Antibacterial bioactive glass composite material for skull defect repair and preparation method thereof

Abstract

The invention discloses an antibacterial bioactive glass composite material for skull defect repair and a preparation method thereof, and relates to the technical field of bioactive glass materials. The antibacterial bioactive glass composite material for skull defect repair is prepared from the following raw materials in parts by weight: 8 to 15 parts of collagen, 45 to 55 parts of bioactive glass, 20 to 30 parts of hydroxyapatite, 5 to 8 parts of a toughening agent, 1 to 2 parts of an antibacterial agent and 150 to 250 parts of deionized water. The antibacterial bioactive glass composite material for skull defect repair prepared by the invention has excellent bending strength and antibacterial property.

Description

Technical Field

[0001] This invention relates to the field of bioactive glass materials technology, specifically to an antibacterial bioactive glass composite material for skull defect repair and its preparation method. Background Technology

[0002] Skull defects are often caused by factors such as traumatic brain injury, surgery for brain tumors or cerebrovascular diseases, removal of infected necrosis, and correction of congenital skull deformities. The skull not only provides physical protection for brain tissue but also plays a crucial role in maintaining intracranial pressure stability and the integrity of the head structure. Therefore, skull defect repair materials must simultaneously meet the requirements of good biocompatibility, osseointegration capacity, structural support capacity, and long-term stability. Currently, commonly used skull repair materials in clinical practice mainly include metallic materials (such as titanium mesh) and polymeric materials (such as polyetheretherketone). While metallic and inert polymeric materials possess high mechanical strength, their insufficient bioactivity makes it difficult to form true biointegration with host bone tissue, often resulting in mechanical interlocking, which carries the risks of long-term foreign body reactions, infection, and long-term loosening. Bioactive glass, due to its ability to release active ions such as silicon, calcium, and phosphorus in the body fluid environment and form a bone-like hydroxyapatite layer on its surface, thereby chemically bonding with bone tissue, is considered a highly promising bone regeneration material. Simultaneously, its ion dissolution and release can stimulate osteoblast differentiation and new bone formation, exhibiting a certain degree of osteoinductive ability. However, purely bioactive glass materials are brittle and lack sufficient crack and impact resistance, making them prone to cracking or pulverization when molded into large implants, thus limiting their application in skull defect repair. Furthermore, skull repair surgery is a type of neurosurgical procedure requiring extremely high aseptic technique; postoperative infection can lead to serious complications and even endanger life. Traditional bone substitutes often lack antibacterial capabilities, requiring postoperative antibiotics to control infection, but maintaining local drug concentrations is difficult and may induce drug-resistant bacterial strains.

[0003] Chinese invention patent CN102294049A discloses a bioactive glass-chitosan composite bone repair material, its preparation method, and its uses. The method involves adding chitosan to a dilute hydrochloric acid solution and stirring until the chitosan is completely dissolved to obtain solution I; adding distilled water to sodium β-glycerophosphate, stirring, and filtering to remove bacteria to obtain solution II; mixing solution II and solution I and stirring for 1-2 hours to obtain solution III; adding bioactive glass to solution III and stirring for 36-48 hours to obtain solution IV; injecting solution IV into a mold and drying it until it becomes a gel, then freezing at -80℃ and drying to obtain the bioactive glass-chitosan composite scaffold material. This invention has a relatively simple preparation process, easily controllable process parameters, good dispersibility and thermal stability of the bioactive glass, and the prepared bioactive glass-chitosan composite bone repair material exhibits good bioactivity and biocompatibility, as well as good mechanical properties; however, its antibacterial properties are still insufficient.

[0004] Therefore, it is of great significance to develop a bioactive glass composite material for the repair of skull defects that combines excellent mechanical properties with antibacterial properties. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide an antibacterial bioactive glass composite material for skull defect repair and its preparation method.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An antibacterial bioactive glass composite material for skull defect repair, comprising the following raw materials in parts by weight: Collagen 8-15 parts, bioactive glass 45-55 parts, hydroxyapatite 20-30 parts, toughening agent 5-8 parts, antibacterial agent 1-2 parts, deionized water 150-250 parts; The toughening agent is prepared by the following method: S1: Glyceryl glycerol triglycidyl ether reacts with 3,5-dicarboxylic acid to generate intermediate A, as shown in the following schematic equation:

[0007] S2: Intermediate A reacts with lauroyl hydrazine to form a toughening agent. The reaction equation is shown below:

[0008] In step S1, the molar ratio of glycerol triglycidyl ether to 3,5-dicarboxybenzoic acid is 1:(3.01-3.03).

[0009] In step S2, the molar ratio of intermediate A to lauroyl hydrazine is 1:(6.02-6.05).

[0010] The antibacterial agent is prepared by the following method: N1: Dioctylmethyl tertiary amine reacts with epichlorohydrin to generate intermediate 1, and the reaction equation is shown below:

[0011] N2: Intermediate 1 reacts with 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid to generate intermediate 2, as shown in the following schematic equation:

[0012] N3: Terephthaloyl diisocyanate reacts with glycine to form intermediate 3, and the reaction equation is shown below:

[0013] N4: Intermediate 2 reacts with intermediate 3 to form an antibacterial agent. The reaction equation is shown below:

[0014] In step N1, the molar ratio of the dioctylmethyl tertiary amine to epichlorohydrin is 1:1.01.

[0015] In step N2, the molar ratio of intermediate 1 to 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid is 1:1.03.

[0016] In step N3, the molar ratio of terephthaloyl diisocyanate to glycine is 1:2.01.

[0017] In step N4, the molar ratio of intermediate 2 to intermediate 3 is 2.05:1.

[0018] A method for preparing an antibacterial bioactive glass composite material for skull defect repair includes the following steps: (1) Weigh out the following by weight: 8-15 parts collagen, 45-55 parts bioactive glass, 20-30 parts hydroxyapatite, 5-8 parts toughening agent, 1-2 parts antibacterial agent, and 150-250 parts deionized water. (2) Deionized water and collagen were stirred and mixed, and bioactive glass, hydroxyapatite, toughening agent and antibacterial agent were added. After high pressure homogenization, freeze drying and sterilization, antibacterial bioactive glass composite material for skull defect repair was obtained.

[0019] Due to the adoption of the above technical solutions, the beneficial effects of the present invention include: The antibacterial bioactive glass composite material for skull defect repair prepared by this invention has excellent flexural strength and antibacterial properties. Attached Figure Description

[0020] Figure 1 The image shows the proton NMR spectrum of intermediate A prepared in step S1 of Example 1.

[0021] Figure 2 The image shows a high-resolution mass spectrum of intermediate A prepared in step S1 of Example 1.

[0022] Figure 3 The image shows the proton NMR spectrum of the toughening agent prepared in step S2 of Example 1.

[0023] Figure 4 The image shows a high-resolution mass spectrum of the toughening agent prepared in step S2 of Example 1.

[0024] Figure 5 The image shows the proton NMR spectrum of intermediate 1 prepared in step N1 of Example 4.

[0025] Figure 6 This is a high-resolution mass spectrum of intermediate 1 prepared in step N1 of Example 4.

[0026] Figure 7 The photon nuclear magnetic resonance (NMR) spectrum of intermediate 2 prepared by step N2 in Example 4 is shown.

[0027] Figure 8 The high-resolution mass spectrum of intermediate 2 prepared by step N2 in Example 4 is shown.

[0028] Figure 9 The photon nuclear magnetic resonance (NMR) spectrum of intermediate 3 prepared in step N3 of Example 4 is shown.

[0029] Figure 10 The high-resolution mass spectrum of intermediate 3 prepared in step N3 of Example 4 is shown.

[0030] Figure 11 The image shows the proton nuclear magnetic resonance spectrum of the antibacterial agent prepared in step N4 of Example 4.

[0031] Figure 12 The image shows a high-resolution mass spectrum of the antibacterial agent prepared in step N4 of Example 4. Detailed Implementation

[0032] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to these embodiments.

[0033] Example 1 Preparation of toughening agent S1: Under nitrogen protection, 350 ml of toluene and 0.301 mol of 3,5-dicarboxybenzoic acid were stirred and mixed. 0.1 mol of glycerol triglycidyl ether was slowly added dropwise over 20 min. After the addition was complete, 0.031 mol of tetraethylammonium bromide and 0.03 mol of triethylamine were added. The mixture was heated to 80 °C and reacted for 4 h. After cooling to room temperature, the mixture was filtered and distilled under reduced pressure at 60 °C for 2 h. 250 ml of cold diethyl ether was added and stirred to precipitate the precipitate. The precipitate was filtered, washed with cold diethyl ether (3 × 50 ml), and dried under vacuum at 60 °C for 8 h to obtain intermediate A. Its 1H NMR spectrum is shown below. Figure 1 As shown, the proton NMR data are as follows: 1 H NMR (400 MHz, Chloroform- dδ 9.92 (s, 6H), 8.09 (td, J = 5.0, 4.5 Hz, 3H), 8.06-8.01 (m, 6H), 4.33-4.15 (m, 6H), 4.03 (s, 1H), 4.02 (d, J = 5.0 Hz, 3H), 3.89 (dd, J = 12.3, 5.0 Hz, 3H), 3.72-3.40 (m, 10H); its high-resolution mass spectrum is shown below. Figure 2 The mass spectrometry data are as follows: HRMS (m / z): 795.2063 [M+H] + ; S2: Mix 500 ml of glacial acetic acid with 0.602 mol of lauroyl hydrazine, and mix 300 ml of isopropanol with 0.1 mol of intermediate A. Combine the two solutions and react at 55 °C for 3 h. Cool to 0 °C and stir for 8 h to precipitate. Filter the precipitate and wash successively with anhydrous ethanol (3 × 50 ml) and water (3 × 50 ml). Dry under vacuum at 50 °C for 12 h to obtain the toughening agent. Its proton NMR spectrum is shown below. Figure 3 As shown, the proton NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 10.84 (s, 6H), 8.07-8.01(m, 6H), 7.96 (d, J = 6.0 Hz, 6H), 7.79 (tt, J = 5.0, 4.0 Hz, 3H), 4.33-4.15(m, 6H), 4.03 (s, 1H), 4.02 (d, J = 5.0 Hz, 3H), 3.89 (dd, J = 12.3, 5.0 Hz, 3H), 3.71-3.41 (m, 10H), 2.53-2.31 (m, 12H), 1.72-1.50 (m, 12H), 1.35-1.25(m, 96H), 0.90 (t, J = 6.2 (Hz, 18H); its high-resolution mass spectrum is as follows: Figure 4 As shown, the mass spectrometry data are as follows: HRMS (m / z): 1973.3734 [M+H] + .

[0034] Example 2 Preparation of toughening agent S1: Under nitrogen protection, 350 ml of toluene and 0.302 mol of 3,5-dicarboxybenzoic acid were stirred and mixed. 0.1 mol of glycerol triglycidyl ether was slowly added dropwise. After the addition was completed in 20 min, 0.031 mol of tetraethylammonium bromide and 0.03 mol of triethylamine were added. The mixture was heated to 85 °C and reacted for 3.5 h. After cooling to room temperature, the mixture was filtered and distilled under reduced pressure at 60 °C for 2 h. 250 ml of cold diethyl ether was added and stirred to precipitate the precipitate. The precipitate was filtered, washed with cold diethyl ether (3 × 50 ml), and dried under vacuum at 60 °C for 8 h to obtain intermediate A. S2: Mix 500 ml of glacial acetic acid with 0.604 mol of lauroyl hydrazine, and mix 300 ml of isopropanol with 0.1 mol of intermediate A. Mix the two solutions and react at 60 °C for 2.5 h. Cool to 0 °C and stir for 8 h to precipitate. Filter and wash successively with anhydrous ethanol (3 × 50 ml) and water (3 × 50 ml). Dry under vacuum at 50 °C for 12 h to obtain the toughening agent.

[0035] Example 3 Preparation of toughening agent S1: Under nitrogen protection, 350 ml of toluene and 0.303 mol of 3,5-dicarboxybenzoic acid were stirred and mixed. 0.1 mol of glycerol triglycidyl ether was slowly added dropwise. After the addition was completed in 20 min, 0.031 mol of tetraethylammonium bromide and 0.03 mol of triethylamine were added. The mixture was heated to 90 °C and reacted for 3 h. After cooling to room temperature, the mixture was filtered and distilled under reduced pressure at 60 °C for 2 h. 250 ml of cold diethyl ether was added and stirred to precipitate the precipitate. The precipitate was filtered, washed with cold diethyl ether (3 × 50 ml), and dried under vacuum at 60 °C for 8 h to obtain intermediate A. S2: Mix 500 ml of glacial acetic acid with 0.605 mol of lauroyl hydrazine, and mix 300 ml of isopropanol with 0.1 mol of intermediate A. Mix the two solutions and react at 65 °C for 2 h. Cool to 0 °C and stir for 8 h to precipitate. Filter and wash successively with anhydrous ethanol (3 × 50 ml) and water (3 × 50 ml). Dry under vacuum at 50 °C for 12 h to obtain the toughening agent.

[0036] Example 4 Preparation of antibacterial agent N1: Under nitrogen protection, 150 ml of DMF (N,N-dimethylformamide), 0.1 mol of dioctylmethyl tertiary amine, 0.101 mol of epichlorohydrin, and 1 mmol of tetrabutylammonium bromide were stirred and mixed, and reacted at 80 °C for 5 h. The temperature was then lowered to 30 °C, and 20 g of 20 wt% sodium hydroxide solution was slowly added dropwise over 20 min. The reaction continued for 6 h. 100 ml of deionized water was added to dilute the reaction solution, and the mixture was extracted with dichloromethane (2 × 150 ml). The organic phases were combined and washed successively with 80 ml of deionized water and 80 ml of saturated brine. The mixture was dried over 20 g of anhydrous magnesium sulfate, filtered, distilled under reduced pressure at 40 °C for 2 h, and dried under vacuum at 50 °C for 12 h to obtain intermediate 1. Its proton NMR spectrum is shown below. Figure 5 As shown, the proton NMR data are as follows: 1 H NMR (400 MHz, DMSO- d 6 δ 3.96 (d, J = 1.2 Hz, 1H), 3.91-3.76 (m, 2H), 3.38 (d, J = 2.7 Hz, 4H), 3.25 (d, J = 5.0 Hz, 1H), 3.19 (s, 3H), 3.13 (d, J = 5.0 Hz, 1H), 1.80-1.66 (m, 4H), 1.42-1.26 (m, 20H), 0.89 (t, J = 6.3 Hz, 6H); its high-resolution mass spectrum is shown below. Figure 6 As shown, the mass spectrometry data are as follows: HRMS (m / z): 312.3265 [M-Cl] + ; Under nitrogen protection, 250 ml of DMF, 0.1 mol of intermediate 1, and 0.103 mol of 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid were stirred and mixed. 0.011 mol of tetraethylammonium bromide and 0.01 mol of triethylamine were added, and the mixture was heated to 85 °C and reacted for 3.5 h. After cooling to room temperature, the mixture was filtered, and the solution was rotary evaporated at 80 °C to constant weight. 150 ml of cold n-hexane was added and stirred to precipitate the precipitate. The precipitate was filtered, washed with cold n-hexane (3 × 50 ml), and dried under vacuum at 60 °C for 12 h to obtain intermediate 2. Its 1H NMR spectrum is shown below. Figure 7 As shown, the proton NMR data are as follows: 1 H NMR (400 MHz, DMSO- d 6δ 11.72 (s, 1H), 7.77 (d, J = 5.0Hz, 1H), 7.28 (d, J = 5.0 Hz, 1H), 5.33 (d, J = 4.9 Hz, 1H), 4.34 (d, J = 4.1Hz, 1H), 4.18 (d, J = 2.0 Hz, 2H), 3.41-3.22 (m, 6H), 3.15 (s, 3H), 2.09 (s, 3H), 1.80-1.66 (m, 4H), 1.43-1.26 (m, 20H), 0.89 (t, J = 6.3 Hz, 6H); its high-resolution mass spectrum is shown below. Figure 8 As shown, the mass spectrometry data are as follows: HRMS (m / z): 465.3691 [M-Cl] + ; N3: Under nitrogen protection, 200 ml of anhydrous DMF and 0.1 mol of terephthaloyl diisocyanate were stirred and mixed thoroughly. 0.201 mol of glycine was added in four equal batches (10 min intervals between batches). The mixture was heated to 40 °C and reacted for 10 h. After cooling to room temperature, the mixture was rotary evaporated at 70 °C to constant weight. The final weight was determined by diluting with 150 ml of a mixed solution of DMF and toluene (V... DMF :V 甲苯 =2:1) ​​recrystallization, filtration, and vacuum drying at 60℃ for 10 h yielded intermediate 3; its proton NMR spectrum is shown below. Figure 9 As shown, the proton NMR data are as follows: 1 H NMR (400 MHz, DMSO- d 6 δ 12.40 (s, 2H), 10.21 (s, 2H), 7.94 (s, 4H), 7.69 (s, 2H), 3.85 (d, J = 1.6Hz, 4H); its high-resolution mass spectrum is shown below. Figure 10 The mass spectrometry data are as follows: HRMS (m / z): 367.0815 [M+H] + ; N4: Under nitrogen protection, 800 ml of acetonitrile and 0.1 mol of intermediate 3 were stirred and mixed. 0.21 mol of dicyclohexylcarbodiimide and 0.02 mol of 4-dimethylaminopyridine were added, and the mixture was stirred for 15 min. Then, 0.205 mol of intermediate 2 was added, and the reaction was carried out at 25 °C for 18 h. After filtration, the mixture was distilled under reduced pressure at 50 °C for 1 h. The final product was obtained using a 400 ml mixture of ethyl acetate and n-hexane (V... 乙酸乙酯 :V 正己烷 =8:2) recrystallized, filtered, and vacuum dried at 60℃ for 12 h to obtain the antibacterial agent; its proton nuclear magnetic resonance spectrum is as follows. Figure 11 As shown, the proton NMR data are as follows:1 HNMR (400 MHz, DMSO- d 6 ) δ 11.72 (s, 2H), 10.21 (s, 2H), 7.94 (s, 4H), 7.76(dd, J = 12.5, 5.0 Hz, 2H), 7.68 (d, J = 2.6 Hz, 2H), 7.28 (d, J = 5.0 Hz, 2H), 5.06 (d, J = 1.1 Hz, 2H), 4.38-4.19 (m, 4H), 3.99-3.82 (m, 4H), 3.46-3.22 (m, 12H), 3.22 (s, 6H), 2.09 (s, 6H), 1.80-1.66 (m, 8H), 1.43-1.26 (m,40H), 0.89 (t, J = 6.3 Hz, 12H); its high-resolution mass spectrum is as follows: Figure 12 The mass spectrometry data are as follows: HRMS (m / z): 630.3992 [M-2Cl] 2+ .

[0037] Example 5: Preparation of antibacterial bioactive glass composite material for skull defect repair (1) Weigh the following by weight: 8g of collagen (recombinant human collagen), 45g of bioactive glass, 20g of hydroxyapatite, 5g of toughening agent (prepared in Example 1), 1g of antibacterial agent (prepared in Example 4), and 150g of deionized water; (2) Mix deionized water with collagen and stir at 500 rpm for 2 hours. Add bioactive glass, hydroxyapatite, antibacterial agent and toughening agent. Place in a high-pressure homogenizer and homogenize 5 times under 20 MPa pressure. Then place in a polytetrafluoroethylene mold (size 100 mm × 50 mm × 10 mm) and freeze dry at -50℃ for 24 hours. Sterilize by irradiation with γ-rays (irradiation dose 25 kGy) for 2 hours to obtain antibacterial bioactive glass composite material for skull defect repair.

[0038] Example 6: Preparation of antibacterial bioactive glass composite material for skull defect repair (1) Weigh the following by weight: 12g of collagen (recombinant human collagen), 50g of bioactive glass, 25g of hydroxyapatite, 6g of toughening agent (prepared in Example 2), 1.5g of antibacterial agent (prepared in Example 4), and 200g of deionized water; (2) Mix deionized water with collagen and stir at 500 rpm for 2 hours. Add bioactive glass, hydroxyapatite, antibacterial agent and toughening agent. Place in a high-pressure homogenizer and homogenize 5 times under 20 MPa pressure. Then place in a polytetrafluoroethylene mold (size 100 mm × 50 mm × 10 mm) and freeze dry at -50℃ for 24 hours. Sterilize by irradiation with γ-rays (irradiation dose 25 kGy) for 2 hours to obtain antibacterial bioactive glass composite material for skull defect repair.

[0039] Example 7: Preparation of antibacterial bioactive glass composite material for skull defect repair (1) Weigh the following by weight: 15g of collagen (recombinant human collagen), 55g of bioactive glass, 30g of hydroxyapatite, 8g of toughening agent (prepared in Example 3), 2g of antibacterial agent (prepared in Example 4), and 250g of deionized water; (2) Mix deionized water with collagen and stir at 500 rpm for 2 hours. Add bioactive glass, hydroxyapatite, antibacterial agent and toughening agent. Place in a high-pressure homogenizer and homogenize 5 times under 20 MPa pressure. Then place in a polytetrafluoroethylene mold (size 100 mm × 50 mm × 10 mm) and freeze dry at -50℃ for 24 hours. Sterilize by irradiation with γ-rays (irradiation dose 25 kGy) for 2 hours to obtain antibacterial bioactive glass composite material for skull defect repair.

[0040] Comparative Example 1 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the toughening agent is replaced with an equal weight of toughening agent prepared by the following method: The preparation method of the toughening agent is basically the same as that in Example 2, except that the glycerol triglycidyl ether in step S1 is replaced with 0.15 mol of ethylene glycol diglycidyl ether; and the amount of lauroyl hydrazine in step S2 is replaced with 0.402 mol.

[0041] Comparative Example 2 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the toughening agent is replaced with an equal weight of toughening agent prepared by the following method: The preparation method of the toughening agent is basically the same as that in Example 2, except that the glycerol triglycidyl ether in step S1 is replaced with 0.075 mol of pentaerythritol glycidyl ether; and the amount of lauroyl hydrazine in step S2 is replaced with 0.804 mol.

[0042] Comparative Example 3 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the toughening agent is replaced with an equal weight of toughening agent prepared by the following method: The preparation method of the toughening agent is basically the same as that in Example 2, except that the 3,5-dicarboxybenzoic acid in step S1 is replaced with an equimolar amount of 3-carboxybenzoic acid; and the amount of lauroyl hydrazine in step S2 is replaced with 0.302 mol.

[0043] Comparative Example 4 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the toughening agent is replaced with an equal weight of toughening agent prepared by the following method: The preparation method of the toughening agent is basically the same as that in Example 2, except that lauroyl hydrazine in step S2 is replaced with an equimolar amount of hexanoyl hydrazine.

[0044] Comparative Example 5 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the toughening agent is replaced with an equal weight of toughening agent prepared by the following method: The preparation method of the toughening agent is basically the same as that in Example 2, except that the amount of lauroyl hydrazine in step S2 is replaced with 0.402 mol.

[0045] Comparative Example 6 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that the dioctylmethyl tertiary amine in step N1 is replaced with an equimolar amount of N,N-dimethyl-n-octylamine.

[0046] Comparative Example 7 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that the 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid in step N2 is replaced with an equimolar amount of 5-methyl-4-oxopiperidine-2-carboxylic acid (CAS No. 54525-50-7).

[0047] Comparative Example 8 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that the terephthaloyl diisocyanate in step N3 is replaced with 0.2 mol of benzoyl isocyanate; and the amount of intermediate 2 in step N4 is replaced with 0.103 mol.

[0048] Comparative Example 9 The raw material composition and preparation method of the antibacterial bioactive glass composite material for skull defect repair are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that the terephthaloyl diisocyanate in step N3 is replaced with an equimolar amount of terephthaloyl diisocyanate.

[0049] The bioactive glass used in the embodiments and comparative examples of this application is medical grade HQ-BG45s-D1, produced by Kunshan Huaqiao Science and Technology New Materials Co., Ltd.; the hydroxyapatite is HAP03-20, produced by Nanjing Junzhuo Biotechnology Co., Ltd.; the recombinant human collagen is recombinant type III humanized collagen, produced by Zhuhai Jibaikang Biotechnology Co., Ltd.; and the CAS number of terephthaloyl diisocyanate is 4418-78-4.

[0050] The antibacterial bioactive glass composite materials for skull defect repair prepared in Examples 5-7 and Comparative Examples 1-9 were tested, and the test results are shown in Table 1.

[0051] Bending strength test: The bioactive glass composite materials prepared in Examples 5-7 and Comparative Examples 1-9 were cut into specimens with dimensions of 45mm × 4mm × 3mm. The bending strength of the specimens was tested using an electronic universal testing machine with a loading speed of 0.5mm / min and a span of 20mm. The maximum load at which the specimen fractured was recorded, and the bending strength was calculated according to the following formula:

[0052] In the formula, 1 is the bending strength, MPa; F is the maximum load at which the specimen breaks, N; L is the span, mm; b is the width of the specimen, mm; h is the height of the specimen, mm.

[0053] Antibacterial performance test: The bioactive glass composite materials prepared in Examples 5-7 and Comparative Examples 1-9 were cut into uniform circular shapes (9 mm in diameter and 1 mm in thickness). These were placed in capped glass bottles containing PBS buffer (0.1 M, pH 7.4) and autoclaved at 121°C for 15 min. After cooling under ventilation, they were further sterilized by UV irradiation in a clean bench for 1 h. The tested bacterial strain was Staphylococcus aureus. Individual colonies were picked from the test strain and diluted with physiological saline to a bacterial concentration of 10⁻⁶. 8 CFU / ml. Drop 100 μl of bacterial suspension onto LB solid medium, spread the bacterial suspension evenly with a spreader, place the cut test sample on top, seal the plate and place it in a 37℃ biochemical incubator for constant temperature incubation. After 24 h, take it out and observe the bacterial growth on the medium and record the size of the inhibition zone.

[0054] Table 1 Performance Test Data

[0055] As can be seen from Table 1, the bioactive glass composite materials prepared in Examples 5-7 of this application have excellent flexural strength and antibacterial properties.

[0056] The toughening agent added to the components of the composite materials prepared in Examples 5-7 of this application is a three-arm topological structure with glycerol triglycidyl ether as the core. Each arm contains a hydroxyl group, a benzene ring, two acylhydrazone bonds, and a long-chain alkyl group attached to the acylhydrazone bonds. The three-arm topological structure provides a network support framework. The rigid benzene ring unit and the flexible long-chain alkyl group in each arm form a rigid-flexible synergistic system, dissipating external load energy through the elastic deformation and sliding of the molecular chain segments. The introduced acylhydrazone bonds serve as dynamic reversible covalent cross-linking points, absorbing impact energy through fracture under stress, and then undergoing reversible recombination triggered by temperature to achieve self-repair of microscopic damage, significantly improving the material's resistance to crack propagation. The hydroxyl group, as an interfacial functional group, can coordinate with the silanol groups and calcium ions of hydroxyapatite on the bioactive glass surface through hydrogen bonding, and form multiple intermolecular forces with the peptide chains of collagen, effectively transferring stress and inhibiting interfacial debonding. The various functional structural units in the toughening agent molecule work synergistically to improve the brittleness of the composite material through dynamic bond breaking energy dissipation, rigid-flexible chain segment synergistic deformation, and strong interfacial bonding, thus exhibiting excellent flexural strength.

[0057] The toughening agent used in Comparative Example 1 has a two-arm structure, which significantly reduces the network crosslinking density in the composite material. This weakens the multi-point anchoring ability with collagen, bioactive glass, and hydroxyapatite, resulting in decreased interfacial bonding. Simultaneously, the reduced number of dynamic hydrazone bonds decreases the energy dissipation efficiency of dynamic bond breakage under stress, and weakens the rigid-flexible synergistic deformation ability of molecular chain segments, failing to effectively transfer and disperse loads, ultimately leading to a decrease in the flexural strength of the composite material. The toughening agent used in Comparative Example 2 has a four-arm hyperbranched structure, leading to increased molecular steric hindrance, reduced entanglement and interpenetration ability with collagen, and excessive epoxy groups causing over-crosslinking, increasing the network rigidity and decreasing the flexibility of the composite material. Furthermore, the excessively high hydrazone bond density in the four-arm structure disrupts the dynamic bond breakage-reorganization balance, restricting the slip space of molecular chain segments under stress, reducing energy dissipation efficiency, and failing to effectively alleviate interfacial stress concentration, ultimately resulting in a decrease in the flexural strength of the prepared composite material.

[0058] The antibacterial agent added to the components of the composite materials prepared in Examples 5-7 of this application is based on a benzene ring, with quaternary ammonium salt cationic head groups, long alkyl chain hydrophobic tails, and pyridone heterocycles symmetrically attached to both ends via formylurea linkers. The synergistic effect of these structures achieves highly efficient and broad-spectrum antibacterial activity. Specifically, the quaternary ammonium salt cationic head group first firmly adsorbs onto the negatively charged bacterial cell membrane surface through electrostatic attraction, and the symmetrical design at both ends significantly improves the local cation concentration and adsorption efficiency. The long alkyl chain, acting as a hydrophobic tail, then inserts into the phospholipid bilayer, disrupting membrane integrity and causing leakage of contents, thus achieving rapid membrane lysis. The pyridone structure further disrupts the membrane structure by interfering with the activity of key bacterial enzymes and chelating metal ions through heterocyclic N / O atoms, synergistically enhancing membrane damage and effectively inhibiting biofilm formation. The formylurea group acts as a hydrogen bond donor and acceptor, enhancing molecular water solubility, surface affinity, and anchoring to the bacterial membrane, promoting stable accumulation and multi-site binding of the overall molecule on the membrane surface. The synergistic effect of various structures in the antibacterial agent molecule forms a "double-headed and double-tailed" configuration, which significantly improves membrane insertion efficiency, local high concentration effect and multi-mechanism bactericidal effect, thus enabling the composite material to exhibit excellent antibacterial properties.

[0059] In Comparative Example 7, when preparing the antibacterial agent, 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid was replaced with 5-methyl-4-oxopiridine-2-carboxylic acid. In the pyridone structure of the 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid molecule, the NH and C=O are located at the ortho position, which can form intramolecular hydrogen bonds, enhancing the binding ability with bacterial targets and more effectively disrupting cell membrane integrity. In contrast, in the pyridone structure of the 5-methyl-4-oxopiridine-2-carboxylic acid molecule, the NH and C=O are located at the para position, making it difficult to form intramolecular hydrogen bonds and thus unable to effectively interfere with cell membrane function, resulting in a decrease in the antibacterial performance of the final composite material. In Comparative Example 9, terephthaloyl diisocyanate was replaced with terephthalic diisocyanate. The resulting antibacterial agent molecule lacked acyl regulatory units, and the resulting linkage structure was dominated by a single urea bond. The number of carbonyl groups decreased, and the overall polarity and hydrogen bond donor-acceptor site density decreased. This led to a weakening of the spatial rigidity and electronic regulation ability of the formylurea bridging system. The distance and orientation between the two-terminal cationic head groups changed, making it difficult to maintain the ideal "double-headed and double-tailed" symmetrical configuration. At the same time, the anchoring ability and ordered arrangement ability of the molecule on the surface of the composite material were reduced, weakening the local cation enrichment effect and the hydrophobic chain insertion efficiency. This reduced the multi-site synergistic destruction ability of the bacterial membrane, ultimately resulting in a decrease in the antibacterial performance of the composite material.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. However, any modifications, alterations, and variations made by those skilled in the art without departing from the scope of the present invention based on the disclosed technical content are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. An antibacterial bioactive glass composite material for skull defect repair, characterized in that, The ingredients include the following parts by weight: Collagen 8-15 parts, bioactive glass 45-55 parts, hydroxyapatite 20-30 parts, toughening agent 5-8 parts, antibacterial agent 1-2 parts, deionized water 150-250 parts; The chemical structural formula of the toughening agent is as follows: ； The chemical structural formula of the antibacterial agent is as follows: 。 2. The antibacterial bioactive glass composite material for skull defect repair according to claim 1, characterized in that, The toughening agent is prepared by the following method: S1: Glyceryl glycerol triglycidyl ether reacts with 3,5-dicarboxylic acid to form intermediate A. S2: Intermediate A reacts with lauroyl hydrazine to generate a toughening agent.

3. The antibacterial bioactive glass composite material for skull defect repair according to claim 2, characterized in that, In step S1, the molar ratio of glycerol triglycidyl ether to 3,5-dicarboxybenzoic acid is 1:(3.01-3.03).

4. The antibacterial bioactive glass composite material for skull defect repair according to claim 2, characterized in that, In step S2, the molar ratio of intermediate A to lauroyl hydrazine is 1:(6.02-6.05).

5. The antibacterial bioactive glass composite material for skull defect repair according to claim 1, characterized in that, The antibacterial agent is prepared by the following method: N1: Dioctylmethyl tertiary amine reacts with epichlorohydrin to produce intermediate 1. N2: Intermediate 1 reacts with 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid to generate intermediate 2. N3: Terephthaloyl diisocyanate reacts with glycine to form intermediate 3. N4: Intermediate 2 reacts with intermediate 3 to generate an antibacterial agent.

6. The antibacterial bioactive glass composite material for skull defect repair according to claim 5, characterized in that, In step N1, the molar ratio of the dioctylmethyl tertiary amine to epichlorohydrin is 1:1.

01.

7. The antibacterial bioactive glass composite material for skull defect repair according to claim 5, characterized in that, In step N2, the molar ratio of intermediate 1 to 3-methyl-2-oxo-1,2-dihydropyridine-4-carboxylic acid is 1:1.

03.

8. The antibacterial bioactive glass composite material for skull defect repair according to claim 5, characterized in that, In step N3, the molar ratio of terephthaloyl diisocyanate to glycine is 1:2.

01.

9. The antibacterial bioactive glass composite material for skull defect repair according to claim 5, characterized in that, In step N4, the molar ratio of intermediate 2 to intermediate 3 is 2.05:

1.

10. A method for preparing an antibacterial bioactive glass composite material for skull defect repair according to any one of claims 1-9, characterized in that, Includes the following steps: (1) Weigh out the following by weight: 8-15 parts collagen, 45-55 parts bioactive glass, 20-30 parts hydroxyapatite, 5-8 parts toughening agent, 1-2 parts antibacterial agent, and 150-250 parts deionized water. (2) Deionized water and collagen were stirred and mixed, and bioactive glass, hydroxyapatite, toughening agent and antibacterial agent were added. After high pressure homogenization, freeze drying and sterilization, antibacterial bioactive glass composite material for skull defect repair was obtained.

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