Spectrophotometric determination of ziram in a commercial sample and wheat by extraction of its copper dimethyldithiocarbamate complex into molten naphthalene.

A method was developed for the determination of zinc(II) dimethyldithiocarbamate by converting it into the copper(II) dithiocarbamate complex, which is then extracted into molten naphthalene. The absorbance is measured at 430 nm versus a reagent blank. Beer's law is obeyed for concentrations of 0.63 x 10(-3) to 17.2 x 10(-3) g/L in the final solution. The method is sensitive and was applied to the determination of ziram in a commercial sample and in wheat grain.