Electrolyte effects on the surface chemistry and cellular response of anodized titanium

Anodic oxidation of titanium (Ti) material is used to enhance biocompatibility, yet the effects of various electrolytes on surface characteristics and cellular behavior have not been completely elucidated. To investigate this topic, oxide layers were produced on Ti substrates by anodizing them in aqueous electrolytes of (NH4)(2)center dot 5B(2)O(3), (NH4)(2)SO4, or (NH4)(3)PO4, after which their surface characteristics and cellular responses were examined. Overall, no surface differences between the electrolytes were visually observed. X-ray photoelectron spectroscopy (XPS) revealed that the anodized surfaces are composed of titanium dioxide (TiO2), while incorporation from electrolyte was only observed for (NH4)(3)PO4. Surface adsorption of carbon contaminants during sterilization was suppressed by anodization, leading to lower water contact angles. The attachment of MC3T3-E1 osteoblast-like cells was also improved by anodization, as evidenced by visibly enlarged pseudopods. This improved attachment performance is likely due to TiO2 formation. Overall, electrolyte selection showed no effect on either surface chemistry or cellular response of Ti materials. (C) 2015 Elsevier B.V. All rights reserved.