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New and Sensitive Electroquantification of Sulfentrazone in Soil by Differential-Pulse Voltammetry

In this work, a new and sensitive electroanalytical methodology was developed and validated to quantify sulfentrazone in soil samples. Sulfentrazone was initially characterized qualitatively using cyclic voltammetry (CV). Its oxidation occurred by diffusion (mass transport) on a glassy carbon electrode (GCE) via irreversible transfer of one electron close to a peak potential of +0.936 V vs. Ag|AgCl, 3.0 mol L-1 KCl, in 0.10 mol L-1 KOH. Differential-pulse voltammetry (DPV) was the most sensitive and selective technique, with limits of detection (LOD) of 1.94 and 2.19 mmol L-1 and limits of quantification (LOQ) of 6.46 and 7.31 mmol L-1, in the absence and presence of soil matrix, respectively. The reproducibility of the method ranged between 2.65 and 4.2%, with intermediate precision between 5.32 and 10.9%. The recovery rate ranged between 88.5 and 103%. Additionally, the accuracy of the electroanalytical method was validated by comparing the results with data from a standard analytical methodology of high-performance liquid chromatography (HPLC/UV-Vis).

Keywords:
voltammetry; sulfentrazone; glassy carbon electrode; differential-pulse voltammetry


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