Development of Metallic Nano Systems Gold and Silver for Anti Microbial and Sensing Applications

Abstract

Metal nanoparticles (M-NPs) have captivated the interest of the scientific community in the realm of contemporary nanotechnology since their discovery by Faraday in 1857. Because of its remarkable features, it has attracted a lot of attention. The surface qualities such as greater surface area to volume ratio, surface charge, shape, size, crystallinity, and reactivity are some of the functional aspects of M-NPs. These properties enable them for applications in the field such as biosensors, imaging, drug delivery systems, conformational studies of biomolecules, cosmetics, foods, feeds, mechanics, electronics, energy devices, and medicinal applications. Considering above mentioned features of M-NPs in mind, current study aimed to develop gold nanoparticles using gentamicin through one-pot synthesis for antimicrobial applications. Furthermore, we also have tried to develop silver nanoparticles employing quercetin as reducing and stabilizing agent for sensing application. One-pot synthesis of gold nanoparticles (G-AuNPs) was achieved by reacting gentamicin of 0.1 mM concentration with auric chloride of 2.5 mM concentration in 1:1 ratio. The optimum pH for the synthesis was 10 while optimum temperature for synthesis was 55 °C. UV-vis spectroscopy confirmed the synthesis of G-AuNPs and exhibited absorption maximum at 520 nm. Transmission electron microscopy (TEM) revealed that G-AuNPs were 13±3 nm in size with spherical in shape. The hydrodynamic size of G-AuNPs was found to be 15±3 nm by dynamic light scattering analysis (DLS). The synthesized G-AuNPs were found to exhibit synergistic antibacterial activity. The zone of inhibitions by G-AuNPs against E. coli ATCC 25922, E. fergusonii ATCC 35469, E. coli DH5and#945;, and S. aureus MTCC 3160 were 15 mm, 14 mm, 11 mm, and 11 mm (pgt0.05) respectively. The G-AuNPs were observed to had MIC of 0.01 nM, 0.046 nM, 0.0046 nM, and 0.0046 nM (pgt0.05) towards E. coli ATCC 25922, E. fergusonii ATCC 35469, E. coli DH5and#945;, and S. aureus MTCC 3160, respectively. E. coli DH5and#945;, E. coli ATCC 259