Collect. Czech. Chem. Commun. 2009, 74, 1697-1713
Published online 2010-02-04 20:19:20

Voltammetric and amperometric determination of N-nitroso antineoplastic drugs at mercury and amalgam electrodes

Karolina Peckováa,*, Lucie Vrzalováa, Vladimír Benckob and Jiří Bareka

a Department of Analytical Chemistry, UNESCO Laboratory of Environmental Electrochemistry, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
b Institute of Hygiene and Epidemiology, 1st Faculty of Medicine, Charles University in Prague, Studničkova 7, 128 00 Prague 2, Czech Republic


A hanging mercury drop electrode and a mercury meniscus modified silver solid amalgam electrode were used as electroanalytical sensors for voltammetric determination of antineoplastic drugs carmustine, lomustine and streptozotocin containing reducible N-nitroso groups. On the example of carmustine it was shown that its one-step reduction proceeds at substantially more negative potentials at amalgam electrode as compared with mercury electrode. Both electrodes offer satisfactory repeatability of current response (relative standard deviations < 5%) using DC voltammetry and differential pulse voltammetry. The achieved limits of determination lie mostly in the 10–7 mol l–1 concentration range. The mentioned voltammetric methods were applied to determination of carmustine and lomustine in pharmaceutical formulations. Further, the mercury meniscus modified silver solid amalgam electrode was employed in a “wall-jet” amperometric detection cell in the determination of carmustine by flow injection analysis. Under optimized conditions (run electrolyte Britton– Robinson buffer of pH 7.0; flow rate 5.5 ml min–1; detection potential –1.5 V; injection volume 0.02 ml) the limit of quantitation 7.1 × 10–6 mol l–1 was achieved.

Keywords: Carmustine; Streptozotocin; Lomustine; Hanging mercury drop electrode; Silver solid amalgam electrode; Nitroso compounds; Voltammetry; Amperometry; Electrochemistry.

References: 47 live references.