Structural and antibacterial properties of doped zinc oxide and their composites with hydroxyapatite

ZnO nanoparticles (NPs) doped by Mn2+ and Cu2+ ions at various doping levels and their hydroxyapatite (HA) composites are prepared by a facile hydrothermal and sol-gel method. The resultant doped ZnO NPs are of wurtzite crystal structure and nanorod morphology. The doping of transition metals in ZnO lattice structure offers feasible means to prepare effective antibacterial agent. The antibacterial property against gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus) shows that both Mn and Cu-doped ZnO NPs are more sensitive to S. aureus and revealed improved antimicrobial activity relative to pristine ZnO. 5% Mn and 10% Cu-doped ZnO NPs exhibited the best antibacterial property. Moreover, the composites by loading 10 wt% Mn-doped ZnO and 10 wt% Cu-doped ZnO on HA exhibit significant antibacterial activity. The CCK-8 experiments show that ZnO/HA composites are noncytotoxic and can promote osteosarcoma cell growth.

Automated summary

ZnO nanoparticles doped with Mn2+ and Cu2+ ions show promising antibacterial properties, especially against gram-positive bacteria. The composites of Mn and Cu-doped ZnO loaded on hydroxyapatite exhibit significant antibacterial activity and are noncytotoxic.