Biological adhesion and electrochemical behavior of Ag-ZrO2 bioceramic coatings for biomedical applications

Recently, surface tailoring of the metallic implant has taken considerable attention to enhance the longevity of implants. In this study, two different concentrations of silver (Ag) with zirconia (ZrO2) were deposited onto titanium (Ti) substrates using DC magnetron sputtering for both orthopedic and dental implants application. Thickness, surface morphology with elemental composition, functional group, and adhesion of the coatings were characterized by X-ray diffraction (XRD), stylus profilometer, field-emission scanning electron microscopy/energy-dispersive X-ray spectroscopy (FESEM/EDAX), Fourier transform infrared spectroscopy (FTIR) and nano-scratch indentor, respectively. Monoclinic phase of ZrO2 and cubic phase of Ag were confirmed with XRD. Nanostructured grains were obtained by FESEM analysis with the thickness of similar to 300 nm, similar to 700 nm and similar to 800 nm for ZrO2, ZrO2-Ag and ZrO2-Ag(1) (Herein, ZrO2-Ag (low conc.) and ZrO2-Ag(1) (high conc.) coatings measured by profilometer. The in vitro bacterial adhesion was performed for as prepared ZrO2, ZrO2-Ag and ZrO2-Ag(1) coatings against E.coli, and Streptococcus sp. Adhesion study exhibits better performance for Ag containing ZrO2 rather than ZrO2 coated and uncoated Ti. Adhesion of platelet on the coated and uncoated Ti revealed that activated platelets are present in ZrO2-Ag(1) coated Ti. ZrO2 and ZrO2-Ag coated Ti showed enhanced fibroblast cell attachment and proliferation than uncoated Ti but not in ZrO2-Ag(1) coated Ti surface. Electrochemical impedance spectroscopy (EIS) results revealed superior corrosion resistance behavior for all the coatings than uncoated Ti in ABP electrolyte. The results stated those tailored Ti surfaces were certainly used to enhance the durability of the implant for biomedical applications.