An antibacterial dental resin material based on the natural molecule cholic acid

Abstract

The present application relates to the technical field of chemical synthesis, in particular to an antibacterial dental resin material based on natural molecule cholic acid. The present application takes cholic acid as raw material, first sequentially gives cholic acid through esterification reaction and acylation reaction photo-curable chemical groups, and then sequentially gives cholic acid through activation reaction and substitution reaction high antibacterial groups to obtain photo-curable high antibacterial cholic acid derivative monomer. The photo-curable high antibacterial cholic acid derivative monomer can be used for the preparation of dental resin material, realizes the improvement of the biocompatibility and antibacterial performance of the dental resin material, has small cytotoxicity, in addition, can avoid the problems such as antibacterial agent leakage and poor antibacterial effect in traditional dental resin material, and has wide application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chemical synthesis, in particular to an antibacterial dental resin material based on natural molecule cholic acid. BACKGROUND

[0002] Cholic acid (3α, 7α, 12α-trihydroxy-5β-cholanic acid) is white in color, a bile acid produced by the decomposition and metabolism of cholesterol, and widely exists in animals and human bodies. Due to the unique chemical structure, cholic acid has excellent biocompatibility and stability, and the unmodified cholic acid itself has certain antibacterial property. The multiple functional groups of carboxyl and hydroxyl in the cholic acid structure make it have excellent group modification property. At present, there are many studies on cholic acid-based small molecule antibacterial agents. Cholic acid is usually used as the main body, and different molecular modifications are carried out at the hydroxyl and carboxyl positions. The prepared cholic acid derivatives are widely used in the fields of biological medicine, material preparation, antibacterial and the like.

[0003] Traditional dental resin generally does not have antibacterial property, and only fluorine and other ingredients are added to prevent dental caries, which cannot effectively inhibit the growth and reproduction of bacteria, resulting in bacterial colonization and biofilm formation on the surface of the resin. In order to achieve antibacterial effect, antibacterial agents such as chlorhexidine and triclosan are usually added to the traditional dental resin. Even if the antibacterial agents are added, the antibacterial effect has time effect, and the antibacterial property will gradually weaken with time, and the antibacterial effect is difficult to last. In addition, the addition of antibacterial agents will have a negative impact on the mechanical properties of the resin, such as reducing the hardness and wear resistance, affecting the service life of the material.

[0004] Therefore, the present application provides a high antibacterial cholic acid derivative monomer. The polar group in the high antibacterial cholic acid derivative monomer is beneficial to adhesion on the solid matrix, and the high molecular weight after polymerization of the monomer helps to reduce the shrinkage of the material. In addition, the high antibacterial cholic acid derivative monomer also has the advantages of low water absorption, corrosion resistance, good biocompatibility and the like. The cell toxicity of the monomer mixed with cholic acid tetramethyl acrylate derivative is smaller than that of commercial dental monomer BisGMA. The monomer does not affect the cell viability in its entire solubility range, and is an excellent dental resin material. In addition, the antibacterial property of the dental resin in the pit and fissure sealing can be realized by modifying the quaternary ammonium salt monomer. This monomer is expected to make up for the deficiency of the traditional sealing agent in the long-acting anticaries performance. SUMMARY

[0005] The purpose of the present application is to provide an antibacterial dental resin material based on natural molecule cholic acid, so as to solve the problems that the traditional dental resin generally does not have antibacterial property, even if the antibacterial agent is added, the antibacterial effect is difficult to last, and the biocompatibility is poor, and the cell toxicity is large and the like.

[0006] To achieve the above object, the application adopts the following technical scheme: a light-curable high-antibacterial cholic acid derivative monomer, taking cholic acid as raw material, first sequentially imparting light-curable chemical groups to cholic acid through esterification reaction and acylation reaction, and then sequentially imparting high-antibacterial groups to cholic acid through activation reaction and substitution reaction.

[0007] Further, the esterification reaction is an esterification reaction between the carboxyl group in the cholic acid molecule and the hydroxyl group in the polyethylene glycol molecule; and the acylation reaction is an acylation reaction between the terminal hydroxyl group in the esterification reaction product and acryloyl chloride.

[0008] Further, the activation reaction is an acylation activation reaction between the residual hydroxyl group in the acylation reaction product and p-nitrophenyl chloroformate; and the substitution reaction is a substitution reaction between the p-nitrophenyloxy group in the activation reaction product and N,N-dimethylethylenediamine.

[0009] The preparation method of the light-curable high-antibacterial cholic acid derivative monomer comprises the following steps:

[0010] S1, esterification reaction

[0011] The pure cholic acid and the polyethylene glycol are dissolved in anhydrous dichloromethane, a condensing agent and a first catalyst are added, after the reaction is completed, the anhydrous dichloromethane is dried, and the esterification reaction product is obtained;

[0012] S2, acylation reaction

[0013] The esterification reaction product of S1 is dissolved in anhydrous dichloromethane, a second catalyst is added, and then acryloyl chloride is slowly dropped for acylation reaction, after the reaction is completed, the solution is dropped into diethyl ether, white precipitates are separated out, centrifugal separation and drying are performed, and the acylation reaction product is obtained;

[0014] S3, activation reaction

[0015] The acylation reaction product of S2 is dissolved in anhydrous dichloromethane, p-nitrophenyl chloroformate is slowly dropped, after the reaction is completed, the anhydrous dichloromethane is dried, and the activation reaction product is obtained;

[0016] S4, substitution reaction

[0017] The activation reaction product of S3 is dissolved in anhydrous dichloromethane, N,N-dimethylethylenediamine is slowly dropped for substitution reaction, after the reaction is completed, the solution is dropped into diethyl ether, white precipitates are separated out, centrifugal separation and drying are performed, and the substitution reaction product, i.e., the light-curable high-antibacterial cholic acid derivative monomer of the application, is obtained.

[0018] Further, in S1, the number average molecular weight of the polyethylene glycol is 2000; the condensing agent comprises DMTMM, and the first catalyst comprises DMAP; and the reaction temperature is normal temperature.

[0019] Further, in the S2, the second catalyst comprises TEA; the acylation reaction is carried out under N2 atmosphere, and the reaction temperature is 0-4 DEG C.

[0020] Further, the S4 further comprises a purification step, the substitution reaction product is dissolved in water, and is subjected to dialysis and freeze-drying to obtain the photocurable high-antibacterial cholic acid derivative monomer; the dialysis has a molecular cut-off of 2000.

[0021] The photocurable high-antibacterial cholic acid derivative monomer is applied as a raw material for preparing the antibacterial dental resin.

[0022] Further, after the silica is added into the resin monomer mixture, the photocurable high-antibacterial cholic acid derivative monomer, the photoinitiator and the accelerator are added, and then the mixture is uniformly mixed and photocured to form an antibacterial dental resin.

[0023] Further, the resin monomer mixture is a mixture of TEGDMA and tetramethyl acrylate cholic acid derivative monomer; the photoinitiator is camphorquinone; and the accelerator is DMAEMA.

[0024] The present application has the following beneficial effects:

[0025] 1. The high-antibacterial cholic acid derivative monomer takes natural molecule cholic acid as a starting point, has the advantages of non-toxicity and good biocompatibility, and the biological source exists in the gastrointestinal tract of the human body.

[0026] 2. Compared with the traditional dental resin without antibacterial performance, the high-antibacterial cholic acid derivative monomer contains a positive charge bactericidal group, and can effectively kill bacteria.

[0027] 3. The high-antibacterial cholic acid derivative monomer has the characteristics of low toxicity, small dosage and high antibacterial performance, and avoids the problems of antibacterial agent leakage and short antibacterial time caused by adding antibacterial agents in the traditional dental resin. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a synthesis step diagram of the high-antibacterial derivative monomer of the present application.

[0029] Figure 2 is a synthesis step diagram of the high-antibacterial derivative monomer of the present application. 1 HNMR spectrum (solvent is deuterated DMSO). DETAILED DESCRIPTION

[0030] The technical solutions of the present application will be described clearly and completely below by combining the drawings in the embodiments of the present application.

[0031] Cholic acid widely exists in animals and human bodies, has excellent biocompatibility and stability, and multiple functional groups such as carboxyl and hydroxyl in the structure of cholic acid make cholic acid have excellent group modification; the present application takes cholic acid as a starting point, modifies an antibacterial group and a light-induced polymerization site on the hydroxyl site through chemical synthesis, constructs a high-antibacterial cholic acid derivative monomer capable of light-induced polymerization, avoids problems such as leakage of traditional antibacterial agents and poor antibacterial effect, and then polymerizes the monomer with a cholic acid-containing tetramethyl acrylate derivative monomer to form a resin; the resin has obvious advantages in antibacterial effect, cytotoxicity and biocompatibility when applied to dental materials.

[0032] As shown in Figure 1 Cholic acid is used as a raw material, light-curable chemical groups are given to cholic acid through esterification reaction and acylation reaction, and high-antibacterial groups are given to cholic acid through activation reaction and substitution reaction, and the specific steps are as follows:

[0033] 1. Esterification reaction

[0034] Pure cholic acid and polyethylene glycol are dissolved in anhydrous dichloromethane, stirred to fully dissolve, then DMTMM and DMAP are added as condensing agents and catalysts, fully dissolved, then reacted at room temperature, and after the reaction is completed, the system is milky white; then the solvent dichloromethane is rotary evaporated and dried to obtain a white solid esterification reaction product.

[0035] 2. Acylation reaction

[0036] The esterification reaction product is dissolved in anhydrous dichloromethane, fully dissolved, then TEA is added as a catalyst, propionyl chloride is slowly added dropwise under N2 atmosphere at 0~4 DEG C, and after the reaction is completed, the system is a light yellow solution.

[0037] 2.1. Purification of light-curable cholic acid monomer

[0038] The light yellow solution after acylation reaction is added dropwise into diethyl ether, and white precipitate is precipitated out, which is collected after centrifugation and dried to obtain a white solid acylation reaction product.

[0039] 3. Activation reaction

[0040] The acylation reaction product is dissolved in anhydrous dichloromethane, then p-nitrochloroformate is slowly added dropwise, the system is a light yellow solution after reaction, then the solvent dichloromethane is rotary evaporated and dried to obtain a yellow solid activation reaction product.

[0041] 4. Substitution reaction

[0042] N,N-dimethylethylenediamine is used to substitute p-nitrochloroformate on the hydroxyl group of cholic acid to give cholic acid high-antibacterial performance.

[0043] The activated reaction product was dissolved in anhydrous dichloromethane, the solution was light yellow, then N,N-dimethyl ethylenediamine was slowly added dropwise, the system instantly turned bright yellow, and the reaction was complete.

[0044] 4.1, purification of antibacterial cholic acid derivative monomer

[0045] The bright yellow solution was slowly added dropwise into ether, and white precipitate was precipitated, which was dried by centrifugation to obtain white solid substitution reaction product; the substitution reaction product was dissolved in water, and high-purity photocurable antibacterial cholic acid derivative monomer was obtained by dialysis and freeze-drying.

[0046] 5, preparation of composite resin

[0047] The antibacterial dental resin was prepared according to the widely used proportioning method of dental resin.

[0048] TEGDMA and tetramethyl acrylate cholic acid derivative monomer were mixed as a resin monomer mixture, silica was added to the resin monomer mixture, then antibacterial cholic acid monomer, photoinitiator CQ and accelerator DMAEMA were added, and the mixture was uniformly mixed and photocured.

[0049] Example 1

[0050] Pure cholic acid powder (CA, white powder) 3.2 g, polyethylene glycol (PEG, number average molecular weight 2000) 17.2 g were dissolved in 100 mL anhydrous dichloromethane, stirred to dissolve completely, then 2.2 g 4-(4,6-dimethoxytriazin-2-yl)-4-methylmorpholine hydrochloride (DMTMM), 1 g 4-dimethylaminopyridine (DMAP) were added and dissolved completely, then the reaction was carried out at room temperature for 48 h, and the system was milky white after the reaction was completed; the solvent dichloromethane was rotary evaporated and dried to obtain white solid powder (CA-PEG), and the yield of this step was 92.57%.

[0051] 10 g CA-PEG was dissolved in 50 mL anhydrous dichloromethane, 2.23 mL triethylamine (TEA) was added after complete dissolution, 1.36 mL acryloyl chloride (AC) was slowly added dropwise under N2 atmosphere at 0-4°C, and the reaction was carried out for 12 h; the light yellow solution after the reaction was added dropwise into 500 mL ether, white precipitate was precipitated, the white precipitate was collected by centrifugation, and dried to obtain white solid product (CA-PEG-AC), and the yield of this step was 84.32%.

[0052] 5 g CA-PEG-AC solid was dissolved in 25 mL anhydrous dichloromethane, then 1.62 g p-nitrochloroformate was slowly added dropwise, the reaction was carried out at room temperature for 6 h, then the solvent dichloromethane was rotary evaporated and dried to obtain yellow solid (CA-PEG-AC-NO2), and the yield of this step was 76.36%.

[0053] Take 5 g CA-PEG-AC-NO2 dissolved in 25 mL of anhydrous dichloromethane, then slowly drop 0.2 mL of N, N-dimethyl ethylenediamine, and react at room temperature for 15 min. Then slowly drop the bright yellow solution into 300 mL of ether, and precipitate white solid (CA-PEG-AC-N ＋ ) after centrifugation and drying. Dissolve the white solid in water, and dialyze (molecular weight cut-off 2000), freeze-dry to obtain the photocurable high-antibacterial cholic acid derivative monomer CA-PEG-AC-N ＋ , with a yield of 62.91% after dialysis and freeze-drying.

[0054] As shown in Figure 2 , the purity of each step product is up to 98-99% detected by 1 H NMR spectrum.

[0055] Example 2

[0056] The antibacterial dental resin was prepared according to the widely used proportioning method of dental resin.

[0057] Mix triethylene glycol methacrylate (TEGDMA) and tetramethyl acrylate cholic acid derivative monomer according to the molar ratio of 1:1 as a resin monomer mixture. Add silica to the resin monomer mixture according to the mass ratio of 3:1 to prepare a composite material. Then add antibacterial cholic acid monomer (accounting for 0.1 mol% of the resin monomer mixture), photoinitiator camphorquinone (CQ, accounting for 0.6 wt.% of the resin monomer mixture), and accelerator dimethylaminoethyl methacrylate (DMAEMA, accounting for 1.2 wt.% of the resin monomer mixture), mix uniformly, and then form under the condition of room temperature and 468 nm wavelength ultraviolet light for 30 s.

[0058] The tetramethyl acrylate derivative of cholic acid in this example is a known material, which has been reported in related literature, such as Marc, A, Gauthier, et al. New Dental Composites Containing Multimethacrylate Derivatives of Bile Acids: A Comparative Study with Commercial Monomers [J]. ACS Applied Materials & Interfaces, 2009, 1(4): 824-832. DOI: 10.1021 / am8002395. It has the advantages of low polymerization shrinkage, good biocompatibility, etc.

[0059] The MTT colorimetric method was used to evaluate the cytotoxicity of 3T3 fibroblasts in vitro, and Table 1 is a cytotoxicity report table of the cholic acid derivative monomer dental resin [cholic acid resin (tetramethyl acrylate cholic acid derivative / TEGDMA) + antibacterial cholic acid monomer] of the present example.

[0060] Table 1 Cytotoxicity report table of the cholic acid derivative monomer dental resin of the present example

[0061]

[0062] The coating plate method was used to evaluate the antibacterial performance of Staphylococcus aureus, and the calculation of hemolysis rate (pig red blood cells) was used to evaluate the biocompatibility of cells; Table 2 is an antibacterial performance and biocompatibility characterization table of the cholic acid derivative monomer dental resin of the present example.

[0063] Table 2 Antibacterial performance and biocompatibility characterization table of the cholic acid derivative monomer dental resin of the present example

[0064]

[0065] It can be seen that the biocompatibility and antibacterial rate of the cholic acid derivative monomer dental resin of the present example are obviously better than those of the commercial dental resin (BisGMA / TEGDMA), and the cytotoxicity is small, which has a good application prospect.

[0066] The present application is not limited to the above best mode, and anyone can derive other various forms of products under the inspiration of the present application, but regardless of any changes in shape or structure, any technical solution with the same or similar technical solutions as the present application falls within the protection scope of the present application.

Claims

1. A photocurable high antibacterial cholic acid derivative monomer, characterized in that: Using cholic acid as a raw material, photocurable chemical groups are first imparted to cholic acid through esterification and acylation reactions, and then highly antibacterial groups are imparted to cholic acid through activation and substitution reactions. The esterification reaction is the esterification reaction between the carboxyl group in the cholic acid molecule and the hydroxyl group in the polyethylene glycol molecule; the acylation reaction is the acylation reaction between the terminal hydroxyl group in the esterification product and acryloyl chloride. The activation reaction is an acylation activation reaction between the residual hydroxyl group in the acylation reaction product and phenyl p-nitrochloroformate; the substitution reaction is a substitution reaction between the p-nitrophenoxy group in the activation reaction product and N,N-dimethylethylenediamine.

2. The method for preparing a photocurable high antibacterial cholic acid derivative monomer according to claim 1, characterized in that, Includes the following steps: S1, Esterification reaction Pure cholic acid and polyethylene glycol were dissolved in anhydrous dichloromethane. A condensing agent and a first catalyst were added. After the reaction was completed, the anhydrous dichloromethane was dried to obtain the esterification reaction product. S2, Acylation reaction The S1 esterification product was dissolved in anhydrous dichloromethane, a second catalyst was added, and then acryloyl chloride was slowly added dropwise to carry out the acylation reaction. After the reaction was completed, the solution was added dropwise to diethyl ether, and a white precipitate was precipitated. The precipitate was separated by centrifugation and dried to obtain the acylation product. S3, Activation Reaction The S2 acylation reaction product was dissolved in anhydrous dichloromethane, and p-nitrochloroformate was slowly added dropwise. After the reaction was completed, the anhydrous dichloromethane was dried to obtain the activated reaction product. S4, Substitution reaction The product of the S3 activation reaction was dissolved in anhydrous dichloromethane, and N,N-dimethylethylenediamine was slowly added dropwise to carry out the substitution reaction. After the reaction was completed, the solution was added dropwise to diethyl ether, and a white precipitate was formed. The precipitate was separated by centrifugation and dried to obtain the substitution reaction product.

3. The method for preparing the photocurable high antibacterial cholic acid derivative monomer according to claim 2, characterized in that: In S1, the number average molecular weight of polyethylene glycol is 2000; the condensing agent includes DMTMM, the first catalyst includes DMAP; and the reaction temperature is room temperature.

4. The method for preparing the photocurable high antibacterial cholic acid derivative monomer according to claim 2, characterized in that: In the S2, the second catalyst includes TEA; the acylation reaction is carried out under a N2 atmosphere at a reaction temperature of 0~4℃.

5. The method for preparing a photocurable high antibacterial cholic acid derivative monomer according to claim 2, characterized in that: The S4 step also includes a purification step, in which the substitution reaction product is dissolved in water, dialyzed, and freeze-dried to obtain a photocurable high antibacterial bile acid derivative monomer; the dialysis molecular cutoff is 2000.

6. The use of the photocurable high antibacterial cholic acid derivative monomer as described or prepared according to any one of claims 1-5 as a raw material for the preparation of antibacterial dental resin.

7. The application according to claim 6, characterized in that: After incorporating silica into a resin monomer mixture, add a photocurable high antibacterial cholic acid derivative monomer, a photoinitiator, and an accelerator. Mix thoroughly and then photocur to form an antibacterial dental resin.

8. The application according to claim 6, characterized in that: The resin monomer mixture is a mixture of TEGDMA and tetramethacrylic acid derivative monomers; the photoinitiator is camphorquinone; and the accelerator is DMAEMA.

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