Hindrance of Osteoblast Cell Adhesion on Titanium by Surface Nanostructuring

The surfaces of Ti Grade 2 plates were covered with glancing angle deposited (GLAD) Ti nanorods, which were subsequently anodized. The anodization step had an impact on the morphology and composition of the Ti GLAD nanorods, as revealed by transmission electron microscopy. Atomic force microscopy measurements have shown a decreased roughness after the anodization of GLAD nanorod-covered Ti samples. This directly impacted the surface wettability, which changed from hydrophilic to hydrophobic upon anodization, as contact angle measurements revealed. Furthermore, the coulometrically determined electrochemically active surface area of the Ti GLAD samples was 7 times larger than the one of a polished Ti sample with the same projected area, used as a reference. The surfaces of the samples were electrochemically characterized and the corrosion properties were determined. Overall, the Ti GLAD samples immediately after deposition have presented superior corrosion resistance as compared to the polished Ti sample. The additionally anodized sample showed a stronger improvement compared to the non-anodized version. Electrochemical impedance spectroscopy measurements were done to further study the oxide properties, and the data were fitted to the proposed electrical circuit models. Finally, the bioassessment with Saos-2 cells showed osseo-repellent properties for Ti GLAD samples.