Determination of trace Se(IV) by anodic stripping voltammetry following double deposition and stripping steps

A procedure of Se(IV) determination by anodic stripping voltammetry using two deposition and stripping steps at gold electrodes was proposed. A well-defined stripping peak of selenium was obtained at potential 0.9 V. The optimization of parameters influencing the selenium peak current including both deposition and stripping steps was performed. A linear relationship was observed between the Se(IV) peak current and its concentration in the range from 5×10^-9 to 1×10^-7mol L^-1. The limit of detection was found to be 8.5×10^-10mol L^-1. Repeatability of the method determined as RSD % for Se(IV) concentration of 5×10^-8mol L^-1 was 4.3% (n=7). The proposed procedure was used for Se(IV) determination in certified reference material and natural water samples and acceptable results and recoveries were obtained.