writer：7. Peibiao Zhang, Yang Cui, Zhi Wang, Xin Wang, Xiuli Zhuang, and Xuesi Chen
keywords：poly(lactide-co-glycolide), hydroxyapatite, nano-composite, bone repair
source：會(huì)議
specific source：The 5th Asian International Symposium on Biomaterials. Xiamen China, November 15~18
Issue time：2006年
Although hydroxyapatite (HA) ceramics has good osteoconductivity and osteoinductivity, the brittleness and fatigue failure in the body limit their clinical applications. Recent development of biodegradable polymers, mainly polyesters such as poly(L-lactic acid ) (PLLA), poly(glycolic acid) (PGA) and their copolymers (PLGA), is an attractive approach for tissue engineering with a wide range of mechanical properties, better biocompatibility and unlimited availability. Combination of HA particles and the polymers provides a new stragety to improve their biocompatibility and mechanical properties. However, the interface compatibility of the blend only left lower uniformity and limited mechanical properties. A novel nano-composites of PLLA/gHA were obtained in our lab through the hydroxyl groups on the surface of the HA nano-particles grafted with poly(L-lactide)(PLLA), and its blend with poly(lactide-co-glycolide) (PLGA) were achieved with higher mechanical property and stability. The blend was fabricated into porous scaffolds for bone tissue engineering by porogen leaching method. The growth factor(BMP-2) and RGD copolymer were incorporated into the scaffolds to improve their biological activities. Osteoblasts adhesion, growth and differentiation in the scaffolds were investigated by morphological analysis, RT-PCR and AKP detection. The scaffolds were seeded with autogenic MSCs of rabbits in vitro, and grafted to repair the bone defects of rabbits. The results showed that MSCs attached and grew well in the scaffolds in vitro, and new bones were formed and fused in the area of bone defects rapidly in animal tests. The material showed a wide application in tissue engineering and clinical orthopaedics.