Layered titanates with fibrous nanotopographic features as reservoir for bioactive ions to enhance osteogenesis

摘要

Graphical abstractDisplay OmittedHighlights•Higher pH conditions enhance the loading efficiency of bioactive ions in titanates.•Bioactive ions release doesn’t compromise the structural integrity of the surface layer.•Bioactive ions together with nanotopographic features enhanced the osteogenic activity.AbstractIn this study, an osteogenic environment was constructed on Ti alloy implants byin-situformation of nanosized fibrous titanate, Na2Ti6O13, loaded with bioactive ions, i.e. Sr, Mg and Zn, to enhance surface bioactivity. The bioactive ions were loaded by ion exchange with sodium located at inter-layer positions between the TiO6slabs, and their release was not associated with the degradation of the structural unit of the titanate.In-vitrocell culture experiments using MC3T3-E1 cells proved that both bioactive ions and nanotopographic features are critical in promoting osteogenic differentiation of the cells. It was found that the osteogenic functions of the titanate can be modulated by the type and amount of ions incorporated. This study points out that nanosized fibrous titanate formed on the Ti alloy can be a promising reservoir for bioactive ions. The major advantage of this approach over other alternatives for bioactive ion delivery using degradable bioceramic coatings is its capacity of maintaining the structural integrity of the coating and thus avoiding structural deterioration and potential mechanical failure.