Department of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, People's Republic of China.
Int J Nanomedicine. 2013;8:1855-65. doi: 10.2147/IJN.S43706. Epub 2013 May 9.
Poly(lactic-co-glycolic acid) (PLGA) is excellent as a scaffolding matrix due to feasibility of processing and tunable biodegradability, yet the virgin scaffolds lack osteoconduction and osteoinduction. In this study, nano-hydroxyapatite (nHA) was coated on the interior surfaces of PLGA scaffolds in order to facilitate in vivo bone defect restoration using biomimetic ceramics while keeping the polyester skeleton of the scaffolds.
PLGA porous scaffolds were prepared and surface modification was carried out by incubation in modified simulated body fluids. The nHA coated PLGA scaffolds were compared to the virgin PLGA scaffolds both in vitro and in vivo. Viability and proliferation rate of bone marrow stromal cells of rabbits were examined. The constructs of scaffolds and autogenous bone marrow stromal cells were implanted into the segmental bone defect in the rabbit model, and the bone regeneration effects were observed.
In contrast to the relative smooth pore surface of the virgin PLGA scaffold, a biomimetic hierarchical nanostructure was found on the surface of the interior pores of the nHA coated PLGA scaffolds by scanning electron microscopy. Both the viability and proliferation rate of the cells seeded in nHA coated PLGA scaffolds were higher than those in PLGA scaffolds. For bone defect repairing, the radius defects had, after 12 weeks implantation of nHA coated PLGA scaffolds, completely recuperated with significantly better bone formation than in the group of virgin PLGA scaffolds, as shown by X-ray, Micro-computerized tomography and histological examinations.
nHA coating on the interior pore surfaces can significantly improve the bioactivity of PLGA porous scaffolds.
聚（乳酸-共-乙醇酸）（PLGA）作为支架基质具有良好的可加工性和可调节的生物降解性，但原始支架缺乏骨传导性和骨诱导性。在这项研究中，纳米羟基磷灰石（nHA）被涂覆在 PLGA 支架的内表面上，以利用仿生陶瓷促进体内骨缺损的修复，同时保持支架的聚酯骨架。
制备 PLGA 多孔支架，并通过在改良的模拟体液中孵育进行表面改性。将涂有 nHA 的 PLGA 支架与原始 PLGA 支架进行体外和体内比较。检查兔骨髓基质细胞的活力和增殖率。将支架和自体骨髓基质细胞的构建体植入兔模型中的节段性骨缺损中，观察骨再生效果。
与原始 PLGA 支架相对光滑的孔表面相比，通过扫描电子显微镜发现涂有 nHA 的 PLGA 支架内孔表面具有仿生分级纳米结构。在涂有 nHA 的 PLGA 支架中接种的细胞的活力和增殖率均高于 PLGA 支架中的细胞。对于骨缺损修复，在植入涂有 nHA 的 PLGA 支架 12 周后，桡骨缺损完全恢复，与原始 PLGA 支架组相比，骨形成明显更好，X 射线、微型计算机断层扫描和组织学检查结果均显示如此。
在内部孔表面涂覆 nHA 可以显著提高 PLGA 多孔支架的生物活性。
