Some remarks concerning polarographic determination of sulphur-containing herbicides

Abstract

The herbicide methomyl (2-methylthio-propionaldehyde-o-methylcarbamoyloxime) can be determined using fast scan differential pulse voltammetry with hanging mercury drop electrode by the measurement of the peak at -1.30 V (S.C.E.) which caused by the presence of methomyl in the ammoniacal buffer solution containing cobalt(II) salt. The peak current vs methomyl concentration dependence is linear over the concentration range 0.5 to 20.0 μg . l-1. The herbicide aldicarb (2-methyl-2(methylthio)propionaldehyde-o-methylcarbamoyloxime) is determined by its influence on the differential pulse voltammetric curve of copper(II) recorded in electrochemically enriched solution in acidic medium. The corresponding peak current at the potential + 0.08 V (S.C.E.) depends linearly on the aldicarb concentration in the range 0.07 to 5.00 μg ml-1.