Hong Zhongkui, Zhang Peibiao, Liu Aixue, Chen Li, Chen Xuesi, Jing Xiabin
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
J Biomed Mater Res A. 2007 Jun 1;81(3):515-22. doi: 10.1002/jbm.a.31038.
To improve the mechanical properties of the composites of poly(lactide-co-glycolide) (PLGA, LA/GA = 80/20) and the carbonate hydroxyapatite (CHAP) particles, the rice-form or claviform CHAP particles with 30-40 nm in diameter and 100-200 nm in length were prepared by precipitation method. The uncalcined CHAP particles have a coarse surface with a lot of global protuberances, which could be in favor of the interaction of the matrix polymer to the CHAP particles. The nanocomposites of PLGA and surface grafted CHAP particles (g-CHAP) were prepared by solution mixing method. The structure and properties of the composites were subsequently investigated by the emission scanning electron microscopy, the tensile strength testing, and the cell culture. When the contents of g-CHAP were in the range of 2-15 wt %, the PLGA/g-CHAP nanocomposites exhibited an improved elongation at break and tensile strength. At the 2 wt % content of g-CHAP, the fracture strain was increased to 20% from 4-5% for neat PLGA samples. Especially at g-CHAP content of 15 wt %, the tensile strength of PLGA/g-CHAP composite was about 20% higher than that of neat PLGA materials. The tensile moduli of composites were increased with the increasing of filler contents, so that the g-CHAP particles had both reinforcing and toughening effects on the PLGA composites. The results of biocompatibility test showed that the higher g-CHAP contents in PLGA composite facilitated the adhesion and proliferation properties of osteoblasts on the PLGA/g-CHAP composite film.
为改善聚（丙交酯-共-乙交酯）（PLGA，LA/GA = 80/20）与碳酸羟基磷灰石（CHAP）颗粒复合材料的力学性能，采用沉淀法制备了直径为30 - 40 nm、长度为100 - 200 nm的米粒状或棒状CHAP颗粒。未煅烧的CHAP颗粒表面粗糙，有许多整体凸起，这有利于基体聚合物与CHAP颗粒的相互作用。通过溶液混合法制备了PLGA与表面接枝CHAP颗粒（g-CHAP）的纳米复合材料。随后通过发射扫描电子显微镜、拉伸强度测试和细胞培养对复合材料的结构和性能进行了研究。当g-CHAP的含量在2 - 15 wt%范围内时，PLGA/g-CHAP纳米复合材料的断裂伸长率和拉伸强度有所提高。在g-CHAP含量为2 wt%时，断裂应变从纯PLGA样品的4 - 5%增加到20%。特别是在g-CHAP含量为15 wt%时，PLGA/g-CHAP复合材料的拉伸强度比纯PLGA材料高约20%。复合材料的拉伸模量随填料含量的增加而增加，因此g-CHAP颗粒对PLGA复合材料具有增强和增韧作用。生物相容性测试结果表明，PLGA复合材料中较高的g-CHAP含量促进了成骨细胞在PLGA/g-CHAP复合膜上的黏附与增殖性能。
