Fabrication and properties of biodegradable ZnO nano-rods/porous Zn scaffolds

Biodegradable ZnO nano-rods/porous Zn scaffolds were successfully fabricated by treating the porous Zn scaffolds in NaCl solution at 80 degrees C. X-ray diffraction (XRD) analysis shows that the nano-rods in situ fabricated on the porous Zn scaffolds in NaCl solution are hexagonal ZnO phase. This result is also confirmed by the image of high resolution transmission electron microscope (HRTEM) and the analysis of X-ray photoelectron spectroscopy (XPS). Compressive tests suggest that the compressive mechanical properties of the ZnO nano-rods/porous zinc scaffolds do not decrease significantly compared with that of the porous Zn scaffolds without treating in NaCl solution. Immersion tests in simulated body fluid (SBF) show that the ZnO nano-rods/porous zinc scaffolds slightly gain in weight after 16 days of immersion. Moreover, these ZnO nano-rods/porous zinc scaffolds can efficiently induce Ca-P precipitation during immersion tests and show a good bioactivity. In addition, antibacterial tests imply that the ZnO nano-rods/porous zinc scaffolds have an excellent antibacterial ability against Escherichia coli and Staphylococcus aureus. However, the results of cytotoxicity tests of ZnO nano-rods/porous Zn scaffolds are not satisfactory.