Adsorptive stripping voltammetric determination of the herbicides atrazine and ametryne

Abstract

The optimum conditions were established for the determination of the herbicides atrazine and ametryne by differential-pulse voltammetry at a hanging mercury drop electrode in the concentration range from 1×10-5 to 1×10-7 mol dm-3 using a supporting electrolyte at pH 3.0. The sensitivity of the determination can be improved through adsorptive accumulation of the investigated substances on the surface of the hanging mercury drop electrode: differential-pulse adsoprtive stripping voltammetry enables the determination of atrazine (at pH 3.0) and ametryne (at pH 3.0 and 5.0) in the concentration range from 1×10-7 to 1×10-9 mol dm-3. The method described is selective: the herbicides under study can be determined in their mixture according to the dependence of the peak current on pH. The procedure was applied to the selective determination of atrazine and ametryne in various standard solutions, with results of satisfactory accuracy and precision. Recoveries were 97.5-105%.