丝素羟基磷灰石支架材料的结构特性和机械性能研究.pdf

西南大学
硕士学位论文
丝素/羟基磷灰石支架材料的结构特性和机械性能研究
姓名:张胡静
申请学位级别:硕士
专业:特种经济动物饲养
指导教师:徐水;朱良均
20100501
中文摘要
丝素/羟基磷灰石支架材料
的结构特性和机械性能研究
特种经济动物饲养专业硕士研究生张胡静
指爭教师徐水副教授朱良均教授
摘要
随着骨修复材料需求量的不断增大,开发人工骨修复材料成为当前研究的热点问题。羟
基磷灰石与人类骨骼有相似的组成,能刺激骨细胞在其表面生长,植入后能被受体的骨细胞
不断代替。单纯羟基磷灰石支架脆性大、机械性能较差,不利于用作骨的修复材料。丝素由
18种氨基酸组成,相互排列成线性结构,具有良好的生物相容性和生物降解性。丝素/羟基磷
灰石复合材料在保持原有材料优势的基础上提高材料的力学性能,实现优势互补,有塑用作
人工骨修复材料的开发
本研究以丝素和羟基磷灰石为基材,磷酸盐缓冲液为溶剂,戊二醛为交联剂,通过调节复
合材料中丝素、羟基磷灰石的含量比,探索丝素/羟基磷灰石多孔支架的制备工艺,利用红外
光谱仪、X衍射分析仪、扫描电镜、万能试验机测定分析支架的物理化学结构和力学性能。结
果表明,丝素/羟基磷灰石复合材料具有结晶结构和B构象。当丝素与羟基磷灰石的比例为6/4
时,支架材料的弹性模量和压缩强度达到最大值,分别为48.087MPa和1.44MPa,孔隙率为
70%,支架孔径50~200um。利用该方法制备获得的支架材料,机械性能有明显提高,与人体
松质骨的结构接近。
为进一步优化制备工艺,提高材料的力学性能,研究中尝试调整丝素/羟基磷灰石支架制
备过程中的反应温度、干燥时间、制孔剂、戊二醛、甲醇添加比例以及材料固化时间、溶剂
pH值、浓度等因素,检测分析以上条件对材料成型效果及机械性能的影响。结果表明:浓度
和温度是影响材料机楲性能的重要因素。当固液比例为1:1时能达到最住共混效果,支架弹
性模量能达到74.98MPa,超过人体松质骨弹性模量理论要求。温度条件为40℃,湿度100%,
制得材料的力学性能相对其他温度更佳,为材料直接在人体体内成型的研究羹定基础。交联
剂戊二醛添加比例不断増加与材料的弹性模量也表现为上升趋势,但添加比例过大会增加材
料的毒性,实际制备中应保证机械性能的条件下降低成二醛含量。2%的甲醇含量将使材料弹
性模量得到最大程度提高。其中,孔隙率的提高将以降低材料机械性能为代价,制孔剂含量
增加使支架的力学性能成下降,可根据实际需要制备得到不同孔隙率的支架材料。为延长材
料的存放时间,可通过冷冻干燥降低材料的含水率,千燥时间为h支架获得最佳弹性模量。
其他条件对支架弹性模量的影响不大,可根据实际需要进行适当调整。
关键词:羟基磷灰石丝素蛋白骨修复材料多孔支架机械性能
bstract
Abstract
Finding the bone defect materials become the hot spot in the biomaterials field. Hydroxyapatite
with the similar compositions of the bone can be rapid fixed, bond between the osteogenesis and
scaffold, and replaced by the new osteoblast. These virtues have been verified in many mammal
experiments and clinic, but it too brittle, and easily crush in bone. Silk from the silkworm contains
eighteen different kinds of amino acid and some different structure, and used as the biomedical
suture for centuries. Its unique properties, such as biocompability, non-immunogenic response
controllable degradation in vino and robust mechanical properties provide its application in the
medical materials. Therefore, the mechanics will be increased by combining both HA and fibroin
which might be used in the field of human bone
In this study, the fibroin/hydroxyapatite scaffold is successfully prepared by dissolving both
fibroin and hydroxyapatite in the phosphate buffer, cross-linked by glutaral dehyde in moderate
condition which possesses both crystalline structure and p parallel. HA/SF composites were
investigated with Fourier transform infrared
spectroscopy(FTIR
),X-
difraction(XRD),asmi on electron microscop (TEM). Mechanical properties of the scaffold
were performed on AGS-J universal test machine. The result shows that the maximum elastic
modulus and compressive strength of this scaffold can attain about 48.087MPA and 1.44MPA
respectively, when the ration of fibroin/hydroxyapatite is 64. The porosity is 70%. The pore size
ranges from 50 Hm to 200 um. All the results suggest this new method can highly promote the
scaffolds mechanical properties which significant approach the cancellous bone of human
In order to find the optimal way to promote the scaffolds mechanical properties, we try to
change the temperature, time of the freezing dry, the proportion of NAHCO; lutaral dehyde
the time of the solidification, H and concentration and et al in the further field and analyze all of<