International Journal of Current Microbiology and Applied Sciences
ISSN: 2319-7706 Volume 2 Number 4 (2013) pp. 20-30
The Antibacterial Activity of Activated Carbon, Silver, Silver Impregnated Activated Carbon and Silica Sand Nanoparticles against Pathogenic E. coli BL21
M.Karnib1 , H.Holail1 , Z.Olama1 , A.Kabbani2 and M.Hines3 
1Department of Biological and Environmental Sciences, Faculty of Science, Beirut Arab University, Lebanon. 2School of Arts and Sciences, Department of Chemistry, Lebanese American University, Lebanon. 3College of Sciences, Department of Biological Sciences, University of Massachusetts Lowell, U.S.A. *Corresponding author e-mail: 
The ability of the activated carbon, silver impregnated activated carbon, and silica sand to eliminate and destroy water borne E. coli BL21 were tested under plate assay and shake flask technique. Silver nanoparticles showed the highest antibacterial effect against E. coli BL21 with inhibition zone diameter 18 mm, on using the shake flask technique it was proved that bacterial count started to be reduced after one hour of incubation, while no bacterial growth was detected after 2,3 and 24 hours using the activated carbon. Bacterial growth was completely inhibited on using silver impregnated activated carbon at all the tested concentrations after one hour of incubation.
Antibacterial activity; activated carbon; silver nanoparticles; silica sand; E. coli BL21.