Spectrophotometric determination of some insecticides with 3-methyl-2-benzothiazolinone hydrazone hydrochloride.

A simple, rapid and sensitive spectrophotometric method is described for determining carbaryl, propoxur, fenitrothion and methyl parathion, based on reaction of their hydrolysis or reduction products (as appropriate) with 3-methyl-2-benzothiazolinone hydrazone hydrochloride in the presence of an oxidant (Ce(4+) or Fe(3+)) to give coloured species.