Original scientific paper

Electrochemical Study of the Pesticide Methidathion at a Mercury Electrode under Cathodic Stripping Mode

Valentin Mirčeski ; Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University in Skopje,vP. O. Box 162, 1000 Skopje, Republic of Macedonia
Dariusz Guziejewski ; Department of Instrumental Analysis, University of Łódź, Pomorska 163, 90-236 Łódź, Poland
Sławomira Skrzypek ; Department of Instrumental Analysis, University of Łódź, Pomorska 163, 90-236 Łódź, Poland
Witold Ciesielski ; Department of Instrumental Analysis, University of Łódź, Pomorska 163, 90-236 Łódź, Poland

Abstract

Methidathion, a non-systemic organophosphorous insecticide and acaricide is studied at
the hanging mercury drop electrode under cathodic stripping mode by means of cyclic and square-wave
voltammetry (SWV). Its electrode reaction is analyzed in the light of recent theory of cathodic stripping
processes of insoluble salts of SWV. Its complex electrode mechanism is described by an electrode
reaction of a second order, complicated by adsorption of methidathion molecules on the electrode surface
involving lateral interactions between each other. Moreover, under specific experimental conditions
the electrode mechanism can be additionally complicated by multilayer formation on the electrode
surface, as well as by a chemical transformation following the cathodic stripping process of the methidathion-
mercury salt. Following the mechanistic study of the electrode reaction, a method for quantitative
determination of methidathion is proposed applying SWV.

Keywords

methidathion; cathodic stripping; square-wave voltammetry

Hrčak ID:

56012

URI

https://hrcak.srce.hr/56012

Publication date:

15.7.2010.

Visits: 1.998 *