Use of differentiation and smoothing in linear-sweep and staircase stripping voltammetry of some metals

Two methods of signal smoothing were considered: square-wave (moving average) and triangular (weighted average) filters. It was found that smoothing by these two filters did not distort noticeably the signal shape and the linearity of calibration plots. Calibration plots for several series of analytical signals of heavy metals were studied. Analytical signals were obtained by stripping voltammetry using a mercury thin-film electrode and processed using the peak area, the peak height, and the range of the extrema of the first and second peak derivatives. It was shown that, for staircase stripping voltammetry, the linearity of calibration plots decreases substantially in this series of signal processing methods. For linear sweep, calibration plots were linear over the entire concentration range for all signal-processing methods.