First Order Derivative of Differential Pulse Voltammetry for the Selective and Sensitive 4‐Nitrophenol Determination in the Presence of 2‐Nitrophenol at a Bare Graphite Electrode

Abstract

Derivative processing of the signal obtained by differential pulse voltammetry was applied in this work as a simple strategy to achieve the sensitive and selective 4‐nitrophenol (4‐NP) determination in the presence of the interfering compound 2‐nitrophenol (2‐NP). The derivative voltammogram displayed a well‐defined and fully separated 4‐nitrophenol anodic peak, which was used for its quantification in two linear concentration ranges extended up to 10 μmol L⁻¹ and up to 100 μmol L⁻¹. A LOD as low as 0.1 μmol L⁻¹ (S/N=3) was achieved using spectroscopic graphite electrode without any modification. The accuracy of the 4‐NP determination in the presence of 2‐NP, assessed by spike‐and‐recovery experiments was found to be satisfactory. 4‐NP determination was not affected by the presence of a range of structurally similar phenolic compounds.