Evaluation of electrospun biomimetic substrate surface-decorated with nanohydroxyapatite precipitation for osteoblasts behavior.

To engineer bone tissue, it is crucial to design scaffolds with micro- and nano-sized architecture imitating approximate hierarchical structure of native bone, and afford desirable biological properties by introducing biocompatible polymers and bioceramics into the scaffolds. Here, a novel scaffold consisting of poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV)/polyaspartic acid (PAA) was fabricated by electrospinning and nano-hydroxyapatite (nHA) was deposited by calcium-phosphate dipping process for bone tissue regeneration. Characterization of the prepared nanofibers revealed the formation of definite nHA crystal, porous structure of membranes, improved wettability with nHA deposition and satisfied mechanical properties. Human fetal osteoblasts were cultured on nanofibers and experienced in vitro evaluations of cell proliferation, adhesion and mineralization confirming the non-cytotoxicity and biocompatibility of scaffolds. Cells proliferation rate and ALP expression on PHBV/PAA-nHA were 36.40% and 40.14% higher than on PHBV/PAA, respectively. The utmost significance of this study is introducing bioactive PAA-nHA on polymeric nanofibers to regulate and improve specific cells adhesion, proliferation and mineralization of osteoblasts. All results indicate PHBV/PAA-nHA nanofibrous scaffolds can be applied as biomimetic platform for bone tissue repairation with appropriate physico-chemical properties, osteoinductivity and osteoconductivity.