Fabrication of zirconia/reduced graphene oxide/hydroxyapatite scaffold by rapid prototyping method and its mechanical and biocompatibility properties

Abstract

Zirconia (ZrO2) and hydroxyapatite (HA) are generally well-known for their good biological characteristics. This study evaluated the effect of reduced graphene oxide (RGO) alongside HA in the mechanical and biological properties of fabricated scaffolds. In this regard, after the synthesis of ZrO2/RGO/HA nanocomposite, 3D scaffolds were printed using the robocasting method. Characterizations were accomplished by X-ray diffraction (XRD), Fourier-transform infrared (FTIR), field emission scanning electron microscopy (FE-SEM), compersion test as well as cell toxicity test (MTT assay). The results of the compression test showed that 2%wt. of RGO as the reinforcement in ZrO2/HA matrix demonstrated the desirable behavior. However, the compressive strength of scaffolds was increased up to 64.37 MPa compared to 6.23 MPa in pure zirconia after heat treatment procedure. Moreover, by placing scaffolds in simulated body fluid (SBF), compressive strength was increased and reached 89.02 MPa in ZrO2/RGO/HA scaffold after 28 days. These variations in strength were caused by the nanocomposite materials being stimulated to ossify and produce calcium and phosphorus. Furthermore, the MTT assay of scaffolds shows that throughout the test, there was no negative cellular interaction between scaffolding and fat mesenchymal cells, and that these materials have a favorable impact on boosting cell adhesion. The introduced scaffold of ZrO2/RGO/HA can be used in bone tissue regeneration.