镁骨组织工程支架的打印制备及性能特征  

Preparation and characterization of printed magnesium scaffolds for bone tissue engineering

作　　者：李莹 伍权[1] 汤耿 李红[1] 尚立艳 Li Ying;Wu Quan;Tang Geng;Li Hong;Shang Li-yan(School of Mechanical and Electrical Engineering,Guizhou Normal University,Guiyang 550025,Guizhou Province,China)

机构地区：[1]贵州师范大学机械与电气工程学院,贵州省贵阳市550025

出　　处：《中国组织工程研究》2018年第6期827-832,共6页Chinese Journal of Tissue Engineering Research

基　　金：贵州省科学技术基金项目(黔科合J字[2014]2132号);贵州省优秀青年科技人才培养对象专项资金(黔科合人字[2015]05号);贵州省科技计划项目(黔科合LH字[2016]7221号);贵州师范大学资助博士科研项目(2014)~~

摘　　要：背景:传统的镁支架制备方法包括铸造法、粉末冶金法和激光加工等,但制备的支架在孔隙连通性、结构复杂性、个性化等方面存在缺陷。因此,探索多孔镁支架可控制备的新方法具有重要研究意义。目的:采用3D打印技术制备多孔镁支架,并研究其性能。方法:利用气动挤出式3D打印系统,将高稳定性的浆料(由镁粉、2-羟乙基纤维素、聚乙二醇、三油酸甘油酯、氨水、去离子水、无水乙醇组成)挤出打印成形,再结合保护气氛下高温烧结,实现镁支架的可控制备。通过扫描电镜观察支架微观形貌,X射线衍射测定物相组成,排水法测定支架孔隙率,万能材料试验机测量支架的力学性能。将镁支架浸泡于生理盐水中30 d,定期检测支架降解速率及浸泡液pH值。结果与结论:(1)多孔镁支架由规则的圆柱状丝条堆积而成,丝径与孔隙均为(450±50)μm,微观结构中均匀分布微米级孔洞,形成二级孔隙,支架孔隙率为(65.0±2.5)%,抗压强度达(0.87±0.15)MPa,支架物相主要为镁;(2)随着浸泡时间的延长,多孔镁支架的降解不断进行,降解速率逐渐趋于平稳,平均降解速率为(10.0±0.2)mm/年;0-5 d,随着浸泡时间的延长,浸泡液的pH值逐渐增大;5 d后趋于平稳,pH值保持在10.5±0.2;(3)结果表明,3D打印技术为多孔镁支架的可控制备提供了新方法。BACKGROUND:The traditional methods for preparing magnesium scaffolds include casting,powder metallurgy and laser processing technology.But these methods have some defects in pore connectivity,structure complexity,and personalization.Therefore,it is of great importance to explore a new method for the preparation of porous magnesium scaffolds.OBJECTIVE:To investigate the preparation and characterization of porous magnesium scaffolds fabricated by three-dimensional(3D)printing technology.METHODS:A magnesium porous scaffold was prepared by 3D printing.The high-stability magnesium paste(consisting of magnesium powder,2-hydroxyethyl cellulose,polyethylene glycol,glycerol trioleate,ammonia,deionized water and absolute ethanol)was extruded from the pneumatic extrusion printing system to construct the scaffold,which was then sintered under protective atmosphere.The scaffold microstructure was observed by scanning electron microscope.The phase composition of scaffold was observed by X-ray diffraction.The porosity was measured by drainage method.The compressive strength was measured by universal testing machine.The degradation was studied by immersing the scaffold in saline for 30 days,and the degradation rate and the pH value of soak solution were measured at regular intervals.RESULTS AND CONCLUSION:(1)The magnesium scaffold was piled up by cylindrical filaments,and both the sizes of filaments and the pores were(450±50)μm.Also,there were many micropores in the filaments that formed the secondary pores.The porosity of the scaffold was(65.0±2.5)%and the compressive strength was(0.87±0.15)MPa.The principal phase of the scaffold was magnesium.(2)The degradation of the scaffold continued with the soaking time,and the degradation rate showed a steady trend,which was(10±0.2)mm per year in average.The pH value of the soak solution increased in the first 5 days,and then the pH value was kept at 10.5±0.2.To conclude,3D printing technology provides a new method for porous magnesium scaffold preparation and application in bone t

关 键 词：生物相容性材料 镁 组织工程 

分 类 号：R318[医药卫生—生物医学工程]