Characterization and antibacterial efficacy of silver nanoparticles extracted from neem (Azadirachta indica) leaf extract

Use of silver and silver salts is as old as human civilization but the green synthesis of silver nanoparticles (Ag NPs) has only recently been recognized. AgNPs were synthesized using aqueous extract of neem leaves and silver salt. The synthesized AgNPs were characterized using particle size analyser, UV-visible spectroscopy, XRD, SEM and AFM. The size of AgNPs was found to be within the range of 20-60 nm. The absorbance peak was in the range of 420-450 nm. SEM and AFM analysis showed that, the synthesized AgNPs are spherical in shape and surface roughness is 20.40 nm. Further the XRD analysis confirms the nano crystalline phase of silver with cubic crystal structure nature. The EDS analysis confirmed the presence of silver nanoparticles. AgNPs were specifically used in agriculture and medicine as antibacterial, antifungal and antioxidants. Antibacterial activity of synthesized AgNPs was carried out for both gram positive and gram negative bacteria and compared with standard silver nanoparticles. Hence, AgNPs could be use in the food and agricultural filed for commercial usage.