Study of selective sensing of Hg2+ ions by green synthesized silver nanoparticles suppressing the effect of Fe3+ ions

Abstract In this present study, we eliminate the strong interference effect of Fe 3+ ions commonly observed in silver nanoparticles (AgNPs) based selective detection of toxic metal ions by localized surface plasmon resonances (LSPRs) of AgNPs. The photoinduced green crystalline silver nanoparticles (NPs) are synthesized using Allium sativum (garlic) extract. The bio ligands act as reducing as well as stabilizing agents and presence of ambient light source enhances the process of nanoparticles formations. The nanoparticles are well characterized by different measurement techniques (UV–vis, DLS-zeta sizer, XRD, TEM). The average particle size as calculated from TEM histogram study was found to be around 10 nm. The as synthesized nanoparticles are employed for selective and sensitive detection of Hg 2+ showing excellent sensitivity with a lower detection limit of 2 μM. Fe 3+ ions are also capable of oxidizing metallic Ag nanoparticles into ionic Ag + in water medium and we are able to sense Fe 3+ ions are by this green synthesized AgNPs. But the etching of Ag + ions from AgNPs by Fe 3+ ions are extremely quenched by the components of phosphate buffer medium. So the phosphate buffer medium provides good environment around AgNPs for selective and sensitive sensing of Hg 2+ ions by lowering the localized surface plasmon resonances.