Evaluation of Antimicrobial Activity and Cytotoxicity of Biogenic Gold Nanoparticles
Author(s): K Ajith Kamath, Iffat Nasim* and S Rajesh
Gold nanoparticles are some among the most researched nanomaterials in the field of nanotechnology. They can be easily synthesised and show excellent chemical as well as thermal stability. Biosynthesized nanoparticles offer excellent biocompatibility compared to nanoparticles synthesized by any other physicochemical methods. The main objective of this study was to analyze the antimicrobial activity of the gold nanoparticles synthesised with aspartic acid and to evaluate its cytotoxicity at the embryonic level. The antimicrobial activity of the AuNPs was assessed by the well diffusion method using different clinical pathogenic bacteria namely, E faecalis, S.mutans, Pseudomonas, and S. aureus. Zebrafish were selected for this study to analyze the cytotoxicity of the AuNPs. The zone of inhibition was seen to be the largest in E. faecalis(20mm) and smallest in S.aureus (9mm). When compared to the control antibiotics, Ampicillin (1mg/ml), the zone of inhibition was larger in the S mutans (18mm) at 100μg/mL followed by Pseudomonas (12mm zone) at100μg/mL. It was seen that mortality rate proportionally increased as the concentration of the solution of AuNPs increased. The AuNPs showed considerable antimicrobial property when tested against various pathogenic strains of bacteria. The AuNPs however showed to be dose dependent cytotoxic in nature. More studies need to be undertaken to establish optimum concentrations of AuNPs to have minimum negative effects on the host and best deliver its therapeutic purpose.