Reduced graphene oxide/nanohydroxy Apatite-Bismuth nanocomposites for osteogenic differentiation of human mesenchymal stem cells

Graphene/hydroxyapatite nanocomposites (NCs) is attracted more attention in bone tissue engineering due to their osteoconductive properties. Adding different ionic substitutions to graphene/hydroxyapatite NCs may increase its osteogenic properties. In this research study, bismuth doped hydroxyapatite nano-rods (Bi-nHA) were decorated on the reduced graphene oxide (rGO) sheets. The formation and structure of the nanocomposites (rGO/Bi-nHA) was characterized using the transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Inductively-coupled plasma optical emission spectroscopy (ICP-OES), and zeta potential. The characterization results revealed that the graphene is reduced and the nanocomposites are multilayer. Zeta potential of nanocomposite sheets is seen to be-23.1 mV. The cytotoxicity and osteoconductive effects of rGO/Bi-nHA nanocomposite on Human adipose derived stem cells (ADSCs) were examined using the MTT and calcium deposition assay. The results demonstrated that, the nanocomposites have no toxicity. Calcium deposition was observed at all concentrations and the highest calcium deposition is at 10 µg/mL. Based on the results of the synthesized nanocomposites, this material is suitable to be utilized in scaffold construction for bone tissue engineering.