Multivariate curve resolution and voltammetry. Determination of Ethiofencarb in presence of two unmodelled interferences

GOICOECHEA, H; GIBERTAU CABANILLAS; SILVA; MORA DIAZ

Barcelona

Congreso; 13 Jornadas de Analisis Instrumental; 2011

Ethiofencarb (2- ethylthiomethyl-phenyl)-N-methyl carbamate) is a systemic insecticidewidely used in agriculture acting as a cholistenarese inhibitor.The determination of Ethiofencarb by voltammetry is possible on the basis that thispesticide is hydrolysed in alkaline media given rise to a compound which shows an oxidationpeak to Ep = 0.80 V. But some other pesticides belonging to the same family can be consideredas interferences due to the high overlapping in their signals.In the present work, a method has been developed for the determination of Ethiofencarbin the presence of Fenobucarb and Bendiocarb, which have not been included in the calibrationstep. The possibility of second order multivariate calibration was study by using the hydrolysistime as the third variable and applying multivariate curve resolution. Good results wereobtained in this determination in spite of the high overlapping in voltammetric signals.