新型HA-PEC纳米复合骨修复材料的研制及细胞相容性研究

目的:制备一种新型的HA-PEC纳米复合骨组织缺损修复材料,并评价其细胞相容性。方法:将含有Ca、P离子(Ca/P的摩尔比为1.67,Ca~(2+)的终浓度为6 mmol/L)的酸性壳聚糖(chitosan,CS)溶液滴加入磷酸化壳聚糖(phosphorylated chitosan,PCS)溶液中,控制反应条件,获得由羟基磷灰石(hydroxyapatite,HA)和壳聚糖-磷酸化壳聚糖聚电解质复合物(polyelectrolyte complex,PEC)共同组成的HA-PEC微粒。HA-PEC复合物与成骨细胞共同培养,观察细胞黏附、生长的情况。结果:纳米级的、低结晶度的HA均匀地分布在PEC纤维中,"HA-PEC微粒"具有类骨的微孔结构,可促进成骨细胞黏附、增殖、分化。结论:"HA-PEC"纳米复合材料具有良好的生物相容性和降解性,有望成为一种有前途的新型骨组织修复材料。

Biomimetic Synthesis of a Novel Nano-composite of HA-PEC for Bone Repair and its Biocompatibility in vitro

Objective： To synthesize a novel nano-composite of hydroxyapatite （HA） and a polyelectrolyte complex （PEC） of chitosan and phosphorylated ehitosan ; and to evaluate its bioactivity in vitro. Methods： The HA-PEC nanoeomposite was prepared by a biomimetic method. An acidic chitosan solution containing calcium and phosphate ions （Ca/P=1.67, 6 mmol/L Ca^2＋） was added into phosphorylated chitosan solution to obtain HA-PEC composite which consisted of PEC and the controlled HA crystal. The material was co-cultured with rat osteoblasts in vitro to observe the adhesion and growth of cells. Results： The nano low erystalloid HA was evenly distributed in the PEC fibers with complicated porous structure. It can promote osteoblasts adhesion, proliferation, and differentiation in vitro. Conclusion： The osteoblasts response to the material histologically showed that it was bioaetive, as well as biodegradable. The HA-PEC composite shows the promise as a bone-repair material.