Morpho-structural and compressive mechanical properties of graphene oxide reinforced hydroxyapatite scaffolds for bone tissue applications

Abstract

Hydroxyapatite (HA) is a unique material that has the potential to be used to replace bones and teeth in the field of orthopedics and dentistry since HA exhibits quite similar biological and chemical characteristics to human bone. Hydroxyapatite ceramics are bioactive materials used to repair damaged human tissue. The pores in the porous hydroxyapatite ceramics provide a mechanical interlock, enabling a solid bond and fixation between the implant and bone. In this study, 0.5wt%, 1wt%, and 1.5wt% graphene oxide (GO) reinforced porous HA structures were obtained using the space-holder method to increase the strength of hydroxyapatite with low mechanical strength. NaCl was used as a spacer, and PEG 400 as a binder. Scaffold structures with 40% porosity rates were sintered at 1000 ᵒC under vacuum. Finally, a compression test was applied to the samples which were previously analyzed by SEM, EDS and XRD. The compressive strengths of 0.5%, 1%, and 1.5% graphene oxide reinforced porous HA samples were determined between 8.04 and 31.14 MPa. The highest compressive strength was recorded as 31.14 MPa in the 1% GO added sample, and the lowest compressive strength was recorded as 8.04 MPa in the 1.5% GO added sample. In addition, it was understood that the mechanical properties did not increase regularly with the increase of graphene oxide reinforcing.