Antibacterial activity and intracellular accumulation of silver nanoparticles on Escherichia coli K-12

Y.J. Choi, B.-T. Lee, K.-W. Kim, K.H. Chung, W.K. Song
Gwangju Institute of Science and Technology, KR

Keywords: antibacterial activity, accumulation, silver nanoparticle, Escherichia coli K-12

Summary:

We exposed Escherichia coli K-12 to engineered silver nanoparticles (AgNPs) on to understand the antibacterial activities of AgNPs. Optical density measurement by UV-Vis was used to determine the growth inhibition of AgNPs and silver ions. Exposure to 10 mg AgNP/L as total Ag concentration showed the significant delay of lag phase. E. coli K-12 did not grow up when exposed to 30 mg AgNP/L as total Ag concentration. Silver nitrate was more toxic than AgNPs if they were compared as total Ag concentration. Transmission electron microscopy (TEM) was used to observe cell morphological changes and intracellular accumulation of AgNPs. AgNPs were found to interact with cell surface and significant amount of AgNPs were accumulated in E.coli K-12.