Hydroxyapatite-Nanowires Enhanced Electrospun Fiber via Craze Disperse Stress for Bone Regeneration

摘要

Developing composite materials containing polylactic acid (PLLA) and hydroxyapatite (HA) has been a central issue in the orthopedic implant material because of their limited mechanical property which is caused by interface separation and heterogeneous dispersion in organic-inorganic composite materials. This research constructed a kind of craze disperse stress-based electrospun fibers containing hydroxyapatite nanowire, which could increase mechanical property and promote osteogenic differentiation and intravascular differentiation. The result illustrated that these composite fibers could not only consume stress energy but also stop the generation of cracks, by silver craze produced by the deformation of Hydroxyapatite nanowire. Moreover, the mechanical property of composite scaffold could be enhanced by the stress transmission between silver craze and microfiber. In addition, HA nanowires had the ability to increase PLLA fibers' hydrophilicity and promote the tensile strength of these complex fibers without making significant influence on the thermos ability of composite scaffold. Furthermore, these HA nanowires were beneficial to adhesion and proliferation of mesenchymal stem cells, and these nanowires can act as crystal nucleus to induce the deposition and growth of HA on the surface of compounded scaffold. Therefore, the composite PLLA's capability of promoting osteogenic differentiation and intravascular differentiation has been dramatically improved.