Comparative study of antifungal activity of silver and gold nanoparticles synthesized by facile chemical approach

Colloidal solutions of silver nanoparticles (Ag-NPs) and gold nanoparticles (Au-NPs) have been proved to be suitable antimicrobial agents. In this study, Ag-NPs (yellow color) and Au-NPs (wine red color) have been produced by chemical reduction method using silver nitrate and chloroauric acid as metal precursors with sodium borohydride as reducing agent for Ag-NPs and tannic acid as reducing agent for Au-NPs and trisodium citrate as a stabilizing agent in both cases. UV-vis spectroscopy graph shows the adsorption for Ag-NPs and Au-NPs to be 440 nm and 520 nm respectively. X-ray diffraction (XRD) analysis showed the highly crystalline nature of Ag-NPs and Au-NPs with (111), (200), (220), (311) orientations. TEM and SEM reveal the uniform spherical morphology of Ag-NPs and Au-NPs with the presence of elemental Ag and Au metal analysed by EDAX. SAD confirms the orientation of Ag-NPs and Au-NPs with XRD analysis. The average particle size of Ag-NPs and Au-NPs was found to be 25 nm and 34 nm respectively investigated by DLS. The antifungal activity of Ag-NPs and Au-NPs on fungal cells, i.e., Candida Albicans and S.Cerevesiae showed diminished fungal growth by developing inhibition zones. The comparative studies demonstrate that Ag-NPs are more active than Au-NPs in diminishing fungus.