Biosynthesis, Characterization and Antibacterial Activity of Gold Nanoparticles (Au-NPs) using Black Lemon Extract

Abstract The synthesis of gold nanoparticles (Au-NPs) have been performed by a biological method using HAuCl4, black lemon extract, and double distilled water (D.D.W). The structural analysis and average crystallite size have been investigated by XRD data and the average crystallite size came out to be 15 nm. The optical properties were recorded by UV-visible microscopy in the range of 400-800 nm. SEM and EDAX have been used to study the morphological and elemental structure of Au-NPs. The triangular and spherical shapes, verified by TEM play an important role in directing the shape evolution of nanoparticles. The diameter of inhibition zone, which was used to determine the antibacterial activities of the NPs, was obtained using the disk diffusion methods. The Au-NPs showed great ability to inhibit activities of various bacteria such as gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) by damaging their activity.