Exploring bimetallic Au–Ag core shell nanoparticles reduced using leaf extract of Ocimum tenuiflorum as a potential antibacterial and nanocatalytic agent

Abstract

Biosynthesis of bimetallic Au-Ag core shell nanoparticle under ambient condition using Ocimum tenui orum (Krishna Tulsi) leaf extract is being reported for the rst time. For the biosynthesized bimetallic core shell nanoparticles (OTAuAgNPs) visual and spectrophotometric analysis was performed.Development of a deep purple color suggested the creation of OTAuAgNPs. It was then validated by UV-Vis spectrophotometry within 4 hours of incubation showing a surface plasmon resonance peak at 560 nm. FESEM-EDAX, FT-IR, particle analyzer and XRD were the analytical techniques employed to characterize the biosynthesized OTAuAgNPs. Using a known antibiotic as a control, OTAuAgNPs had a substantial bacteriostatic effect against Gram +ve (Bacillus subtilis) and Gram -ve (E.coli, Pseudomonas aeruginosa) bacteria. The OTAuAgNPs showed good catalytic action for the adsorption of Coomassie brilliant blue R250 dye (CBB), con rmed by the reduction in absorbance maxima that is time dependant.A remarkable adsorption of CBB (94.79%) was attained within 120 min, and the results were best suited PSO and Elovich models with adsorption kinetic constant of 5.96E −04 g/mg.min and 37.81mg/g.min respectively. Further the toxicity studies of brilliant blue R250 dye and metabolite of CBB (post nanoremediated dye solution) was carried out on Vigna radiata (green gram) germination and growth. OTAuAgNPs as nano catalyst remediated water revealed that it was nontoxic. Thus an ecofriendly and cost effective approach for bimetallic nanoparticle synthesis could be further explored for removal of CBB from wastewater e uents.

Electrochemical detection and removal of brilliant blue dye via photocatalytic degradation and adsorption using phyto-synthesized nanoparticles

“…17 S. Nayak et al demonstrated 94.79% adsorption of the dye by using Au–Ag core shell nanoparticles. 18 ZnO is a widely used photocatalyst owing to its tunable band gap. Copper doping to the ZnO lattice can significantly reduce the band gap, as well as minimize the rate of charge recombination.…”