Green electrochemical sensors based on boron-doped diamond and silver amalgam for sensitive voltammetric determination of herbicide metamitron

Novel sensitive voltammetric methods for determination of herbicide metamitron were developed using polished and mercury meniscus-modified silver solid amalgam electrode (p-, m-AgSAE) and boron-doped diamond electrode (BDDE). It was found that metamitron yields one analytically utilizable reduction (AgSAEs) and one oxidation (BDDE) signal. All three tested working electrodes connected to different voltammetric techniques were found to be appropriate for the analysis of the herbicide. The optimum conditions for metamitron determination were ascertained in Britton-Robinson buffer solution of pH 2.0 (m-AgSAE, BDDE) and in 0.05 mol dm(-3) H2SO4 (p-AgSAE), respectively, with the limits of detection 3.6 x 10(-8) mol dm(-3) (m-AgSAE), 1.0 x 10(-7) mol dm(-3) (p-AgSAE), and 1.2 x 10(-6) mol dm(-3) (BDDE). Calculated values of relative standard deviations of repeated determinations (n = 5) in various concentration levels of metamitron did not exceed 5 % for either of the tested electrodes. Finally, practical applicability of newly proposed methods was verified by the analysis of pesticide preparation and spiked river water.