The Characterization of Zinc Oxide Films on the Surfaces of Porous Titanium Substrates and Their Antibiofilm Properties on Shewanella putrefaciens

To study the influence of the morphologies of ZnO films on its antibiofilm properties for Shewanella putrefaciens, ZnO films were prepared by hydrothermal synthesis method, which were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and water contact angle. The results showed that ZnO was hexagonal wurtzite structure, and the microstructures of ZnO films were affected by hydrothermal time. Extension of hydrothermal time, the ZnO particles were evenly stacked on the surface, and adhesion amount were increased continuously. The porous titanium film was hydrophobic, however the ZnO films exhibited hydrophilic. The attached biofilm on the ZnO films surface was increased with the incubation time. Between 0~2 h, the biofilm adhesion rate and total number of bacteria were increased rapidly, and bacteria were rapidly proliferated in the biofilm. Between 2~12 h, the biofilm adhesion rate and total number of bacteria were increased continuously, and the biofilm entered the growth phase. Between 12~36 h, the biofilm adhesion rate and total number of bacteria were held steady, and the biofilm entered mature stage. After 36 h, the biofilm adhesion rate and total number of bacteria were declined, and the biofilm entered recession period. The antibiofilm property of the ZnO film was improved due to its antibacterial property, and the longer the hydrothermal reaction time, the better the antibiofilm property was. The contribution of the bactericidal effect of ZnO films against the biofilm adhesion performance was far better than its hydrophobic properties.