THE DETERMINATION OF 4-SUBSTITUTED DERIVATIVES OF N-NITROSO-N-METHYL ANILINE BY FAST SCAN DIFFERENTIAL PULSE VOLTAMMETRY AT A HANGING MERCURY DROP ELECTRODE .18.

Optimum conditions were found for the determination of N-nitroso-N-methyl aniline and its derivatives substituted in the 4 position by -CH3, -OCH3, -Cl, -CN, -OH or -NO2 groups by fast scan differential pulse voltammetry at a hanging mercury drop electrode in the concentration range 1 . 10(-5)-2. 10(-7) mol l-1. It was demonstrated that these techniques are useful for the analysis of a mixture of the test substances either directly or after separation by thin-layer chromatography and that false positive results can be eliminated by UV irradiation of the test sample. An attempt to further increase the sensitivity by adsorptive accumulation of the test substances on the surface of the hanging mercury drop electrode was not successful as the test N-nitroso compounds are practically not adsorbed on this electrode.