Voltammetric determination of 2-amino-6-nitrobenzothiazole at two different silver amalgam electrodes

Voltammetric behavior of genotoxic 2-amino-6-nitrobenzothiazole (ANBT) has been investigated using direct current voltammetry (DCV) and differential pulse voltammetry (DPV) at a polished silver solid amalgam electrode (p-AgSAE) and at a mercury meniscus modified silver solid amalgam electrode (m-AgSAE). The optimum conditions have been found for its determination in the concentration range of 0.2-100 mu mol l(-1) in a 9:1 (v/v) mixture of aqueous Britton-Robinson buffer solution (pH 10.0) and methanol, with the limits of quantification (LQS) 0.10 mu mol l(-1) (DCV at p-AgSAE), 0.19 mu mol l(-1) (DPV at p-AgSAE), 0.17 mu mol l(-1) (DCV at m-AgSAE) and 0.12 mu mol l(-1) (DPV at m-AgSAE). An attempt at increasing the sensitivity using adsorptive stripping DCV or DPV at both p-AgSAE and m-AgSAE was not successful. Practical applicability of the newly developed methods was verified on direct determination of ANBT in spiked samples of drinking and river water, with LQS similar to 10(-7) mol l(-1). (C) 2011 Elsevier Ltd. All rights reserved.