Voltammetric study on the complex of thiram–copper(II) and its application

Abstract

Based on the formation of tetramethylthiuram disulfide (thiram)–copper(II) complex by square-wave voltammetry on a glassy carbon electrode, a new method is proposed for determination of thiram. There is a good linear relationship between peak current and concentration of thiram in the range of 6.0×10 −6 to 8.0×10 −5 mol l −1 ( r=0.999). The method is applied to the determination of thiram residue in plant with satisfactory results, compared with results achieved by using HPLC. Two oxidation peaks and two reduction peaks are obtained by cyclic voltammetry on a glassy carbon electrode in 0.2 mol l −1 HAc–NaAc (pH 4.0) solution containing thiram–copper(II) complex. The electrode reaction process is quasi-reversible with adsorptive characteristics. The mechanism of electrode reaction is discussed.