Bismuth film electrode at a silver solid amalgam substrate as a new tool for voltammetric determination of electrochemically reducible organic compounds

New type of bismuth film electrode prepared by electrodeposition of bismuth film on a silver solid amalgam substrate (BiF–AgSAE) was tested as a sensor for voltammetric determination of electrochemically reducible organic substances using 2-amino-6-nitrobenzothiazole (ANBT) as a model analyte. Using the optimized conditions (a 9:1 (v/v) mixture of aqueous Britton–Robinson buffer solution (pH 10.0) and methanol), the limits of quantification are 0.16 μmol L−1 for direct current voltammetry (DCV) and 0.22 μmol L−1 for differential pulse voltammetry (DPV). The obtained calibration dependences are linear in the concentration range from 0.2 to 100 μmol L−1 and the practical applicability of the newly developed electrode for the direct determination of ANBT in tap and mineral water model samples was confirmed in the concentration range from 0.2 to 10 μmol L–1.

► Introduction of a novel bismuth film electrode applicable for cathodic voltammetry. ► First use of silver solid amalgam as a substrate for the bismuth film deposition. ► Sensitive voltammetric determination of genotoxic 2-amino-6-nitrobenzothiazole. ► Developed methods successfully verified on model samples of tap and mineral water. ► Limits of quantification for the determined analyte in submicromolar concentrations.