*Dorina Mihut, Arash Afshar, Laura Lackey, Stephen Hill, Khang Le, David Carter, Mercer University, Atlanta, GA
The research is investigating the combined antibacterial effects obtained by using silver thin films on water filter papers in conjunction with low DC electrical powers applied to metallic coated structures for wastewater treatment. It is also investigating the antibacterial effect of ultrasonic agitation of silver coated structures. High vacuum magnetron sputtering technique was used to deposit silver thin films on water filter papers and the resulted structures were conductive. The morphology, distribution and adherence of metallic thin films to filter fibers were examined using digital optical microscopy and Scanning Electron Microscopy (SEM). The coated structures were effectively acting against common types of wastewater bacteria (e.g. Escherichia coli and other coliforms). The water containing bacteria samples was collected from local basins and the antibacterial effects were characterized using the standardized membrane filtering technique for water examination. Wastewater was tested for the bacterial content before and after the exposure to uncoated, metallic coated filter fibers, and to electrically activated coated filter fibers. Higher antibacterial effects resulted by applying electricity to the metalized fibers and increasing the electrical power enhanced the antibacterial performance. Accordingly, shorter exposure times were required to deactivate bacteria from the contaminated water. Higher antibacterial effects were also obtained for ultrasonically agitated silver coated structures.