A New Differential Pulse Anodic Stripping Voltammetry Miniaturized Sensor System for Detection of Nickel and Mercury in Waters

In this work, a new miniaturized system was developed for nickel and mercury detection with differential pulse anodic stripping voltammetry measurements (DPASV). The miniaturized system consists of a screen-printed microelectrode chip, a carbon working microelectrode (empty set 1 mm), an integrated Ag/AgCl reference electrode, a platinum counter electrode, and a 20 mu L PMMA microcell. The measurements with this miniaturized system were compared to measurements performed in a classical system with a glassy carbon electrode (0 3 mm). The results show that the miniaturization of the system (volume decreased by a factor of 1000 and diameter of the electrode by a factor of 3) presents several advantages: sensitivity for metal detection increased by a factor of 10 compared to a classical measuring system. The detection and quantification of Ni (II) and Hg (II) were statically performed using differential pulse anodic stripping voltammetry in the microsystem. In the Ni (II) concentration range of 0.5-550 ppb, a limit of detection of 0.15 ppb and a sensitivity of 1.489 nA/ppb are obtained. In the Hg (II) concentration range of 0.1-350 ppb, a limit of detection of 0.03 ppb and a sensitivity of 0.097 nA/ppb is obtained.