The formation of diazonium salts by reaction of nitrite with aromatic amines is a well established process for the indirect determination of nitrite by UV/Vis spectroscopy. In this work this is adapted to an electrochemical detection process whereby the unreacted aromatic amine is determined and utilised as an indirect indicator for nitrite. The effects of the different structural isomers of sulfanilic acid and other aromatic amines as well as pH on the analytical system are reported and appraised. The results show a linear detection range of 20 μM to 80 μM for nitrite with a corresponding limit of detection of 0.7 μM. The efficacy of the approach has been shown by a 95.7% (RSD=6.4%, N=5) recovery of 4.89 μM spiked nitrite in sewage effluent.
