Synthesis and antimicrobial properties of nanosilver

Nanosilver (nAg) was prepared via Tollens method using dextrin as stabilizer. The morphology, size distribution and average size of the obtained nAg were characterized using Transmission electron microscope (TEM) and Dynamic light scattering (DLS) technique. A kinetic study of toxicity of nAg on Escherichia coli (E. coli) was determined. The obtained results showed that nAg exhibits spheric shape with an average particle size of 14 nm. The average particle size of nAg increased with increasing concentration of the salt in the solutions. The toxicity of nAg in DI water increased with increasing nAg concentration. A dose-response relation between E. coli and different concentrations of nAg was found. Solutions containing divalent cations solutions could promote the aggregation of nAg. In addition, the toxicity assay indicates that small nAg were more toxic than larger nAg aggregates (nAg concentration: 0.1 mM)