钛表面多级微钠米结构及其磷酸钙涂层制备与表征

发布时间：2019-03-24 11:01

【摘要】：钛及其合金因其高的比强度,耐腐蚀性能强及良好的生物相容性等优点,而被广泛用作人工骨、血管支架等生物植入金属材料。但是钛及钛合金植入体内后不易于骨组织发生有效地化学键合,故植入体易发生松动脱落,造成植入失败。研究表明,钛合金表面形貌,特别是表面微纳米结构可以有效模拟体内微纳米环境,促进蛋白质吸附与细胞的增殖粘附、分化等。所以,将钛表面改性,构建表面微纳米结构可以有效地提高钛合金与骨组织愈合速度,提高骨整合能力,促进新骨生成。磷灰石作为人体骨组织的主要无机成分,对骨组织的修复愈合有良好的促进作用,但是其力学性能较差。将二者有机结合起来,在钛合金表面沉积磷酸钙涂层,构建表面微纳米结构,不仅可以提高植入体的生物活性,增强骨组织与植入体之间的键合,而且弥补了生物陶瓷在力学方面的缺陷。首先,采用水热植酸处理,通过选取不同浓度植酸,在金属钛表面构建了多级微纳米结构,然后采用仿生矿化法在钛表面沉积了磷酸钙晶体,运用SEM、EDX、XRD等分析设备对其物相进行表征。结果显示：(1)不同浓度植酸水热处理得到的金属钛表面形貌,成分均有差异,当植酸浓度为5 v/v%时,表面生成了1-3μm的Ti02金红石结构,当植酸浓度为7.5 v/v%时,表面形成了微米／纳米相结合的沟槽状结构,当植酸浓度为10 v/v%时,表面形成了由片层状结构自组装形成的花瓣状结构,成分为Ti(HPO4)2与Ti(HPO4)2·H2O;(2)将三种不同的水热植酸处理赋予的微纳米结构表面采用浸渍法预钙化后,浸泡入过饱和钙磷溶液中,在其表面制备了磷酸钙涂层。其次,采用水热碱处理的方法,在钛表面制备钛纳米线状结构,然后通过二次水热处理在原有钛纳米线状结构表面原位沉积磷酸钙,且不改变原有钛纳米线结构。通过对其分析发现：(1)通过水热碱处理得到了均匀无裂纹,长度约为4-8μm,宽度约为50-200 nm的钛纳米线状结构；(2)通过二次水热处理,小分子模板剂H6L调控磷酸钙生长,在钛纳米线上原位沉积了磷酸钙,构建了具有多级微纳米结构的钛表面。最后将碱热处理钛表面纳米线结构样品与二次水热原位沉积磷酸钙样品进行蛋白吸附与成骨细胞实验。结果显示,钛表面微纳米结构样品均有利于牛血清蛋白的吸附；钛纳米线二次水热沉积磷酸钙构建的多级微纳结构表面更有利于成骨细胞增殖生长。
[Abstract]:Because of its high specific strength, corrosion resistance and good biocompatibility, titanium and its alloys have been widely used as biomaterials such as artificial bone, vascular scaffolds and so on. However, titanium and titanium alloy are not easy to be effectively chemically bonded in bone tissue after implantation, so the implant is easy to loose and fall off, resulting in the failure of implantation. The results show that the surface morphology of titanium alloy, especially the surface microstructure, can effectively simulate the in vivo micro / nano environment and promote the protein adsorption and cell proliferation, adhesion, differentiation and so on. Therefore, the titanium surface modification and the construction of the surface microstructure can effectively improve the healing rate of titanium alloy and bone tissue, improve the ability of bone integration, and promote the formation of new bone. Apatite, as the main inorganic component of human bone tissue, has a good effect on the healing of bone tissue, but its mechanical properties are poor. Combining them organically, depositing calcium phosphate coating on the surface of titanium alloy to construct the surface microstructure can not only enhance the bioactivity of the implant, but also enhance the bonding between bone tissue and implant. It also makes up for the mechanical defects of bioceramic. First of all, hydrothermal phytic acid treatment was used to construct multistage microstructure on titanium surface by selecting different concentration phytic acid. Then calcium phosphate crystal was deposited on titanium surface by biomimetic mineralization method, and SEM,EDX, was used to deposit calcium phosphate crystal on titanium surface. Its phase was characterized by XRD and other analytical equipment. The results show that: (1) the surface morphology and composition of titanium obtained by hydrothermal treatment with different concentration of phytic acid are different. When the concentration of phytic acid is 5 v / v%, the Ti02 rutile structure of 1-3 渭 m is formed on the surface. When the concentration of phytic acid was 7.5 v%, the surface formed a groove-like structure combined with micron / nano-meter. When the concentration of phytic acid was 10 v / v%, the surface formed a petal-like structure formed by lamellar self-assembly, and when the concentration of phytic acid was 10 v / v%, the surface formed a petal-like structure. The constituents were Ti (HPO4) 2 and Ti (HPO4) 2 路H2O; (2) calcium phosphate coating was prepared on the surface of three kinds of hydrothermal phytic acid treated micro-nanostructures by impregnation precalcification and immersion in supersaturated calcium-phosphorus solution. Secondly, titanium nanowires were prepared on the surface of titanium by hydrothermal alkali treatment, and then calcium phosphate was deposited on the surface of titanium nanowires by secondary hydrothermal treatment without changing the structure of titanium nanowires. It was found that: (1) Ti nanowires with a length of 4-8 渭 m and a width of 50 渭 nm were obtained by hydrothermal alkali treatment. (2) by secondary hydrothermal treatment, the growth of calcium phosphate was regulated by small molecular template H6L, calcium phosphate was deposited on titanium nanowires in situ, and the titanium surface with multi-stage micro-nano-structure was constructed. Finally, protein adsorption and osteoblast experiments were carried out between alkaline-heat-treated titanium nanowires and in-situ secondary hydrothermal deposition of calcium phosphate. The results showed that all the microstructure samples on titanium surface were favorable to the adsorption of bovine serum protein, and the multi-stage nano-nano structure surface constructed by secondary hydrothermal deposition of calcium phosphate on titanium nanowires was more favorable to the proliferation and growth of osteoblasts.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG174.4

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