorus source / MXene heterojunction by mixing the phosphorus source and the MXene in a weight ratio of 3:1. S4. Prepare a CAP-RP / MX heterojunction hydrogel, including: adding acrylamide, ammonium persulfate and N,N′-methylenebisacrylamide to water to prepare an AM solution; adding chitosan and acetic acid to water, stirring at room temperature to obtain a CS solution; dissolving polydopamine in a Tris buffer to prepare a PDA solution; mixing the PDA solution with the CS solution, and mixing thoroughly to obtain a mixed solution; mixing the mixed solution with the AM solution in a ratio of 0.8:1 to 1.2:1, adding the phosphorus source / MXene heterojunction, and transferring to a mold after mixing thoroughly to obtain a CAP-RP / MX heterojunction hydrogel. S5. Adding glucose oxidase solution and sucrase solution to the CAP-RP / MX heterojunction hydrogel, placing at 4°C to obtain a CAP-RP / MX@GI heterojunction hydrogel material.

[0039] The anti-caries hydrogel material prepared according to the method of an embodiment of the present invention can be used as a dual-enzyme heterojunction hydrogel material for treating early caries, and the material includes a red phosphorus / Mxene heterojunction (RP / MX), a dual enzyme system (sucrase and glucose oxidase) and a CAP double network hydrogel.

[0040] The working principle of the treatment of early caries in the present invention is: under the irradiation of 808 nanometer near-infrared light, the red phosphorus / MXene heterojunction in the CAP-RP / MX@GI heterojunction hydrogel material exhibits good photothermal and photodynamic properties, and quickly kills oral caries bacteria in a short time. At the same time, the red phosphorus component slowly releases phosphate ions in the local environment to promote the remineralization of early caries teeth. Sucrase can degrade sucrose in the oral environment, reduce the sugar source of caries bacteria, and inhibit the growth and metabolism of caries bacteria; glucose oxidase can oxidize glucose into gluconic acid, produce hydrogen peroxide, further inhibit bacterial growth, and effectively reduce the colonization and formation of dental plaque biofilm.

[0041] In step S1, the phosphorus source is pretreated to obtain a phosphorus source that is easy to load and combined with MXene to form a heterojunction material. Specifically, it may include:

[0042] Grind 1-3g of red phosphorus into fine particles with a particle size range of 20-100μm, add it into 50mL of ultrapure water, transfer it into an autoclave, treat it at 100-300℃ for 12h, centrifuge it at 5000-7000rpm for 15min, wash it, resuspend it and repeat the centrifugation for 1-5 times; disperse the precipitate into 200mL of ultrapure water, ultrasonicate it for 2h, centrifuge it at 3000-5000rpm for 15min, remove the supernatant, centrifuge it again at 9000rpm for 5min, and freeze-dry the precipitate at -20℃.

[0043] Preferably, 1.5-2.5 g of red phosphorus can be ground into fine particles with a particle size range of 20-50 μm, added to 50 mL of ultrapure water, transferred to an autoclave, treated at 150-250° C. for 12 h, centrifuged at 5500-6500 rpm for 15 min, washed, and resuspended and centrifuged 2-3 times; the precipitate is dispersed in 200 mL of ultrapure water, ultrasonicated for 2 h, centrifuged at 3500-4500 rpm for 15 min, the supernatant is removed, and centrifuged again at 9000 rpm for 5 min, and the precipitate is freeze-dried at -20° C.

[0044] Preferably, in the present application, the phosphorus source may be red phosphorus, but the present invention is not limited thereto, and other phosphorus sources such as black phosphorus and phosphates may also be used as substitutes. Although other phosphorus sources may also be considered as substitutes, the application of red phosphorus in biomedicine has unique advantages. For example, black phosphorus has a unique layered structure and electrical properties, which may enhance the conductivity of the material, but has poor stability; while phosphates (such as H3PO4) have good water solubility and stability, but may change the pH value of the hydrogel and affect enzyme activity. However, in comparison, red phosphorus performs better in terms of safety, stability and biocompatibility. It can not only form an effective heterogeneous structure with MXene, but also keep the pH of the hydrogel stable, which is conducive to the maintenance of enzyme activity. In addition, red phosphorus can form a nanostructure after treatment, increase the specific surface area, and thus improve the material performance. These characteristics make red phosphorus an ideal phosphorus source choice for oral treatment applications.

[0045] In step S2, preparing a single-layer MXene may specifically include: adding 1 g of multilayer clay-like MXene to 50 mL of water, ultrasonicating for half an hour, centrifuging at 4000-5000 rpm for 5 minutes, and freeze-drying the supernatant to obtain a single-layer MXene.

[0046] Preferably, 1 g of multilayer clay-like Mxene is added to 50 mL of water, and ultrasonicated for half an hour, and preferably centrifuged at 3300-3700 rpm for 5 min.

[0047] In step S3, red phosphorus and the Mxene are mixed in water at a weight ratio of 2:1 to 4:1, ultrasonicated for 1 hour, then stirred for 12 hours, centrifuged at 6000 rpm for 15 minutes, and freeze-dried to obtain a red phosphorus / Mxene heterojunction.

[0048] The weight ratio of red phosphorus and Mxene is recommended to be adjusted within the range of 2:1 to 4:1. Within this range, the optimization of material performance can be achieved, including improving electron transfer efficiency and photothermal conversion capability, while maintaining structural stability and good biocompatibility. If the ratio is lower than 2:1, the photothermal conversion efficiency may be reduced; higher than 4:1, the potential toxicity risk may increase. Extreme ratios may affect the formation of heterojunctions, resulting in unstable material performance, and may interfere with the activity of the hydrogel structure and the dual enzyme system. Therefore, adjusting the ratio within the recommended range can not only optimize material performance, but also ensure the stability and safety of the product. Preferably, the weight ratio of red phosphorus and Mxene is 2.5:1 to 3.5:1, which is the preferred range with better effects.

[0049] In step S4, preparing the CAP-RP / MX heterojunction hydrogel may specifically include: adding 4g acrylamide, 160mg ammonium persulfate and 8mg N,N′-methylenebisacrylamide to 6mL water to prepare an AM solution; adding 3g chitosan and 1g acetic acid to 100mL water, stirring at room temperature for 2h to obtain a CS solution; the concentration of the polydopamine is 1.5mg / mL, and the pH value of the Tris buffer is 7.0-9.0; the PDA solution and the CS solution are mixed at a ratio of 1:1, and after fully mixing, a mixed solution is obtained; the mixed solution and the AM solution are mixed at a ratio of 0.8:1-1.2:1, and the phosphorus source / Mxene heterojunction is added at 2mg / mL, and after fully mixing, the mixture is transferred to a mold and placed in a water bath at 70-90°C, and the CAP-RP / MX heterojunction hydrogel is obtained after 5min.

[0050] The pH value of the Tris buffer may preferably be 8.0 to 8.5, and the water bath temperature may preferably be 80 to 85°C.

[0051] The mixing ratio of the mixed solution to the AM solution is a key parameter and can be adjusted between 0.8:1 and 1.2:1, with 0.9:1 to 1.1:1 being the preferred range for better results. This ratio has a significant effect on the structure and properties of the hydrogel. Adjusting the ratio within this range can optimize the cross-linking density, mechanical strength, and porosity of the hydrogel, thereby affecting its drug loading capacity, release characteristics, and interaction with the oral environment. The appropriate ratio ensures that the hydrogel has sufficient strength to maintain structural integrity while maintaining appropriate flexibility and biocompatibility. A ratio below 0.8:1 may result in insufficient hydrogel strength, while a ratio above 1.2:1 may make the hydrogel too rigid, affecting its adaptability and comfort in the oral cavity.

[0052] In step S5, obtaining the CAP-RP / MX@GI heterojunction hydrogel material may specifically include:

[0053] The CAP-RP / MX heterojunction hydrogel was cut into a size of 5*5*5 mm to unify the size for subsequent in vitro experiments, and 50 μL of 1 mg / mL glucose oxidase solution and 50 μL of sucrase solution were added, and placed in a 4°C refrigerator overnight to obtain the CAP-RP / MX@GI heterojunction hydrogel material.

[0054] In an exemplary embodiment, the preparation method of the dual-enzyme heterojunction hydrogel material for treating early caries may include:

[0055] Step 1: prepare red phosphorus.

[0056] Grind 2 g of red phosphorus finely, add it to 50 mL of ultrapure water, transfer it to a 100 mL Teflon-lined stainless steel autoclave, treat it at 200°C for 12 h, centrifuge it at 6000 rpm for 15 min, wash it, resuspend it and repeat the centrifugation three times; disperse the precipitate into 200 mL of ultrapure water, ultrasonicate it for 2 h, centrifuge it at 4000 rpm for 15 min, remove the supernatant, centrifuge it again at 9000 rpm for 5 min, and freeze-dry the precipitate at -20°C.

[0057] Step 2: Preparation of single-layer MXene.

[0058] Multilayer clay-like MXene1g was added into 50mL water, ultrasonicated for half an hour, centrifuged at 3500rpm1 for 5min, and the supernatant was freeze-dried to obtain a single-layer MXene material.

[0059] Step 3: Red phosphorus / Mxene heterojunction (RP / MX).

[0060] Red phosphorus and Mxene were mixed in water at a weight ratio of 3:1, ultrasonicated for 1 h, then stirred for 12 h, centrifuged at 6000 rpm for 15 min, and freeze-dried to obtain a red phosphorus / Mxene heterojunction.

[0061] Step 4: Preparation of CAP-RP / MX heterojunction hydrogel.

[0062] 4 g acrylamide (AM), 160 mg ammonium persulfate (APS) and 8 mg N,N'-methylenebisacrylamide (MBA) were added to 6 mL water to prepare AM solution. 3 g chitosan (CS) and 1 g acetic acid were added to 100 mL water and stirred at room temperature for 2 h to obtain CS solution. 1.5 mg / mL polydopamine (PDA) was dissolved in Tris buffer with a pH value of 8.0 to prepare PDA solution. PDA solution was mixed with CS solution in a ratio of 1:1. After thorough mixing, the mixed solution was mixed with AM solution in a ratio of 1:1. RP / MX material was added at 2 mg / mL. After thorough mixing, it was transferred to a 10*10*5 mm mold and placed in an 80°C water bath. CAP-RP / MX heterojunction hydrogel was obtained after 5 min.

[0063] Step 5: Preparation of CAP-RP / MX@GI heterojunction hydrogel.

[0064] The hydrogel was cut into a size of 5*5*5mm, and 50 μL of 1 mg / mL glucose oxidase solution and 50 μL of sucrase solution were added, and placed in a 4°C refrigerator overnight to obtain the finished CAP-RP / MX@GI heterojunction hydrogel material.

[0065] In order to better understand the above exemplary embodiments of the present invention, they are further described below in conjunction with specific examples.

[0066] Example 1

[0067] First, prepare red phosphorus. Grind 2g of red phosphorus to a particle size of 50μm. Add 50mL of ultrapure water and transfer to a 100mL Teflon-lined stainless steel autoclave. Treat at 200℃ for 12h, centrifuge at 6000rpm for 15min, wash, resuspend and centrifuge for 3 times. Disperse the precipitate in 200mL of ultrapure water, sonicate for 2h, centrifuge at 4000rpm for 15min, remove the supernatant, centrifuge at 9000rpm for 5min, and freeze-dry the precipitate at -20℃. Then prepare a single-layer MXene. Add 1g of multilayer clay-like MXene to 50mL of water, sonicate for half an hour, centrifuge at 3500rpm for 5min, and freeze-dry the supernatant to obtain a single-layer MXene material. Then, the red phosphorus / Mxene heterojunction (RP / MX) was synthesized by mixing red phosphorus and Mxene in water at a weight ratio of 3:1, ultrasonicating for 1 h, then stirring for 12 h, centrifuging at 6000 rpm for 15 min, and freeze-drying to obtain the red phosphorus / Mxene heterojunction.

[0068] Scanning electron microscopy was used to observe the surface morphology and element distribution of the red phosphorus / Mxene heterojunction. Figure 1 (A) and (B) correspond.

[0069] Further, 4 g acrylamide (AM), 160 mg ammonium persulfate (APS) and 8 mg N, N′-methylenebisacrylamide (MBA) were added to 6 mL of water to prepare AM solution. 3 g chitosan (CS) and 1 g acetic acid were added to 100 mL of water and stirred at room temperature for 2 h to obtain CS solution. 1.5 mg / mL polydopamine (PDA) was dissolved in Tris buffer at pH = 8.0 to prepare PDA solution. The PDA solution was mixed with the CS solution in a ratio of 1:1. After fully mixing, the mixed solution was mixed with the AM solution in a ratio of 1:1. RP / MX material was added at 2 mg / mL. After fully mixing, it was transferred to a 10*10*5 mm mold and placed in an 80°C water bath. CAP-RP / MX heterojunction hydrogel was obtained after 5 min. The hydrogel was cut into a size of 5*5*5mm, and 50 μL of 1 mg / mL glucose oxidase solution and 50 μL of sucrase solution were added, and placed in a 4°C refrigerator overnight to obtain the finished CAP-RP / MX@GI heterojunction hydrogel material.

[0070] The element distribution of each group of materials was observed using an X-ray photoelectron spectrometer. Figure 1 The results show that the final hydrogel material CAP-RP / MX@GI was successfully prepared.

[0071] Among them, the microstructure of the RP / MX heterojunction was studied by scanning electron microscopy (refer to Figure 1 (A)) and element distribution (ref. Figure 1 The results show that the RP / MX heterojunction material was successfully synthesized. Figure 1 (C) shows the X-ray photoelectron spectroscopy (XPS) results. The results show that the final hydrogel material CAP-RP / MX@GI was successfully prepared.

[0072] Test Example 1

[0073] A thermal infrared camera was used to collect real-time thermal images of different hydrogel materials under 1.5W / cm2 near-infrared light to evaluate their photothermal properties.

[0074] A thermal infrared camera was used to collect real-time thermal images of the CAP-RP / MX@GI hydrogel material under near-infrared light of 0.5 W / cm2, 1.0 W / cm2 and 1.5 W / cm2 to evaluate its photothermal properties.

[0075] Under 1.5W / cm2 near-infrared light illumination, the photothermal stability of the hydrogel material was tested by four heating-cooling cycles, each cycle consisting of 10 minutes of light heating and 15 minutes of natural cooling. Figure 2 Corresponding. The hydrogel material has good photothermal performance and photothermal stability.

[0076] Figure 2 This is a photothermal effect diagram of the hydrogel material in Test Example 1 of the present invention. The photothermal effects of different hydrogel materials were evaluated. Figure 2 (A) records the real-time temperature changes of materials under near-infrared light irradiation, Figure 2 (B) shows the real-time temperature changes under different near-infrared light powers. Figure 2 (C) shows the results of evaluating the photothermal stability of the hydrogel material of Test Example 1 of the present invention.

[0077] Test Example 2

[0078] The plate count method was used to determine the in vitro antibacterial effect of different hydrogel samples on Streptococcus mutans under 808 nm near-infrared light / no light. Each material was placed in a 48-well plate with a bacterial suspension culture (250 ml, 1×105 CFU / mL) containing 1 mg / mL sucrose and received different treatments (808 nm near-infrared light irradiation for 10 minutes; the dark group was cultured in the dark for 10 minutes). 20 μL of the treated bacterial suspension was evenly spread on a BHI agar plate and cultured at 37°C for 48 hours. A digital camera was used to record typical images of the culture plate. Results and Figure 3 (A) corresponds to the hydrogel material with good antibacterial ability.

[0079] The morphology of bacteria after treatment with different materials was studied using a scanning electron microscope. A bacterial suspension containing 1 mg / mL sucrose (250 μL, 1×105 CFU / mL of Streptococcus mutans) was mixed with the sample and placed in a 48-well plate. It was irradiated with near-infrared light (808 nm, 1.5 W / cm2) for 10 minutes. Subsequently, the bacterial suspension was centrifuged to obtain a bacterial precipitate, and the bacteria were fixed with 2.5% (v / v) glutaraldehyde, and then the sample was dehydrated with different concentrations of ethanol. After sample preparation, the morphology of the bacteria was observed using a scanning electron microscope. The results are similar to those of the samples. Figure 3 (B) corresponds to the figure. After being treated with the hydrogel material, the bacterial morphology changes, producing an antibacterial effect.

[0080] Figure 3 A is an evaluation diagram of the antibacterial ability of the hydrogel material of Test Example 2 of the present invention. Detection of the antibacterial ability of the hydrogel material: Figure 3 A shows the CFU results of the plate coating after being treated with different hydrogel materials in Test Example 2 of the present invention; Figure 3 B shows the bacterial morphology after being treated with different hydrogels in Test Example 2 of the present invention observed by scanning electron microscope. The results show that the hydrogel material has an excellent antibacterial effect on Streptococcus mutans under 808 nm near-infrared light irradiation, and the dual enzyme irradiation group has the strongest antibacterial effect.

[0081] Test Example 3

[0082] The mixed bacterial liquid of Streptococcus mutans, Actinomyces viscosus and Streptococcus gordonii was added to a 24-well plate containing tooth blocks, followed by the addition of hydrogel materials and co-treatment with a medium containing 1 mg / mL sucrose for 24 hours. The tooth blocks were taken out after treatment under light conditions for 10 minutes. After fixation and dehydration, the morphology of bacteria in the biofilm on the surface of the tooth blocks was observed by scanning electron microscopy. The results showed that the hydrogel material had good anti-biofilm properties under 808 nm near-infrared light illumination, and the decomposition of sucrose and glucose by the dual enzymes also inhibited the growth of bacteria. The biofilm in the CAP-RP / MX@GI group was more dispersed and sparse.

[0083] Figure 4 This is a test diagram of the anti-biofilm performance of the hydrogel material of Test Example 3 of the present invention. It can be seen that the anti-biofilm performance of the hydrogel material is tested: the biofilm morphology of Streptococcus mutans after treatment with the CAP-RP / MX@GI hydrogel material. The results show that the hydrogel material has good anti-biofilm performance under 808 nm near-infrared light illumination, and the decomposition of sucrose and glucose by the dual enzyme also inhibits the growth of bacteria. The biofilm in the CAP-RP / MX@GI group is more dispersed and sparse. Figure 4 (A) control is the control group of the blank test. Among them, CAP-RP / MX@GI can also be called CAP-RM@GI.

[0084] Comparative Example 1

[0085] The mixed bacterial solution of Streptococcus mutans, Actinomyces viscosus and Streptococcus gordonii was added to a 24-well plate containing a tooth block, and then the hydrogel material was added and co-treated with a medium containing 1 mg / mL sucrose for 24 hours. The tooth block was taken out after being treated under light conditions for 10 minutes. After fixation and dehydration, the morphology of bacteria in the biofilm on the surface of the tooth block was observed by scanning electron microscopy. The results showed that under 808 nm near-infrared light, the anti-biofilm effect of the single enzyme hydrogel material of the CAP-RP / MX@G group and the CAP-RP / MX@I group was not strong, and was significantly lower than that of the dual enzyme group in the CAP-RP / MX@GI hydrogel material.

[0086] Figure 5 This is a graph showing the anti-biofilm performance of the hydrogel material of comparative example 1 of the present invention. It can be seen that the anti-biofilm performance of the hydrogel material is tested: the biofilm morphology of Streptococcus mutans after being treated with different hydrogel materials. The results show that under 808 nm near-infrared light, the CAP-RP / MX@G group (see Figure 5 (B)) and CAP-RP / MX@I group (see Figure 5 (C) The anti-biofilm effect of the single enzyme hydrogel material is not significant. Figure 5 (A) control refers to the control group of the blank test. Among them, CAP-RP / MX@G can also be called CAP-RM@G, and CAP-RP / MX@ I can also be called CAP-RM@I.

[0087] Test Example 4

[0088] Detect the phosphate release ability of the hydrogel. Soak the hydrogel in water and expose it to light or not for 3 hours, and record the phosphate concentration in the solution every half hour. It can be seen that 0.5 hours of illumination can reach 45% of the total phosphate release of 3 hours of illumination, and 1 hour can reach 67%.

[0089] The remineralization performance of the hydrogel was tested. The tooth blocks were immersed in a demineralization solution (50mM acetic acid, 2.2mMCa(NO3)2, 2.2mM KH2PO4, 1.0mM NaN3, pH 4.5) for 3 days, and then immersed in a remineralization solution (20mM HEPES, 0.9mM KH2PO4, 1.5mM CaCl2, 130mM KCl, 1.0mM NaN3, pH 7.0). The demineralization was performed for 1h per day, and the material was added and treated with light or darkness for 0.5h, and the pH cycle was performed for 22.5h remineralization. After 7 days, the tooth blocks were collected, and the hardness changes of the tooth block surface were tested using a Vickers hardness tester equipped with a diamond indenter under a load of 50gf. The results showed that the hydrogel material can continuously release phosphate ions and has good remineralization performance.

[0090] Figure 6 This is a graph showing the phosphate release performance and remineralization promotion ability of the hydrogel material of Test Example 4 of the present invention. It can be seen that the phosphate release ability and remineralization promotion performance are: Figure 6 (A) shows the measurement of the phosphate release capacity of the hydrogel material using a phosphate detection kit. Figure 6 (B) shows the hardness change of the tooth block surface. The results show that the hydrogel material can continuously release phosphate ions and has good remineralization-promoting performance.

[0091] Test Example 5

[0092] The proliferation activity of human oral keratinocytes (HOK) and human gingival epithelial cells (HGE) on different hydrogel samples was evaluated. The hydrogels of different groups were immersed in DMEM culture medium to prepare the extract, and then HOK cells and HGE cells (2×104 / well) were cultured in it. The culture medium was removed on the 1st, 3rd, and 5th days, and 330μL of culture medium and CCK-8 reagent mixed solution were added. After incubation for 1 hour, the absorbance was detected at 450nm. The results showed that the hydrogel material has excellent cell compatibility.

[0093] Figure 7 and Figure 8 The diagram of the cell compatibility of the hydrogel materials evaluated in Test Example 5 is shown. Cell compatibility evaluation: CCK-8 kit was used to detect HOK cells cultured on different hydrogel materials (see Figure 7 ) and the proliferation activity of HGE cells (see Figure 8 ). The results showed that the hydrogel material had excellent cell compatibility. HOK cells refer to human oral keratinocytes, and HGE cells refer to human gingival epithelial cells.

[0094] According to the present invention, the following beneficial effects can be achieved: ① Solving the problem of low antibacterial efficiency and incomplete sterilization in existing dental caries treatment; ② Solving the problem that traditional remineralization methods are ineffective and may cause fluoride poisoning; ③ Providing a new therapeutic material that can simultaneously achieve high-efficiency antibacterial and promote remineralization.

[0095] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing an anti-caries hydrogel material, characterized in that: The preparation method comprises: Pretreating a phosphorus source, wherein the phosphorus source is red phosphorus; Preparation of a single layer of Mxene; The phosphorus source and the Mxene are prepared in a weight ratio of 2:1 to 4:1 to obtain a phosphorus source / Mxene heterojunction; Preparing a CAP-RP / MX heterojunction hydrogel, comprising: adding acrylamide, ammonium persulfate and N,N′-methylenebisacrylamide to water to prepare an AM solution; adding chitosan and acetic acid to water, stirring at room temperature to obtain a CS solution; dissolving polydopamine in a Tris buffer to prepare a PDA solution; mixing the PDA solution with the CS solution, and fully mixing to obtain a mixed solution; mixing the mixed solution with the AM solution at a ratio of 0.8:1 to 1.2:1, adding the phosphorus source / MXene heterojunction, and transferring to a mold after fully mixing to obtain a CAP-RP / MX heterojunction hydrogel; and Glucose oxidase solution and sucrase solution were added to the CAP-RP / MX heterojunction hydrogel and allowed to stand to obtain the CAP-RP / MX@GI heterojunction hydrogel material.

2. The method for preparing anticaries hydrogel material according to claim 1, characterized in that: The pre-treated phosphorus source comprises: Grind 1-3g of red phosphorus into fine powder, add it into ultrapure water, transfer it into an autoclave, treat it at 100-300°C, wash it after centrifugation at 5000-7000rpm, repeat the resuspending and centrifugation for 1-5 times; disperse the precipitate into ultrapure water, ultrasonicate it, centrifuge it at 3000-5000rpm, remove the supernatant, centrifuge it again, and freeze-dry the precipitate.

3. The method for preparing the anti-caries hydrogel material according to claim 2, characterized in that: Grind 1-3 g of red phosphorus into fine particles with a particle size range of 20-100 μm.

4. The method for preparing anticaries hydrogel material according to claim 1, characterized in that: The method for preparing the monolayer Mxene comprises: adding multilayer clay-like Mxene into water, ultrasonicating, centrifuging at 4000-5000 rpm, taking the supernatant and freeze-drying to obtain the monolayer Mxene.

5. The method for preparing the anti-caries hydrogel material according to claim 1, characterized in that: The phosphorus source and the Mxene are prepared in a weight ratio of 2:1 to 4:1 to obtain a phosphorus source / Mxene heterojunction, comprising: The red phosphorus and the Mxene are mixed in water at a weight ratio of 2:1 to 4:1, ultrasonicated, then stirred, centrifuged, and freeze-dried to obtain a red phosphorus / Mxene heterojunction.

6. The method for preparing anticaries hydrogel material according to claim 1, characterized in that: The preparation of CAP-RP / MX heterojunction hydrogel comprises: Add acrylamide, ammonium persulfate and N,N′-methylenebisacrylamide into water to prepare AM solution; Chitosan and acetic acid were added to water and stirred at room temperature to obtain CS solution; The pH value of the Tris buffer is 7.0 to 9.0; After the PDA solution and the CS solution are fully mixed, a mixed solution is obtained; and The mixed solution was mixed with the AM solution at a ratio of 0.8:1 to 1.2:1, and the phosphorus source / Mxene heterojunction was added. After being fully mixed, the mixture was transferred to a mold and placed in a 70-90° C. water bath to obtain a CAP-RP / MX heterojunction hydrogel.

7. The method for preparing anticaries hydrogel material according to claim 1, characterized in that: The CAP-RP / MX@GI heterojunction hydrogel material is obtained by: The CAP-RP / MX heterojunction hydrogel was cut, and a glucose oxidase solution and a sucrase solution were added, and the mixture was placed in a refrigerator overnight to obtain the CAP-RP / MX@GI heterojunction hydrogel material.

8. An anti-caries hydrogel material, characterized in that: The anti-caries hydrogel material is prepared according to the preparation method according to any one of claims 1 to 7, and the anti-caries hydrogel material is a CAP-RP / MX@GI heterojunction hydrogel material, and the anti-caries hydrogel material includes a red phosphorus / Mxene heterojunction, a dual enzyme system and CAP, wherein CAP is a dual network hydrogel, RP is red phosphorus, MX is a Mxene heterojunction, GI is a dual enzyme system, and the dual enzyme system is sucrase and glucose oxidase.

9. Use of the anti-caries hydrogel material prepared by the preparation method according to any one of claims 1 to 7 or the anti-caries hydrogel material according to claim 8 in preparing materials for treating early caries.

10. The use according to claim 9, characterized in that: affixing the anti-caries hydrogel material to the surface of teeth; The teeth are irradiated with near-infrared light, so that the anti-caries hydrogel material forms a biofilm on the tooth surface.

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