Simultaneous Detection of Multiple Metals in Aqueous Samples with Nanoelectrodes

Description:
Heavy metal toxicity is a rising global concern, which leads to deadly health disorders such as neurological disorders and dysfunction of kidneys and livers, creating a need to develop effective metal mitigation systems. The traditional non-electrochemical techniques employ sample pretreatment steps that alter metal speciation, a critical factor determining metal toxicity. Furthermore, most of these techniques utilize bulky instruments that are costly and tedious to operate, limiting real-time metal detection in the field. Alternatively, we pioneered developing a robust, low-cost, ultra-small, reliable electrochemical sensor to detect Cd(II) ions in environmental samples. The fundamental mechanism of our electrode is ion transfer between two immiscible electrolyte solutions (ITIES), thus eliminating the complications that can occur with electron transfer-based redox chemistry. In this study, we fabricated a dual pipet-based nanoelectrode to detect two metal ions simultaneously. We show that altering pH in the organic phase can make this double detection feasible using the difference in half-way potentials of each metal. Our new sensor can also detect multiple metal ions in artificial blood and urine samples with excellent sensitivity and stability, thus, showcasing the probability of developing this to detect ultra-low concentrations of heavy metals in vivo.

Speaker: Muzammil M.N. Ahmed - Florida Institute of Technology