VOLTAMMETRIC DETERMINATION OF PHOSALONE AND CARBOPHOS PESTICIDES USING A MODIFIED CARBON-PASTE ELECTRODE

A procedure for the selective determination of Phosalone and Carbophos in their alkaline hydrolyzates using a carbon-paste electrode modifie d with cobalt(II) 2,2'-dipyridylate was developed. The preconcentratio n of pesticides is based on their adsorption on the surface of the abo ve electrode with the resulting formation of electroactive mixed-ligan d Co(II) complexes. The oxidation current of the resulting mixed-ligan d chelate allows 1.2 x 10(-9) M Carbophos and 5.5 x 10(-9) M Phosalone to be detected. Dithiocarbamates, which form no mixed complexes with the modifier under the experimental conditions, cause no interference.