Department of Materials Science, Fudan University, Shanghai 200433, P. R. China.
Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai 200433, P. R. China.
ACS Appl Mater Interfaces. 2020 Mar 25;12(12):14365-14375. doi: 10.1021/acsami.9b20264. Epub 2020 Mar 13.
Exploiting the solid-state drawing (SSD) process toward polymer materials for medical implant devices is of significance to simultaneously improve the mechanical property and biocompatibility. Herein, for the first time, the bionic implants with a microvalley surface of oriented long chain branching PLA (b-PLA) was fabricated by a feasible SSD process. The as-obtained b-PLAs could not only show a high tensile strength (278.1 MPa) and modulus (4.32 GPa) but also bear a superior protein adsorption as high as 622 ng/cm. Such exceptional mechanical properties and biocompatibility could be ascribed to the SSD process-induced highly orientation degree and the morphology of parallel grooves within ridges structures, resulting in the greatly enhanced crystallinity and surface hydrophobicity as well as a biocompatible vascular endothelial microstructure for cell to adhesion and growth and thus an improved proliferation, differentiation, and activity of osteoblasts with spindle-shaped and spread morphology on surface of the b-PLAs. These findings may pave the way for designing the novel biomaterials for vascular stent or tissue engineering devices by the SSD process.
利用固态拉伸（SSD）工艺对用于医疗植入物的聚合物材料进行处理，对于同时提高机械性能和生物相容性具有重要意义。本文首次通过一种可行的 SSD 工艺，制备了具有定向长链支化 PLA（b-PLA）微峡谷表面的仿生植入物。所获得的 b-PLA 不仅表现出较高的拉伸强度（278.1 MPa）和模量（4.32 GPa），而且能够承受高达 622ng/cm 的优异蛋白质吸附。这种出色的机械性能和生物相容性可归因于 SSD 工艺诱导的高度取向度和脊结构内平行沟槽的形态，从而大大提高了结晶度和表面疏水性，并具有生物相容性的血管内皮微观结构，有利于细胞黏附和生长，从而改善成骨细胞的增殖、分化和活性，使其在 b-PLA 表面呈现出梭形和展开的形态。这些发现可能为通过 SSD 工艺设计新型血管支架或组织工程器件的新型生物材料铺平道路。
