Rapid biosynthesis of novel Cu/Cr/Ni trimetallic oxide nanoparticles with antimicrobial activity

Abstract

This paper aims to synthesize for the first time environmentally benign trimetallic oxide Cu/Cr/Ni nanoparticles (NPs) using the aqueous leaf extracts of Eryngium campestre (E. campestre) and Froriepia subpinnata (F. subpinnata) as bio-reducing and capping agents. The effect of several parameters including incubation time, incubation temperature, and precursor salt to plant extract ratio was investigated in order to optimize trimetallic oxide Cu/Cr/Ni NP production. The trimetallic oxide NPs produced in their optimum condition using the two leaf extracts as well as by their 50:50 mixture and were characterized by UV–vis spectroscopy, FTIR, EDX, XRD, FESEM, and TEM analyses. The modeled experimental optimization for E. campestre leaf extract was found as time of 3 min, temperature of 34 °C and metal salt-to leaf extract ratio of 2.38 with predicted response of 73.17%. The corresponding values for F. subpinnata leaf extract including time of 3 min, temperature of 40 °C and metal salt-to leaf extract ratio of 1.07; while 72.22% conversion of metal salts into trimetallic oxide NPs was predicted by experimental design software. Antibacterial activity of the NPs was studied by determining the minimum inhibitory and bacterial concentrations on two pathogenic bacteria, namely, Gram −ve Escherichia coli PTCC1112, and Gram +ve Staphylococcus aureus PTCC1270. The results evidenced the bacterial growth inhibition effect of the trimetallic oxide NPs.