Document Type: Research Paper
Department of Chemical Engineering, College of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran.
Department of Food Science, Sarab Branch, Islamic Azad University, Sarab, Iran.
The aim of this study was to synthesize Ag-nanoclay composite by solid ion exchange, then characterize, and evaluate the antibacterial activity. This newly introduced ion exchange is a simple and low cost technique, which provides a quicker method. Without chemical treatment, nanoclay was subjected to an ion exchange process in media containing molten salt of silver at 300 and 400 °C and at different periods. Scanning electron microscopy showed that the flakes’ structure was opened by higher temperature and longer time. DRS graph revealed that Ag particles were successfully loaded, and that higher temperature and longer time increased the loading amount. Changes in basal reflection in XRD peak validated the presence of Ag. The Release test indicate that the materials do not present any risk for drinking water treatment since the leached metals were very small and in acceptable concentrations. The constant amount of release after four hours of sharp releasing. The antibacterial activity of the prepared composites was tested against gram-negative Escherichia coli and Staphylococcus aureus using the disc diffusion method. Presence of an inhibition zone clearly indicates the antibacterial effect of the composites. The results demonstrate that silver can be introduced onto nanoclay by single-step ion exchange.