Synthesis, characterization and evaluation of antimicrobial activity of zinc oxide nanoparticles

The study involved synthesis of Zinc Oxide nanoparticles using biological and  chemical reducing agents. The aim was to compare the yield, nature and antimicrobial activity of nanoparticles synthesized by the two methods. In biological method, hot and cold Aloe vera leaf extract; and in chemical method, sodium hydroxide was used as reducing agents. Nanoparticles synthesized by the two methods were characterized by XRD and SEM. It was evident from SEM images that particles obtained by biological method were rod-shaped and those synthesized by chemical method were spherical. Antibacterial study was carried out on gram-positive and gram-negative bacterial strains by agar-well diffusion method and their MIC values were determined. ZnO-AC showed almost consistent activity on all the strains, whereas ZnO-AH and ZnO-C showed greater activity on some strains compared to others. ZnO-AH showed least overall activity on all strains as compared to ZnO- AC and ZnO-C.Keywords: Zinc Oxide nanoparticles, biological method, XRD, SEM, antibacterial study, agar diffusion method.