Cu/HA/ZnS/PEEK multicomponent coatings with varied copper content for biomedical applications

In this study, multicomponent Cu/HA/ZnS/PEEK coatings were electrophoretically deposited (EPD) on Zr-2.5Nb alloy substrates. The kinetics of coating deposition from suspensions with various Cu contents was studied. Heating and slow cooling enabled the densification of coatings. The densified coatings were characterized by a limited number of pores and the presence of HA agglomerates on their surface. All of the obtained coatings exhibited significant roughness and mild hydrophilicity, as well as high adhesion to the alloy substrates. The coatings increased the electrochemical corrosion resistance of the zirconium alloy. The coating obtained from the suspension with the highest copper content exhibited high antibacterial properties for both bacteria strains after 24 h. However, after 72 h incubation, the samples had a better effect against Gram-negative than Gram-positive bacteria. Furthermore, this coating variant allowed the formation of hydroxyapatite on its surface in the Kokubo test. The obtained coatings showed antibacterial and bioactive properties with potential for further development, particularly as permanent coatings for bone implant applications.