可降解生物材料聚乳酸羟基乙酸仿生矿化的实验研究

Study on Biomimic mineralization of Poly Lactide-co-Glycolide

目的 :通过对聚乳酸 羟基乙酸共聚物 (polylactide co glycolide ,PLGA)的仿生矿化 ,表面改性 ,以提高其细胞粘附性 ;探讨影响仿生矿化的因素和条件 ,为进一步制备组织工程化人工骨提供依据和实验基础。方法 :PLGA膜经碱性溶液水解处理后 ,应用高温显微镜测量材料表面润湿角的变化 ;碱处理后的PLGA膜和三维多孔PLGA分别在模拟体液 (SimulatedBodyFluid ,SBF)中矿化 14d ,在 1 5倍SBF中矿化 9d ,应用扫描电镜进行矿化物形貌观察 ,X射线能谱分析钙磷比值 ,X射线衍射仪和傅立叶转换红外光谱仪行矿化物物相分析。结果 :PLGA经碱性溶液水解处理后表面亲水性明显增强 ,在SBF及 1 5倍SBF中矿化后表面可以形成明显的矿化物 ;矿化物的形态与矿化液的浓度有关 ;矿化物主要成分为羟基磷灰石 (HA) ,含有碳酸根成分 ,钙磷比为 1 5 3,类似于人骨无机质。结论 :PLGA仿生矿化是制备结构及性质类似骨基质人工骨的可行方法。

Objective: To construct a mineralized poly(lactide-co-glycolide) by biomimetic approach in order to improve the property of PLGA surface, and to develop biomaterials for orthopaedic tissue regeneration. Methods: PLGA films and 3-D porous PLGA were subjected to a hydrolysis treatment with alkaline solution prior to mineralization. The wettability of PLGA films were measured with high temperature microscope. PLGA hydrolyzed for 60 minutes were mineralized in SBF for 14 days or in 1.5 folds of the standard SBF for 9 days. The morphology, composition, and phase of mineral grown on PLGA were analyzed with SEM, FTIR and XRD. Results: The wettability of PLGA films was enhanced after being hydrolyzed by alkaline solution. The morphology of the mineral depended on the solution characteristics. The main component of mineral was hydroxyapatite containing a little of CO32- group, the Ca/P ratio was 1.53, similar to the major mineral component of bone tissue. Conclusion: Mineralization of PLGA by biomimic approach is a suitable way to construct bioactive artificial bone.