Microwave-assisted approach for rapid and green phytosynthesis of silver nanoparticles using aqueous onion (Allium cepa) extract and their antibacterial activity

In this paper, we report for the first time the use of onion (Allium cepa) in the biosynthesis of silver nanoparticles (AgNPs) under microwave irradiation. Influence of various reaction parameters such as microwave irradiation power and microwave irradiation time was analyzed. The synthesized nanomaterial was characterized by UV-visible absorption spectroscopy and Fourier transform infrared spectrum analysis. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirm the formation and the crystalline nature of the synthesized nanomaterial. Further, these nanoparticles were found to exhibit high antibacterial activity against two different strains of bacteria Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive).