摘要
目的探讨左旋聚乳酸(PLLA)与聚-L-丙交酯-己内酯(PLCL)的复合对PLCL的三维(3D)打印性能及其打印支架降解性能的影响。方法采用共混手段制备了系列不同比例的PLCL(100%、90%、80%、70%、60%、50%)为基质相、PLLA(10%、20%、30%、40%、50%、100%)为分散相的复合材料;利用熔融沉积成型(FDM)3D打印技术,制备不同比例、不同填充率(40%、50%、60%、70%)的PLCL/PLLA无边框3D多孔支架;通过支架宏/微观结构的观察及其体外加速降解实验,考察复合材料3D打印性能及其支架的降解性能。结果在研究条件下,复合材料均可打印成孔隙贯通的多孔支架,复合材料的孔径随填充率的增加而缩小,由40%时733μm缩小为70%时200μm。相对于单纯PLCL,复合PLLA更有利于支架结构成型。降解实验显示:PLCL支架降解较快,70%填充率打印支架60 d时降解达到88.58%,而PLLA的加入可以减慢支架降解速率;降解过程中,所有支架都较好地保持了原有结构的完整性,无明显断裂或崩解,但PLCL支架整体结构缩小、孔径增大明显,而复合PLLA明显改善了支架缩小和孔径增大的现象;微观形貌变化显示,PLCL支架表面在降解过程中出现了大量微孔结构,而PLCL/PLLA复合材料支架表面出现了微孔结构和微裂缝结构。结论复合PLLA不仅改善了PLCL的3D打印性能,而且也改变了复合材料支架的降解性能;通过改变PLCL和PLLA的比例及3D打印填充率,可以调控支架的孔径、孔隙率及降解速率,为多种组织、器官的工程化构建提供可选择的支架材料。
Objective To investigate the effect of the combination of L-polylactic acid(PLLA)and poly-L-lactide-caprolactone(PLCL)on three dimensional(3D)printability of PLCL and the degradation properties of the printed scaffold.Methods The series of composites with different ratios PLCL(100%,90%,80%,70%,60%,50%)as matrix phase and PLLA(10%,20%,30%,40%,50%,100%)as dispersed phase were prepared by blending method.PLCL/PLLA frameless 3D porous supports with different proportions and different filling rates(40%,50%,60%,70%)were prepared using fused deposition modeling(FDM)3D printing technique.The 3D-printability of composite material and degradation performance of the scaffold were investigated by observation of macro/micro structure and the accelerated degradation experiment in vitro.Results The composite materials were printed into porous scaffold with pore penetration,and the pore size decreased with the increase of filling rate,which from 733μm at 40%to 200μm at 70%.Compared with PLCL,composite PLLA was more conducive to scaffold structure molding.The degradation experiment results showed that PLCL degraded quickly,and degradation rate at 70%filling rate reached 88.58%at 60 d,while the addition of PLLA retarded degradation rate.During degradation,scaffold maintained integrity of original structure without obvious breakage or disintegration.However,the overall structure of PLCL scaffold were reduced and pore size increased significantly,while composite PLLA significantly prevent the shrinkage and pore size increase.The microscopic morphology changes showed that the large number of microporous structures appeared on surface of PLCL scaffold during degradation,while micropores and microcracks appeared on surface of PLCL/PLLA composite scaffold.Conclusion It is demonstrated that the composite PLLA improves 3D-printability of PLCL and also changes degradation performance of composite scaffold.By changing ratio of PLCL and PLLA and filling rate of 3D printing,pore size,porosity and degradation rate of scaffold can be controlled,which provide alternative scaffold materials for engineering construction of various tissues and organs.
作者
王自强
张逸芸
段瑞平
杜福崇
李学敏
WANG Zi-qiang;ZHANG Yi-yun;DUAN Rui-ping;DU Fu-chong;LI Xue-min(Institute of Biomedical Engineering,Chinese Academy of Medical Sciences&Peking Union Medical College,Key Laboratory of Biomedical Materials of Tianjin,Tianjin 300192,China)
出处
《生物医学工程与临床》
CAS
2021年第1期6-14,共9页
Biomedical Engineering and Clinical Medicine
基金
国家自然科学基金资助项目(81972043)
中国医学科学院医学与健康科技创新工程重大协同创新项目(2017-I2M-1-007)。
