纳米二氧化钛薄膜材料生物相容性的分析研究

发布时间：2018-06-27 16:54

本文选题：TiO_2纳米薄膜 + 成骨细胞　；参考：《华中师范大学》2012年硕士论文

【摘要】：硬骨组织修复材料是生物医用材料的一种,主要应用于诊断、治疗、修复和替换病损骨组织,增进老损骨组织的功能,是一类需求量大,市场前景广泛的材料。目前临床使用的硬骨组织修复材料组要为金属、生物陶瓷、生物玻璃和高分子聚合物支架,其寿命通常为10-15年。这样短的寿命为患者带来不便,也易引起二次痛苦。骨植入体在植入生物体后需要发生与周围组织的整合,其过程通常需要成骨细胞的大量粘附。成骨细胞早期大量粘附于植入体,细胞间迅速进行通信,完成细胞增殖、分化和其它生理功能,从而与生物体整合,发挥正常的生理功能。影响成骨细胞在材料表面早期粘附行为的因素包括材料表面的化学构成、拓扑形貌、粗糙度及亲水性等。研究表明,现有硬骨替代材料通常因为成纤维细胞包裹而导致发炎、坏死,使之无法发挥正常功能。而成纤维细胞和成骨细胞在材料表面的粘附比例显示与材料表面粗糙度有关,即材料表面粗糙度大时,成骨细胞易粘附,反之则造成成纤维细胞的大量附着。通过对生物材料表面改性,尤其是对表面粗糙度的改变可以提高成骨细胞在材料表面的粘附,提高植入体的成活率。对天然骨组织的研究发现,天然骨表面覆盖一层直径为1nm的胶原颗粒,这使得纳米材料作为骨植入材料的研究得到了强有力的理论支持。钛金属以及其合金材料是生物材料学的研究热点,纳米尺度钛材料显示出相对于其他金属材料的低毒性,受到全世界科学家的瞩目。目前对纳米二氧化钛材料的研究普遍集中于颗粒物质的体内、体外毒性研究,以及合金材料作为骨植入体的相关研究,对于表面覆盖纳米二氧化钛薄膜的钛基底材料的相关研究还较为少见。本实验分为两个部分,在第一部分中讨论了表面形貌分别为管状、网状、颗粒状的三种纳米二氧化钛薄膜材料在体外实验中的毒性测试,使用的实验手段包括扫描电子显微镜下观察材料表面粘附细胞的形态和数量,粘附细胞的乳酸脱氢酶泄露和细胞增殖。实验发现三种形貌的纳米二氧化钛薄膜材料中,颗粒状纳米二氧化钛覆盖的薄膜材料相对其他两种材料具有更高的细胞亲和力和较低的乳酸脱氢酶泄露,是相对理想的材料。第二部分实验承接第一部分实验的结果,着重讨论了表面覆盖1层、2层、3层、4层纳米二氧化钛颗粒的薄膜材料的生物相容性。实验采用国际流行的Layer-by-Layer自组装技术在纯钛基底表面组装不同层数的纳米二氧化钛颗粒,并使用扫面电子显微镜对材料进行表征,通过接触角分析实验对材料的亲水性进行检测。生物实验部分,采用鼠成骨瘤细胞与四种材料共培养,分别研究了材料表面粘附细胞的形貌和数量,使用荧光染料对粘附细胞内的ROS和DNA进行染色观察,测量了细胞乳酸脱氢酶泄露量和细胞增殖情况。结果发现材料表面粗糙度随着薄膜层数的增加而增大,亲水性也随之增大。而薄膜层数多的材料在生物学研究指标上也表现出优势,即薄膜层数越多,粗糙度越大的材料,其表面粘附细胞数量越多,细胞生长状况约好,受氧化损伤程度低,细胞凋亡和坏死现象少。
[Abstract]:Bone tissue repair material is a kind of biomedical material. It is mainly used to diagnose, treat, repair and replace the damaged bone tissue and improve the function of old bone tissue. It is a kind of material with large demand and wide market prospects. The clinical use of bone tissue repair materials in clinical use is for metal, bioceramics, Bioglass and polymer. Composite scaffolds usually have a life span of 10-15 years. Such short life can cause inconvenience to patients and cause two times of pain.
Bone implants need to integrate with the surrounding tissue after the implant is implanted. The process usually requires a large amount of adherence to the osteoblasts. Osteoblasts adhere to the implants in a large number of early stages, communicate rapidly between cells, complete cell proliferation, differentiation and other physiological functions, thus integrate with the organism and exert normal physiological functions. The factors of the early adhesion of bone cells on the surface of the material include the chemical composition of the surface of the material, the topologies, the roughness and the hydrophilicity, etc. research shows that the existing bone substitute materials are usually inflamed and necrotic, resulting from the inclusion of fibroblasts, which make it impossible to perform normal work. The adhesion ratio shows that the surface roughness of the material is related to the surface roughness of the material, that is, the osteoblast is easy to adhere to when the surface roughness is large, and on the contrary, it causes a large number of attachment of fibroblasts. By modifying the surface of the biomaterial, especially the surface roughness, the adhesion of osteoblast to the surface of the material can be improved and the survival rate of the implant is increased.
The study of natural bone tissue found that the surface of the natural bone covered a layer of collagen particles with a diameter of 1nm, which made the research of nanomaterial as a bone implant material. Titanium and its alloy materials are the hot spots in the study of biomaterials, and the nano scale titanium materials show relative to other metal materials. Low toxicity has attracted the attention of scientists all over the world. At present, the research of nanoscale titanium dioxide is generally concentrated in the body of particulate matter, in vitro toxicity research, as well as the related research of alloy materials as bone implants. The related research on the surface of titanium base materials covering nano titanium dioxide film is relatively rare.
The experiment is divided into two parts. In the first part, the toxicity test of three nano TiO 2 thin film materials with surface morphology, tubular, reticular and granular, is discussed in vitro. The use of the experimental means includes scanning electron microscope to observe the morphology and quantity of adhesion cells on the surface of the material, and the dehydrogenation of the adhesion cells. Enzyme leakage and cell proliferation. In the three morphologies of nanoscale titanium dioxide thin film materials, granular nanoscale titanium dioxide film materials have higher cell affinity and lower lactate dehydrogenase leakage relative to the other two materials, which are relatively ideal materials.
The second part of the experiment carried on the results of the first part of the experiment, and focused on the biocompatibility of the film materials covering 1 layers, 2 layers, 3 layers and 4 layers of nanoscale titanium dioxide particles. The experiment used the international popular Layer-by-Layer self-assembly technology to assemble different layers of nano titanium dioxide particles on the surface of pure titanium base and use sweep surface electricity. The material was characterized by a SUBMICROSCOPE and the hydrophilicity of the material was detected by the contact angle analysis experiment. In the biological experiment part, the rat osteoma cells were co cultured with four kinds of materials. The morphology and quantity of the adhesion cells on the surface of the material were studied, and the ROS and DNA were observed by the fluorescent dye. The results show that the surface roughness of the material increases with the increase of the number of film layers, and the hydrophilicity increases with the increase of the number of thin film layers. The more the film layers, the more the layers and the greater the roughness of the materials, the more the surface adhesion cells are. The growth of cells is good, the degree of oxidative damage is low, and the phenomenon of apoptosis and necrosis is small.
【学位授予单位】：华中师范大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.08

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