Abstract:Lead (Pb) and Cadmium (Cd) have emerged as major mussel pollutants in recent decades, thus the development of sensors capable of detecting both of Pb and Cd is of considerable interest. In this work, a bismuth film modified homemade electrode (HME) composed of ionic liquid/graphene composite (IL/GNs) was used as a working electrode for simultaneous detection of trace Pb2+ and Cd2+ in shellfish by differential pulse anodic stripping voltammetry (DPASV). The best experimental parameters were optimized and set as follows: the mass concentration of Bi3+ at 500 μg/L, the enrich time of 420 s, enrich voltage at -1.1 V, stirring speed of 600 r/min, and HAc-NaAc buffer pH at 4.2. Under the optimal conditions, the DPASV peak currents showed good linear relationships with the mass concentrations of Pb2+ and Cd2+ in the same range of 1.0~45.0 μg/L and the detection limits for Pb2+ and Cd2+ were 0.5 μg/L and 0.8 μg/L, respectively. The analysis system was successfully applied to simultaneous detection of Pb2+ and Cd2+ contents in Scallop, Ostrea plicatula, Solen gouldi, Ruditapes philippinarum, and the results were comparable with those obtained from ICP-MS. The electrochemical sensor based on IL/GNS HME is easy to be operated and has high sensitivity toward sensing Pb2+ and Cd2+. It can be used for the rapid, accurate, and simultaneous detection of trace Pb2+ and Cd2+ in shellfish.