Collect. Czech. Chem. Commun. 2011, 76, 1607-1617
https://doi.org/10.1135/cccc2011113
Published online 2012-01-04 08:24:56

Metronidazole radical anion formation studied by means of electrochemical impedance spectroscopy

Miroslav Gála,*, Romana Sokolováa, Viliam Kolivoškaa, Andrea Morovská Turoňováb, Marta Ambrovác and Ján Hívešc

a J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, 182 23 Prague 8, Czech Republic
b P. J. Šafárik University, Faculty of Science, Institute of Chemistry, Moyzešova 11, 040 01 Košice, Slovakia
c Institute of Inorganic Chemistry, Technology and Materials, Department of Inorganic Technology, Faculty of Chemical and Food Technology, Slovak Technical University Bratislava, Radlinského 9, 812 37 Bratislava, Slovakia

Abstract

Radiosensitizers belong to the most important class of the cancerostatic drugs. The electrochemical transfer of the first electron to the cytotoxic radiosensitizer Metronidazole (MET) and MET radical anion formation in aprotic medium was studied by means of electrochemical impedance spectroscopy. The heterogeneous electron transfer rate constant for the first reduction of MET (radical anion production) k0 for the redox couple was determined. Similarly, the diffusion coefficient of MET in dimethylformamide was also calculated by impedance measurements using expression for Warburg coefficient and Warburg plot. Moreover, the equivalent circuit for the redox couple MET/MET•– was proposed and its parameters were evaluated using a non-linear least square fitting. Our results, from the electrochemical point of view, also confirm the suitability of MET for the effective treatment of selected types of the cancer.

Keywords: Radicals; Radiopharmaceuticals; Electron transfer; Impedance spectroscopy; Metronidazole; Radiosensitizers.

References: 38 live references.