Characterization of robocasted graphene and graphene oxide reinforced scaffold structures for bone regeneration

Robocasting is a highly effective method to fabricate 3D bone scaffolds for bone tissue regeneration as it offers precise material deposition and great control over pore size and interconnectivity at low cost. In this study, bentonite (BEN)–hydroxyapatite (HAP) scaffolds reinforced with graphene (G) and graphene oxide (GO) in varying concentrations separately were fabricated through robocasting. All the fabricated scaffolds were sintered at 1100 °C. However, the BEN–HAP scaffolds (BH) were sintered in normal air and a controlled Argon atmosphere was used for the GBH and GOBH scaffolds. The printed samples were subjected to physical and mechanical characterizations. The results revealed that the higher concentrations of G and GO (2GBH and 2GOBH) resulted in decreased density and modified water absorption patterns. The compression test among the scaffold groups shows higher strength in graphene reinforced scaffolds than graphene oxide, making them appropriate for load-bearing bone tissue engineering applications. FTIR and XRD data revealed the chemical and structural changes in the scaffolds. The rough surface morphology of the printed scaffolds was analysed via FESEM. The EDAX data confirmed the presence of calcium, iron, alumina, magnesium, silica, phosphate, and sodium ions in both the GBH and GOBH scaffolds. The assessment of biological characterization through MTT and live–dead assays shows no cytotoxic effect among the scaffolds. However, the higher concentrations of graphene oxide were shown to reduce the cell viability. The findings of this study emphasize the interplay between scaffold composition, structural properties, and biological outcomes.