Xanthan Gum-Mediated Silver Nanoparticles for Ultrasensitive Electrochemical Detection of Hg2+ Ions from Water

An environmentally safe, efficient, and economical microwave-assisted technique was selected for the production of silver nanoparticles (AgNPs). To prepare uniformly disseminated AgNPs, xanthan gum (XG) was utilized as both a reducing and capping agent. UV-Vis spectroscopy was used to characterize the formed XG-AgNPs, with the absorption band regulated at 414 nm under optimized parameters. Atomic force microscopy was used to reveal the size and shape of XG-AgNPs. The interactions between the XG capping agent and AgNPs observed using Fourier transform infrared spectroscopy. The XG-AgNPs were placed in between glassy carbon electrode and Nafion (R) surfaces and then deployed as sensors for voltammetric evaluation of mercury ions (Hg2+) using square-wave voltammetry as an analytical mode. Required Nafion (R) quantities, electrode behavior, electrolyte characteristics, pH, initial potentials, accumulation potentials, and accumulation durations were all comprehensively investigated. In addition, an electrochemical mechanism for the oxidation of Hg2+ was postulated. With an exceptional limit of detection of 0.18 ppb and an R-2 value of 0.981, the sensors' measured linear response range was 0.0007-0.002 mu M Hg2+. Hg2+ evaluations were ultimately unaffected by the presence of many coexisting metal ions (Cd2+, Pb2+, Cr2O4, Co2+,Cu2+, CuSO4). Spiked water samples were tested using the described approach, with Hg2+ recoveries ranging from 97% to 100%.

Automated summary

An environmentally safe and efficient technique using microwave-assisted synthesis of silver nanoparticles (AgNPs) was developed. Xanthan gum (XG) was used as both a reducing and capping agent for the uniform synthesis of AgNPs. The synthesized XG-AgNPs were characterized using UV-Vis spectroscopy, atomic force microscopy, and Fourier transform infrared spectroscopy. These XG-AgNPs were successfully used as sensors for the voltammetric evaluation of mercury ions (Hg2+), showing excellent detection limits and linear response range. The proposed method also demonstrated good selectivity for Hg2+ detection in the presence of other metal ions.