ABSTRACT Fabrication of trace elements incorporated apatite coating could combine the ions’ pharmaceutical effect into the materials. In this study, strontium, silicon, and fluoride ions have been incorporated into apatite coatings through a biomineralization method, which mimics an in vitro mineralization process. The surface composition is tested with X-ray diffraction and X-ray photoelectron spectroscopy, and the surface morphology is characterized with scanning electron microscopy. Compared with pure hydroxyapatite coating, the strontium, silicon, and fluoride substituted apatite coatings show different morphology as spherical, needle-like, and nano-flake-like, individually. The crystal size of these biomimetic hydroxyapatite coatings decreased after ion substitution. The results of the analysis of surface composition present the ion substitutions are increased with the increasing of ion concentrations in the soaking solution. That means the ion incorporation into the apatite structure based on the biomineralization method could not only vary the ion content in but also change the morphology of the apatite coatings. Herein, the role of ion substitution is considered from the point of view of materials science at the micro structural and surface chemistry levels.
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