Abstract
Tetrazepam dissolved in the Britton-Robinson universal buffer of various pH values (2.5-11.5) containing 10 vol. % of ethanol was reduced at the mercury electrode in a single 2-electron irreversible step due to reduction of the 4,5 C=N double bond of the seven-membered ring. Differential pulse polarography (DPP) and adsorptive cathodic stripping voltammetry (AdCSV) techniques (Linear sweep LS, differential pulse DP and square-wave SW modes) for quanti. cation of tetrazepam in bulk form and in myolastan tablets are presented. Moreover, the described linear sweep, differential pulse, and square-wave adsorptive cathodic stripping voltammetry was successfully applied in quanti. cation of tetrazepam in spiked human serum without any prior extraction of the drug. The obtained results showed an increased sensitivity of the described electro-analytical procedures for the quanti. cation of tetrazepam in the following order DPP, DP-AdCSV, LS-AdCSV, and SW-AdCSV, since the observed limits of tetrazepam quantitation by these electroanalytical techniques were 5 x 10(-6) mol L-1, 3 x 10(-7) mol L-1, 1 x 10(-8) mol L-1, and 3 x 10(-9) mol L-1, respectively. (c) 2008 Institute of Chemistry, Slovak Academy of Sciences.