Determination of Drimarene Blue X-BLN at a glassy carbon electrode by differential pulse voltammetry

The electrochemical oxidation behaviour of Drimarene Blue X-BLN (DB) has been investigated in phosphate buffers (pH 2.54–10.18) by cyclic and differential pulse voltammetry (DPV) at a glassy carbon electrode (GCE). The oxidation of DB dye generated well-defined pH-dependent two pairs of quasi-reversible anodic-cathodic peak couples. DB exhibited the second redox couple over the entire pH range, while the first redox couple disappeared for pH ≥ 6.70. The redox processes were adsorption-controlled. An electroanalytical method was developed for the determination of DB in phosphate buffer solution (pH 2.85) as supporting electrolyte using DPV. The anodic current heights varied linearly with DB concentrations in the ranges 2 × 10–6–3 × 10–5 and 6 × 10–6–3 × 10–5 mol l–1 with limits of detection (LOD) of 8.7 × 10–7 and 5.7 × 10–7 mol l–1 and limits of quantification (LOQ) of 2.9 × 10–6 and 1.9 × 10–6 mol l–1 for the first and second anodic peaks, respectively. Validation parameters, such as accuracy, precision and recovery were evaluated. The proposed method was successfully applied to the determination of DB in tap water and the analytical results compared well with those obtained by the spectrophotometric method.