Differential pulse voltammetric determination of 4-nitroaniline using a glassy carbon electrode: comparative study between cathodic and anodic quantification

Differential pulse voltammetry with a glassy carbon electrode was used for the determination of trace amounts of 4-nitroaniline in Britton-Robinson buffer at pH 2.0 as an optimal base electrolyte. 4-Nitroaniline can be determined by differential pulse voltammetry directly using either its electrochemical oxidation or reduction. The calibration curve was measured for both reactions in the same concentration range from 2 to 100 μmol dm−3. The calculated limits of detection and quantification are 0.2 and 0.7 μmol dm−3 (RSD 6.62 % and R 2 = 0.9906 for n = 5) for cathodic reduction and 0.3 and 1.0 μmol dm−3 (RSD 7.62 % and R 2 = 0.9995 for n = 5) for anodic oxidation.