Differential pulse voltammetry (DPV) at a glassy carbon electrode (GCE) was used for the determination of trace amounts of US EPA priority pollutant 4-nitrophenol (4NP) in Britton-Robinson buffer (BR) of pH 2.0 as an optimal base electrolyte. 4NP can be determined by DPV 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 mu mol.L-1.
The calculated limits of detection and quantification are 0.17 and 0.56 mu mol.L-1 (RSD = 2.3 % and R-2 = 0.9987 for n = 5) for cathodic reduction and 0.39 and 1.29 mu mol.L-1(RSD = 5.3 %, R-2 = 0.9928 for n = 5) for anodic oxidation.