Preparation and Antibacterial Properties of Titanium (IV) and Zinc (II) Co-doped Nanohydroxyapatite

Hydroxyapatite (Ca-10(PO4)(6)(OH)(2): HAp) nanoparticles co-doped by Ti (IV) and Zn2+ (TiZnHAp) were prepared by co-precipitation and ion-exchange method. The structure, morphology, composition, photo absorption property and catalytic activity of the samples were characterized using XRD, TEM, EDS, UV-Vis and ESR. Escherichia coli and Staphylococcu aureus were selected as testing bacterias to evaluate the bactericidal activity of the samples in darkness and under weak UV light irradiation. The results indicate that the morphology and size of the HAp crystal do not change significantly with the doping of titanium ( IV). Doping with titanium ( IV) can improve the photo absorption property and the UV catalytic activity. Compared with ZnHAp and TiHAp, TiZnHAp has very high bactericidal activity under weak UV light irradiation which can be attributed to the synergistic effect of the Ti (IV) pholocatalytic decomposition activity and the Zn2+ antibacterial activity in TiZnHAp. Ions releasing test indicates that TiZnHAp maintains long-lasting antibacterial effect.