Antibacterial Composite Layers on Ti: Role of ZnO Nanoparticles

Abstract

Problem of post-operative infections of implant materials caused by bacterial adhesion to their surfaces is very serious. Enhancement of antibacterial properties is potentially beneficial for biomaterials value. Therefore, the metallic and metallic oxide nanoparticles attract particular attention as antimicrobial factors. The aim of this work was to create nanotubular (NT) oxide layers on Ti with the addition of ZnO nanoparticles, designed for antibacterial biomedical coatings. Antimicrobial activities of titanium, TiO 2 NT and ZnO/TiO 2 NT surfaces were evaluated against bacterial strain typical for orthopaedic infections: S. epidermidis. TiO 2 NT alone killed the free bacterial cells significantly but promoted their adhesion to the surfaces. The presence of moderate amount of ZnO nanoparticles significantly reduced the S. epidermidis cells adhesion and viability of bacterial cells in contact with modified surfaces. However, higher amount of loaded nanoZnO showed the reduced antimicrobial properties than the medium amount, suggesting the overdose effect.

NanoZnO-modified titanium implants for enhanced anti-bacterial activity, osteogenesis and corrosion resistance

“…However, Roguska et al reached different conclusions when obtaining different amounts of ZnO nanoparticles by changing the electrodeposition time, and they observed that 3 min of loaded nano-ZnO was most effective in S. epidermidis killing efficacy, while more loaded nano-ZnO resulted in decreased bactericidal activity [ 54 ]. Previous studies have attributed this to a reduction in the specific surface area of modified Ti samples as well as lower solubility of aggregated nanoparticles [ 115 ]. Therefore, the content of nano-ZnO on Ti substrates should be taken into consideration.…”