Facile one-pot synthesis of silver nanoparticles embedded alginate beads: synthesis, characterization and antimicrobial activity.

Alginate-based silver nanoparticles were prepared using a simple and efficient one-pot synthesis method and their antimicrobial activity evaluated. The prepared nanocomposites were characterised with scanning electron microscopy coupled with energy dispersive X-ray spectroscopy and powder X-ray diffraction. Morphological analysis confirmed the successful formation of the nanocomposites with well-dispersed AgNPs throughout the alginate matrix. The antimicrobial activity was evaluated using the growth inhibition zone method and batch studies. The antimicrobial results showed that the nanocomposites were effective to inhibit growth of the tested bacteria; Staphylococcus aureus (45 mm), Salmonella (44 mm) and Escherichia coli (42 mm). Batch results also showed effective inactivation of bacteria with more contact time, where no bacteria were detected in all the water samples after 8 h. Noteworthy, the ICP results showed a very slow release of Ag concentration (1.529 ppb after 24 h), which might be the reason more contact time was required for effective inactivation. After 24 h, there was still no bacteria detected in the water which shows the long performance of the nanocomposites. These results indicate that the prepared nanocomposites are promising and can effectively be utilised for water disinfection. [ABSTRACT FROM AUTHOR]