The synthesis of eggshell-derived nano- and microscale hydroxyapatite bioceramic bone grafts

Abstract

Biografts were produced by adding the ground recycled eggshell powder at different ratios of micron and nanoscale hydroxyapatite (HA) powder. The effects of different wt% eggshell and HA powders on morphological and mechanical properties of the sol-gel-derived bone grafts were evaluated. The produced grafts were characterized via XRD, FTIR, SEM, EDX and mechanical tests. The addition of eggshell at different rates into the HA increased the mechanical properties of the produced biografts. Also, it was determined that the biograft M-H30Y40 had the maximum compression stress (190 MPa) and biograft N-H30Y40 had the maximum hardness (6.31 GPa), while the biograft M-H30Y40 had the minimum hardness (2.96 GPa) and N-H30Y30 had the minimum compressive stress (60.7 MPa). A uniform grain distribution was observed in nano- and microscale HA biografts. Non-porous structure was formed for microscale HA with eggshell-derived powder. However, low amount of porous structure was developed with nanoscale HA where the porosity decreased with increased wt% eggshell powder.