Characterization and investigation of electrochemical and biological properties of antibacterial silver nanoparticle-deposited TiO2 nanotube array surfaces.

The one of main reasons of the premature failure of Ti-based implants is infections. The metal- and metal oxide-based nanoparticles have very high potential on controlling of infections. In this work, the randomly distributed AgNPs-deposited onto well-ordered TiO2 nanotube surfaces were fabricated on titanium by anodic oxidation (AO) and electrochemical deposition (ED) processes. AgNPs-deposited nanotube surfaces, which is beneficial for bone tissue growth exhibited hydrophilic behaviors. Moreover, the AgNPs-deposited nanotube surfaces, which prevent the leaching of metallic Ti ions from the implant surface, indicated great corrosion resistance under SBF conditions. The electrochemical corrosion resistance of AgNPs-deposited nanotube surfaces was improved up to about 145% compared to bare Gr2 surface. The cell viability of AgNPs-deposited nanotube surfaces was improved. Importantly, the AgNPs-deposited nanotube surfaces exhibited antibacterial activity for Gram-positive and Gram-negative bacteria. Eventually, it can be concluded that the AgNPs-deposited nanotube surfaces possess high stability for long-term usage of implant applications.

Surface characterization, electrochemical properties and in vitro biological properties of Zn-deposited TiO2 nanotube surfaces.

In this work, to improve antibacterial, biocompatible and bioactive properties of commercial pure titanium (cp-Ti) for implant applications, the Zn-deposited nanotube surfaces were fabricated on cp-Ti by using combined anodic oxidation (AO) and physical vapor deposition (PVD-TE) methods. Homogenous elemental distributions were observed through all surfaces. Moreover, Zn-deposited surfaces exhibited hydrophobic character while bare Ti surfaces were hydrophilic. Due to the biodegradable behavior of Zn on the nanotube surface, Zn-deposited nanotube surfaces showed higher corrosion current density than bare cp-Ti surface in SBF conditions as expected. In vitro biological properties such as cell viability, ALP activity, protein adsorption, hemolytic activity and antibacterial activity for Gram-positive and Gram-negative bacteria of all surfaces were investigated in detail. Cell viability, ALP activity and antibacterial properties of Zn-deposited nanotube surfaces were significantly improved with respect to bare cp-Ti. Moreover, hemolytic activity and protein adsorption of Zn-deposited nanotube surfaces were decreased. According to these results; a bioactive, biocompatible and antibacterial Zn-deposited nanotube surfaces produced on cp-Ti by using combined AO and PVD techniques can have potential for orthopedic and dental implant applications.