Silicate-doped nano-hydroxyapatite/graphene oxide composite reinforced fibrous scaffolds for bone tissue engineering

Abstract

In this study, novel graphene oxide–incorporated silicate-doped nano-hydroxyapatite composites were prepared and their potential use for bone tissue engineering was investigated by developing an electrospun poly(ε-caprolactone) scaffold. Nanocomposite groups were synthesized to have two different ratios of graphene oxide (2 and 4 wt%) to evaluate the effect of graphene oxide incorporation and groups with different silicate-doped nano-hydroxyapatite content was prepared to investigate optimum concentrations of both silicate-doped nano-hydroxyapatite and graphene oxide. Three-dimensional poly(ε-caprolactone) scaffolds were prepared by wet electrospinning and reinforced with silicate-doped nano-hydroxyapatite/graphene oxide nanocomposite groups to improve bone regeneration potency. Microstructural and chemical characteristics of the scaffolds were investigated by X-ray diffraction, Fourier transform infrared spectroscope and scanning electron microscopy techniques. Protein adsorption and desorption on material surfaces were studied using fetal bovine serum. Presence of graphene oxide in the scaffold, dramatically increased the protein adsorption with decreased desorption. In vitro biocompatibility studies were conducted using human osteosarcoma cell line (Saos-2). Electrospun scaffold group that was prepared with effective concentrations of silicate-doped nano-hydroxyapatite and graphene oxide particles (poly(ε-caprolactone) – 10% silicate-doped nano-hydroxyapatite – 4% graphene oxide) showed improved adhesion, spreading, proliferation and alkaline phosphatase activity compared to other scaffold groups.