Preparation and characterization of vertically arrayed hydroxyapatite nanoplates on electrospun nanofibers for bone tissue engineering

• A novel nylon 6/hydroxyapatite (N6/HA) composite membrane scaffold.
• Vertically aligned and homogeneous distribution of HA nanoplates coated the scaffold.
• Crystal growth of HA nanoplates was carried out via a hydrothermal approach.
• Coatings of HA nanoplates on N6 fibers matrix definitely favored cells proliferation.

The aim of this study is to develop a facile and an efficient approach for providing the electrospun nanofibers scaffold with a vertically well-aligned and homogeneous distribution of hydroxyapatite (HA) nanoplates that coat the scaffold while maintaining its fibrous and porous structure. Crystal growth of HA nanoplates from a colloidal solution onto the surface of nylon (N6) nanofibers was carried out via a hydrothermal approach. The factors affecting the scaffold’s morphology, macrostructure and the interfacial bonding between the constituents as well as the influence of crystal size were characterized and well elucidated. The results revealed that the deposition of dense and thick uniform nanoplates was perpendicular and nucleated in a parallel configuration onto the longitudinal axes of the individual nanofibers during the treatment process. The sizes of the nanoplates, which are strongly dependent on the reaction time, were 30 and 95 nm in length, with thicknesses of 17–19 nm, after 2 and 3 h respectively. The nanoplates improve the mechanical properties of the HA/N6 biocomposite scaffolds. The surface properties of the fabricated scaffolds appeared to have a greater effect on the early stages of osteoblast behavior (cell attachment and proliferation). The cells attached, grew and proliferated faster on culture-coated scaffolds in comparison with the pristine ones. Our results indicate that the treated scaffolds fulfill the basic requirements of bone tissue engineering scaffolds, and have the potential to be applied in orthopedic and reconstructive surgeries.