Antibacterial Calcium Phosphate Coatings with Zinc Oxide Nanoparticles

Porous calcium phosphate coatings (C-P) with ZnO nanoparticles were obtained via the micro-arc oxidation method on a titanium substrate. ZnO nanoparticles were added to the C-P coatings to change the zeta potential and improve the coatings' bioactivity and antibacterial properties. The samples with coatings were studied via scanning electron microscopy (SEM), X-ray diffraction, energy dispersive microanalysis, potentiodynamic polarization, and zeta potential measurement. The coatings modified with ZnO nanoparticles showed improved physical, electrochemical, and electrical properties, compared to the initial unmodified coatings. Modification with ZnO nanoparticles contributed to an increase in zeta potential from -60 mV to -53 mV. Functionalization of the coatings with ZnO nanoparticles allowed us to increase the anticorrosion characteristics by about 30%. The biological studies showed that the coatings had no cytotoxic effect on L929 fibroblast cells. The antibacterial activity of the coating rose by 99% after the addition of ZnO nanoparticles against the bacterium Staphylococcus aureus.