Antibacterial activity of ruthenium nanoparticles synthesized using Gloriosa superba L. leaf extract

This work reports an ecofriendly approach for the synthesis of Ruthenium nanoparticles (Ru NPs) using aqueous leaf extract of Gloriosa superba. G. superba contains cholidonic, superbine, colchicine, gloriosol, phy- tosterils and stigmasterin, which are found to be responsi- ble for the bio-reduction of Ru NPs. The synthesized Ru NPs were characterized using UV-Vis spectroscopy, Fluorescence spectra, FTIR, XRD, SEM and EDX analy- ses. UV-Vis spectra of the aqueous medium containing Ru NPs showed a gradual decrease of the absorbance peak observed at 494 nm. Fluorescence spectra of Ru NPs emission (kem) exhibited at 464 nm are attributed to the Ru=N p bonds transition. The biomolecules responsible for the reduction of Ru NPs were analyzed by FTIR. XRD results confirmed the presence of Ru NPs with hexagonal crystal structure. The calculated crystallite sizes using Scherrer formula are in the range from 25 to 90 nm. Scanning electron microscopy ascertained spherical nature of the Ru NPs. The EDX analysis showed the complete elemental composition of the synthesized Ru NPs. The synthesized Ru NPs exhibited good antibacterial perfor- mance against gram-positive and gram-negative bacterial strains, which was studied using standard disc diffusion method. The synthesis of Ru NPs by this method is rapid, facile and can be used for various applications.