A sensitive and selective electrochemical sensor for the simultaneous determination of trace Cd2+ and Pb2+

A neoteric sensor for the detection of Cd2+ and Pb2+ has been investigated. The sensor was investigated based on a glutathione/gold nanoparticles/amino-reduced graphene oxide (GSH/AuNPs/NH2-rGO) nanocomposite, which was decorated on a polished glassy carbon electrode. The characterization analysis of the nanocomposite was performed with scanning electron microscopy, electrochemical techniques, and FTIR. The results indicated that GSH/AuNPs/NH2-rGO/GCE exhibited excellent analytical performance in detecting Cd2+ and Pb2+ owing to its large surface area, numerous functional groups, and good electrical conductivity. Under optimized experimental conditions, the stripping peak currents were linear with the concentrations of Cd2+ and Pb2+ in the scope of 1–120 μg/L with the detection limits of 0.09 μg/L for Cd2+ and 0.38 μg/L for Pb2+ (S/N = 3). Also, the electrochemical sensor displayed excellent selectivity and reproducibility. Hence, this research revealed that GSH/AuNPs/NH2-rGO nanocomposite was a promising sensing material for the detection of Cd2+ and Pb2+.