The calcium phosphate ceramic granules have been widely applied to fill irregular shaped bone defects in clinic due to their good biocompatibility, osteoconductivity, and osteoinductivity. In this work, we fabricated porous spherical calcium phosphate (Ca-P) nanoceramic granules with the assistance of sodium alginate and microwave hybrid sintering. Scanning electronic microscopy (SEM), X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), BET and mercury intrusion tests were employed to characterize the Ca-P nanoceramic granules. The SEM images revealed that grain size of the ceramic granules was on the nanoscale. The XRD and FT-IR results certified the phase composition of the Ca-P nanoceramic granules. The BET and mercury intrusion tests demonstrated that the porous spherical Ca-P nanoceramic granules had relatively high specific surface area and interconnected porous structure. Subsequently, the protein adsorption ability and cytocompatibility of porous spherical Ca-P nanoceramic granule were investigated. The obtained Ca-P nanoceramic granules show high ability of adsorbing proteins which implied that the granules might possess good osteoinductivity. Meanwhile, the porous nanoceramic granules could promote better cell adhesion, proliferation and differentiation compared with the conventional ones. Due to the relatively high porosity, nano-level surface topography, high specific surface area and protein adsorbing ability, interconnecting pore structure with abundant micropores and good cytocompatibility, the porous Ca-P nanoceramic spheres have potential to be a good candidate for bone defect filling materials.
National Basic Research Program of China (2011CB606201); National Natural Science Foundation of China (81190131); National Sci & Tech Support Plan of China (2012BAI17B01); National Sci & Tech Support Plan of China (2012BAI42G00)
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