A promising hydroxyapatite whisker with long-term and high-efficiency antibacterial performance and its potential application in implant

Abstract

• The synergistic effect of nano-zinc oxide and silver ions can realize broad-spectrum antibacterial. • The silver ions in the hydroxyapatite whiskers will gradually dissolve as the whiskers degrade, realizing long-term antibacterial effects. Osteomyelitis remains one of the most challenging diseases for orthopedic doctors despite the advancement of therapeutic techniques. Biomaterials with antibacterial activities are beneficial to prevent infection post implantation. The aim of this study was to evaluate the antibacterial effects of three biomaterials including pure- hydroxyapatite (HA), Ag-HA and Ag-HA/ZnO. The prepared materials were analyzed by X-ray diffractometer (XRD), scanning electron microscope (SEM), cell adhesion and long-service antibacterial ability. The results showed that with the increase of silver content, the growth of whiskers was inhibited and the aspect ratio became smaller. Nano-zinc oxide is evenly attached on the surface of the whiskers. Escherichia coli ( E. coli) and Staphylococcus aureus ( S. aureus) were used for antibacterial tests. The results showed that Ag-HA and Ag-HA/ZnO had good antibacterial ability against E. coli and S. aureus . Thus, the low amount of Ag-HA has a potential of minimizing the risk of bacterial contamination, without compromising the bioactivity, and is expected to display greater biological efficacy in terms of osseointegration. Ag + and ZnO particles have a synergistic effect and can effectively kill most bacteria. At the same time, with the degradation of hydroxyapatite, Ag + is slowly released, which can play a long-term antibacterial effect.