Department of Materials, The University of Manchester, Manchester M13 9PL, UK.
Department of Physics & Astronomy, The University of Manchester, Manchester, M13 9PL, UK.
Mater Sci Eng C Mater Biol Appl. 2020 Nov;116:111168. doi: 10.1016/j.msec.2020.111168. Epub 2020 Jun 6.
In order to provide a favourable environment for living bone formation, it is an essential condition to grow bone-like apatite layer at the interface between the tissue-implant and its surrounding tissues. Inspired by the chemical composition and the nano porous structure of natural bones, we developed an ultrafast and accessible route to accelerate effectively the formation of bone-like apatite on the surface of porous poly(l-lactic acid)-hydroxyapatite (PLLA-HA) composite fibres in 5 times simulated body fluid (5SBF). The key of the method lays in successful exposure of HA nanoparticles on the surface of PLLA fibres by acetone treatment of electrospun PLLA-HA nano/micro fibres. The recrystallization of PLLA chains uncovers more HA nanoparticles on the surface of every fibre which provide nucleation sites for calcium and phosphate ions. After only 2 h of immersing in 5SBF, a full layer of apatite completely covered on the surface of porous PLLA-HA fibres. The results indicate that HA nanoparticles on porous fibre surface can accelerate the kinetic deposition of apatite on fibre surface. Biological in vitro cell culture with human osteoblast-like cell for up to 7 days demonstrates that the incorporation of HA nanoparticles on the surface of porous PLLA fibrous membranes leads to significant enhance osteoblast adhesion and proliferation. The route can open avenues for development of fibrous PLLA biomaterials for hard tissue repair and substitution.
为了给活体骨形成提供有利的环境，在组织-植入物及其周围组织的界面处生长类似骨的磷灰石层是一个必要条件。受天然骨的化学成分和纳米多孔结构的启发，我们开发了一种超快速且易于实施的方法，可在 5 倍模拟体液（5SBF）中有效加速多孔聚（L-乳酸）-羟基磷灰石（PLLA-HA）复合纤维表面类似骨的磷灰石的形成。该方法的关键在于通过对静电纺 PLLA-HA 纳米/微纤维进行丙酮处理，成功地将 HA 纳米颗粒暴露在 PLLA 纤维表面上。PLLA 链的重结晶使每根纤维表面上的更多 HA 纳米颗粒暴露出更多的钙和磷酸盐离子成核位点。在 5SBF 中仅浸泡 2 小时后，完全覆盖在多孔 PLLA-HA 纤维表面的磷灰石层。结果表明，多孔纤维表面上的 HA 纳米颗粒可以加速磷灰石在纤维表面上的动力学沉积。体外细胞培养实验表明，将 HA 纳米颗粒掺入多孔 PLLA 纤维膜表面可显著增强成骨细胞的黏附与增殖。该方法为用于硬组织修复和替代的纤维状 PLLA 生物材料的开发开辟了新途径。
