钛表面氨基杂化介孔硅基纳米形貌保护涂层的构建及成骨效果评价

Preparation of an amino hybrid mesoporous silica-based nanotopography protective coating on a titanium implant surface and evaluation of its osteogenic effect

摘要

目的 在钛纳米管（titanium nanotube，TNT）形貌表面原位沉积可降解的氨基杂化介孔硅（amino-hybrid mesoporous silica，AHMS），探讨其对纳米形貌的保护作用及成骨效应。方法 通过阳极氧化法和油水两相法依次制备TNT、TNT@AHMS作为实验组，以酸蚀钛作为对照组（Ti）；通过改变硅源用量比探索合成参数（3∶1，1∶1，1∶3）；扫描电镜观察其表面形貌、水接触角测定仪测定亲水性、X射线光电子能谱仪分析元素组成；利用纳米压痕检测及超声震荡仪体外观察TNT@AHMS机械强度形貌保持效果；体外模拟浸泡实验观察其降解行为；利用MC3T3-E1细胞系观察细胞在材料表面的黏附、增殖和分化能力；利用SD大鼠股骨植入模型和Micro-CT验证AHMS对TNT形貌的保护作用及骨结合效果。结果 TNT、TNT@AHMS形貌均制备成功，硅源用量比为1:3；扫描电镜可见钛纳米管间均匀覆盖AHMS涂层，介孔径约4 nm；AHMS掺入后材料表面为亲水性（12.78°），可检测到氨基基团（NH₂-）存在，并在体外12 h内即可降解完全，从而重新暴露TNT活性形貌，累计硅释放量为10 ppm；纳米压痕检测表明TNT@AHMS具有更理想的表面机械强度。电镜观察可见TNT在AHMS的保护下较好地保持了自身形貌，而TNT组出现了严重剥脱。此外TNT@AHMS表面细胞的早期黏附、增殖，ALP活性以及植入4 周后的骨体积分数均显著高于TNT组。结论 表面沉积AHMS可以起到保护TNT纳米形貌的作用，在发挥其生物学功效的同时，还进一步增强了成骨能力。该方案为未来纳米形貌修饰钛种植体的研发提供了新的思路。

Abstract

Objective To deposit degradable amino-hybrid mesoporous silica (AHMS) in situ on the surface of titanium nanotube (TNT) and explore its protective effect on nanomorphology and osteogenesis. Methods TNT and TNT@AHMS were sequentially prepared via an anodizing method: the oil-water two-phase method (experimental group) and the acid-etched titanium method [control group (Ti)]. The parameters for synthesis were explored by changing the silicon source dosage ratio (3∶1, 1∶1, 1∶3); the surface morphology was observed by scanning electron microscope(SEM), hydrophilicity was detected by Water Contact Angle Tester, elemental composition was detected by X-ray photoelectron spectroscopy (XPS); nanoindentation test and ultrasonic oscillator were used to observe the morphological holding effect as mechanical strength of TNT@AHMS in vitro; simulated immersion experiments in vitro was used to observe the degradation behavior of the material. the MC3T3-E1 cell line was used to observe the effect of cell adhesion, proliferation and differentiation on the material; and an SD rat femoral implant model and micro-CT were used to verify the protective effect and osseointegration effect of AHMS on TNT morphology. Results The morphologies of TNT and TNT@AHMS were successfully prepared, and the silicon source ratio was 1:3. SEM showed that the titanium nanotubes were uniformly covered with AHMS coating, and the mesoporous pore size was about 4 nm. After AHMS was incorporated, the surface of the material was hydrophilic (12.78°), the presence of amino groups (NH₂-) was detected, the material was completely degraded within 12 h in vitro, and the active morphology of the TNT was re-exposed with a cumulative silicon release of 10 ppm. Nanoindentation test showed that TNT@AHMS exhibited more ideal surface mechanical strength. SEM revealed that TNT maintains its own morphology under the protection of AHMS, and the TNT group suffered severe exfoliation. In addition, the early adhesion and proliferation rates, ALP activity, and bone volume fraction of cells on the TNT@AHMS surface 4 weeks after implantation were significantly higher than those in the TNT group. Conclusion By depositing AHMS on the surface of TNT, the nanotopography can be protected. It not only prevents the active base topography from exerting subsequent biological effects but also further endows the material with the ability to promote bone regeneration, laying a foundation for the future development of nanotopography-modified titanium implants.

关键词

钛种植体 / 介孔硅材料 / 纳米涂层 / 氨基化 / 形貌诱导 / 成骨细胞 / 细胞黏附 / 骨结合

Key words

titanium implant / mesoporous silicon material / nanocoating / amination / topography induction / osteoblast / cell adhesion / osseointegration

Author summay

杜诗敏，医师，硕士，Email：[e-mail]