Modification of surfaces of alumina-zirconia porous ceramics with Sr2+ after SBF

Abstract

The modification of porous ceramic scaffold surfaces has been extensively studied to improve the osseointegration of implants. The biomimetic method remains among the most common modification techniques of porous ceramics. However, the calcium phosphates commonly formed by the biomimetic method have long degradation times, which can lead to the detachment of the bone tissue formed in vivo. Therefore, the aim of this project was to modify the surface of Al2O3 scaffolds with calcium phosphate minerals and strontium using the biomimetic method. The scaffolds were chemically treated using 5-M H3PO4 solution and then immersed in 5× simulated body fluid solution for 14 days. For the incorporation of strontium, they were immersed in an aqueous solution of 100 ppm analytical grade Sr(NO3)2 under magnetic stirring. The samples were characterized by scanning electron microscopy, X-ray microtomography, X-ray diffraction, near-infrared spectroscopy, inductively coupled plasma emission spectroscopy, and energy-dispersive X-ray spectroscopy. The biocompatibility and ability to differentiate osteoblasts in vitro were evaluated using human cells. The incorporation of strontium into the phosphate structure was verified. Scaffolds were obtained with high porosity, three-dimensional structures, and the preferential adhesion and maturation of osteoblastic cells, which are essential to promote bone regeneration in vivo.