Indexed on: 09 Feb '16Published on: 09 Feb '16Published in: ACS Applied Materials & Interfaces
Natural origin bioceramics are widely used for bone grafts. In the present study, eggshells derived bioceramic scaffold is fabricated by 3D printing as a potential bone graft analogue. The eggshells, a biological waste material, was mixed with a specific ratio of phosphoric acid and chitosan as to form precursor towards the fabrication of osteoinductive, multi-phasic calcium phosphate scaffold via a coagulation assisted extrusion and sintering for multi-scalar hierarchical porous structure with improved mechanical properties. Physico-chemical characterization of the formed scaffolds was carried out for phase analysis, surface morphology and mechanical properties. The similar scaffold was prepared using chemically synthesized calcium phosphate powder which was compared with natural origin one. The higher surface area associated with interconnected porosity along with multiple phases of natural origin scaffold facilitated higher cell adhesion and proliferation as compared to chemically synthesized one. Further, natural origin scaffold displayed relatively higher cell differentiation activity as evident by protein and gene expression studies. On subcutaneous implantation for 30 days, promising vascular tissue in growth was observed circumventing major foreign body response. Collagen-rich vascular ECM deposition and osteocalcin secretion indicated bone-like tissue formation. Finally, the eggshell derived multi-phasic calcium phosphate scaffold displayed improvement in mechanical properties with higher porosity and osteoinductivity as compared to chemically derived apatite and unveil a new paradigm for utilization of biological wastes in bone graft application.