【作者】 李伟；

【导师】 肖帆；

【作者基本信息】 浙江工业大学 ， 材料加工工程， 2012， 硕士

【摘要】 钛及其合金具有较高的机械性能和良好的生物相容性,作为种植体材料被广泛应用于人体硬组织的替换与修复等领域。钛金属本身不具备生物活性,需要通过表面改性处理赋予其生物活性,即在其表面覆盖一层二氧化钛薄膜,实现钛基体的活化。二氧化钛层主要通过钛基体表面自身的氧化获得,且多数制备过程中需要经过后续高温处理,这对于基体材料的选择以及处理后二氧化钛薄膜的生物活性都有影响。实现低温下制备晶态二氧化钛薄膜,避免后续高温处理,对保持薄膜的生物活性具有积极的作用。本文采用水解-胶溶法结合层层自组装技术,对纯钛基体进行表面改性,在其表面制备了中空球结构的二氧化钛薄膜。经过不同参数下紫外（UV）照射处理后,通过模拟体液（SBF）浸泡实验评价薄膜诱导羟基磷灰石的沉积能力。利用X射线衍射仪（XRD）、扫描电镜（SEM）、X射线能谱仪（EDS）和傅里叶红外光谱仪（FT-IR）等相关测试手段对改性后薄膜的物相组成、表面形貌、官能团等进行表征与分析。通过薄膜表面成骨细胞培养对薄膜的生物相容性和安全性进行评价。结果发现:1.在90°C下pH为1.02的处理溶液中成功制备了均一性高、分散性好的TiO₂/PS复合微球。利用高温煅烧和溶解挥发两种方法都可以获得表面结构完整的TiO₂中空球,模拟体液浸泡实验结果显示溶解组TiO₂中空球表面的生物活性要好于高温煅烧组。2.紫外照射能够增加TiO₂中空球表面活性Ti-OH基团的数量,提高了TiO₂中空球诱导羟基磷灰石沉积的能力。随着照射时间延长,薄膜的生物活性越好。照射介质对二氧化钛薄膜的生物活性也存在一定的影响。3.经过模拟体液浸泡和表面成骨细胞培养实验后,发现薄膜材料具有较好的羟基磷灰石沉积特性和细胞相容性,表明TiO₂中空球结构薄膜具有良好的生物活性。同时,薄膜材料对成骨细胞的损伤作用并不明显,细胞的生物合成能力良好,说明其生物安全性较好。更多还原

【Abstract】 As implant materials, titanium and its alloys have been widely used in human hard tissue replacement and repair due to their higher mechanical properties and excellent biocompatibility. Titanium metal without bioactivity must be surface modified to attain bioactivity, that is, its surface is covered with titania （TiO₂） thin film so as to achieve activation. Mainly the TiO₂ layer is obtained by oxidizing of titanium substrate itself. However, most of the preparation process contains heat treatment, which restricts the choice of substrate material and the bioactivity of TiO₂ films. The preparation of crystalline TiO₂ thin film at low temperature, without subsequent high temperature treatment, has a positive effect on maintaining the bioactivity of the film.In this thesis, TiO₂ thin films with the surface structure of hollow spheres were successfully prepared on Ti substrate by hydrolysis - gel method and layer-by-layer self-assembly technology. After ultraviolet （UV） irradiation in different parameters, induced hydroxyapatite deposition capacity of thin film was evaluated through simulated body fluid （SBF） immersion. The phase composition, surface morphology appearance, functional groups of modified films were characterized and analyzed by using X-ray diffraction （XRD）, scanning electron microscopy （SEM）, X-ray energy dispersive spectroscopy （EDS）, Fourier transform infrared spectroscopy （FT-IR） and other related tests. The osteoblasts culture on its surface was carried out so as to evaluate biocompatibility and safety of TiO₂ thin films. The research results as follow:1. TiO₂/PS composite microspheres with high uniformity and good dispersibility were successfully prepared on Ti substrate at 90°C in the pH 1.02 treatment solutions. TiO₂ hollow spheres with complete surface structure were attained by the two methods-calcination and dissolution. SBF immersion results show that the bioactivity of the dissolved group was better than the calcined group.2. UV radiation can increase the quantity of active Ti-OH groups on TiO₂ hollow spheres surface and enhance the ability to induce hydroxyapatite deposition of TiO₂ hollow spheres. With prolonged irradiation, the bioactivity of films improves. Irradiation media has a certain extent effect on the bioactivity of TiO₂ thin films. 3. Through simulated body fluid immersion and cell culture,TiO₂ thin films show excellent characteristics of hydroxyapatite deposition and in vitro cell compatibility, that is, TiO₂ hollow spheres thin films have good bioactivity. Meanwhile, the thin films don’t have obvious damage on the osteoblast, which have a good biosynthesis capacity. All these show the biosafety of TiO₂ thin films is good.更多还原