Bioinspired Surface Functionalization for Improving Osteogenesis of Electrospun Polycaprolactone Nanofibers

Electrospun nanofibers, with a typical interconnected porous structure mimicking the extracellular matrix, are commonly used in bone tissue engineering. However, to the best of our knowledge, few studies have been reported to investigate the enhancement of osteogenesis capability of electrospun polycaprolactone (PCL) nanofibers based on bioinspired surface functionalization. In this study, a universal and versatile approach was proposed to spontaneously modify the electrospun PCL nanofibers with bioactive nano-hydroxyapatite (nHA), using dopamine as an effective bioadhesive agent. The evaluation of scanning electron microscopy, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and surface wettability indicated that nHA was successfully coated onto electrospun nanofibers (PCL-PDHA). Furthermore, in vitro cell experiment including adhesion, proliferation, and osteogenic capability and in vitro biomineralization test in simulated body fluid revealed that the PCL-PDHA nanofibers were biocompatible to MC3T3-E1 cells, and the osteogenesis and biomineralization capabilities were greatly improved in comparison with that of PCL nanofibers. In summary, the facile bioinspired surface functionalization method introduced in the present study, due to its universality and versatility, not only can be used to improve osteogenesis of electrospun nanofibers but also can be regarded as an avenue to achieve other predesigned purposes in biomedical engineering.