Determination of 5-amino-6-nitroquinoline at a carbon paste electrode

Differential pulse voltammetry, direct current voltammetry, adsorptive stripping voltammetry and HPLC with electrochemical detection were used for the determination of 5-amino-6-nitroquinoline at a carbon paste electrode. The methods are based either on anodic oxidation or cathodic reduction of this substance, whose electrochemical behavior at carbon paste electrode was further studied by cyclic voltammetry. Practical applicability of these methods was demonstrated on the determination of 5-amino-6-nitroquinoline in model samples of drinking and river water. The detection limit was 2.0 × 10–6 mol l–1 for anodic differential pulse voltammetry in a mixture of Britton–Robinson buffer (pH 11)–methanol 1:1 (v/v) and 1.6 × 10–7 mol l–1 for HPLC with electrochemical detection (E = +1.2 V) in a mobile phase Britton–Robinson buffer (pH 7)–methanol 1:9 (v/v).