天然高分子支架材料的酶控矿化及其用于骨诱导性能的研究

发布时间：2018-06-07 17:44

本文选题：骨组织工程 + 生物矿化　；参考：《暨南大学》2017年硕士论文

【摘要】：近年来,因先天性畸形、骨关节炎和意外事故中的创伤等原因所造成的骨缺损疾病患者数目日趋增多,其对骨组织工程移植材料的需求也随之逐渐增加。骨组织工程支架材料作为骨缺损和骨损伤材料的载体一直以来都是骨组织工程的灵魂。因此,成功制备出一种具有骨传导性和诱导性的理想型复合支架材料成为了修复骨缺损和骨损伤疾病的必要条件。根据天然骨的结构和组成,以天然活性高分子为模板仿生生物矿化法合成的天然高分子/羟基磷灰石复合支架材料是本研究领域的热点和核心。生物矿化方法能在一定程度上模拟出与天然骨具有相似形貌、尺寸和结晶度的磷灰石,并使复合支架材料达到良好的力学性能和生物活性。本论文在查阅了大量文献和结合课题组本身的研究基础上,选取了胶原(Collagen,COL)和壳聚糖(Chitosan,CS)两种天然生物活性高分子作为有机模板,利用透析法仿生矿化调控羟基磷灰石无机矿物在有机基质支架材料中的原位生成,制备出具有三维多孔结构和优异性能的有机-无机复合骨组织修复材料;也进一步研究比较了生物矿化体系中两种不同大分子有机模板对纳米羟基磷灰石(n-HAP)调控的差别,并在不添加生长因子和种子细胞的情况下,n-HAP/COL复合支架材料用于大鼠的背部皮下异位成骨实验的研究;nHAP/CS复合支架材料用于新西兰兔股骨缺损修复的研究,从而间接对比两种复合支架对骨再生和修复的情况。本论文通过选用不同的大分子有机基质模板,借助于XRD、FTIR、TEM、SEM、TG/DTG、孔隙率和压缩强度等测试的表征,研究了三维多孔支架材料的组成成分、结构、孔隙度、生物相容性和力学性能的变化;并将n-HAP/COL复合支架材料用于体内矿化实验和大鼠的背部皮下异位成骨实验的研究;而将n-HAP/CS复合支架材料用于MC-3T3成骨细胞的培养和新西兰兔后腿股骨缺损修复实验的研究。结果表明:两种复合支架材料表面和内部孔洞中都有丰富的钙磷盐的沉积且这些钙磷盐都为纳米级的羟基磷灰石,复合支架具有相互连通的孔隙结构和很好的力学强度,陈化72h的n-HAP/COL的孔隙率为72.78?0.23%,压缩强度和压缩模量分别为230.23?0.81kPa和465?0.9kPa;而透析72h的n-HAP/CS的孔隙率为96.7?1.0%,压缩强度和压缩模量分别为0.44?0.01MPa和0.20?0.01MPa。n-HAP/COL复合支架材料在体内研究初步证明了COL+Ca-GP组体内矿化的可行性,但COL+Ca-GP+体外ALP组无异位成骨能力;而n-HAP/CS复合支架材料在动物体内骨缺损研究表明与纯CS支架材料相比,n-HAP/CS复合支架材料更加能够完美地促进骨缺损的修复,在植入体内12周后,经Micro-CT和组织形态学染色观察证明n-HAP/CS实验组骨缺损修复基本完成。另外n-HAP/COL和n-HAP/CS两种复合支架材料在体内都具有良好组织相容性。
[Abstract]:In recent years, the number of patients with bone defects caused by congenital malformation, osteoarthritis and accidents is increasing, and the demand for bone tissue engineering transplantation has gradually increased. Bone tissue engineering scaffold material has always been bone tissue engineering as a carrier of bone defect and bone damage material. Therefore, the successful preparation of an ideal composite scaffold with bone conductivity and inducibility has become a necessary condition for the repair of bone defect and bone damage. Based on the structure and composition of natural bone, natural polymer / hydroxyapatite composite scaffold materials are synthesized by natural active polymer as template biomimetic biomineralization. The biomineralization method can simulate the apatite with similar morphology, size and crystallinity with the natural bone to a certain extent, and make the composite scaffold material achieve good mechanical properties and biological activity. This paper has been selected on the basis of a large number of literature and the research of the project group itself. Two kinds of natural bioactive polymers (Collagen, COL) and chitosan (Chitosan, CS) are used as organic templates to regulate the in-situ formation of hydroxyapatite inorganic minerals in organic matrix scaffold materials by dialytic biomimetic mineralization, and the organic and inorganic composite bone tissue repair materials with three-dimensional porous structure and excellent properties are prepared. Further studies and comparison of the differences in the regulation of nano hydroxyapatite (n-HAP) by two different macromolecular organic templates in the biomineralization system, and the study of the n-HAP/COL composite scaffold material used for ectopic osteogenesis in the back of rats without adding growth factors and seed cells; the nHAP/CS composite scaffold material was used in the new West. The study of the repair of the femur defect of the blue rabbit, in order to indirectly compare the situation of the bone regeneration and repair of the two composite scaffolds. In this paper, the composition, structure and pore of the three-dimensional porous scaffold are studied by using different macromolecule organic matrix templates and using the characterization of XRD, FTIR, TEM, SEM, TG/DTG, porosity and compression strength. The changes in degree, biocompatibility and mechanical properties; and the study of n-HAP/COL composite scaffold materials in vivo mineralization experiment and rat's back subcutaneous ectopic osteogenesis experiment. The n-HAP/CS composite scaffold materials were used in the culture of MC-3T3 osteoblasts and the study of the repair of the hind leg femur of New Zealand rabbits. The results showed that two kinds of composite scaffolds were used. There are abundant calcium and phosphorus salts deposited on the surface of the scaffold and the inner holes, and these calcium and phosphorus salts are nanometer hydroxyapatite. The composite scaffold has interconnected pore structure and good mechanical strength. The porosity of the n-HAP/COL of aging 72h is 72.78? 0.23%, the compressive strength and the compression modulus are 230.23? 0.81kPa and 465? 0.9 respectively. KPa, while the porosity of n-HAP/CS for dialysis 72h was 96.7? 1%, compression strength and compression modulus were 0.44? 0.01MPa and 0.20? 0.01MPa.n-HAP/COL composite scaffolds in vivo preliminarily proved the feasibility of mineralization in group COL+Ca-GP, but COL+Ca-GP+ in vitro ALP group had no bone formation ability; and n-HAP/CS composite scaffold was in animal body. The study of bone defect showed that compared with the pure CS scaffold material, the n-HAP/CS composite scaffold could improve the repair of bone defect perfectly. After 12 weeks of implantation, the Micro-CT and histomorphological staining showed that the repair of bone defect was basically completed in the n-HAP/CS experimental group. In addition, the two composite scaffolds of n-HAP/COL and n-HAP/CS were in the body. All of them have good histocompatibility.
【学位授予单位】：暨南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB324;R318.08

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