REVUE ROUMAINE DE CHIMIE, cilt.60, sa.4, ss.287-295, 2015 (SCI-Expanded)
In this study, a carbon paste electrode based on sepiolite clay (CMCPE) as a modifier has been applied to the voltammetric determination of etoposide (ETZ) by using anodic adsorptive stripping voltammetry. Compared with a bare carbon paste electrode (CPE), CMCPE significantly enhanced the sensitivity toward the target analyte. The experimental conditions optimized for the determination of ETZ in the Square wave adsorptive stripping voltammetric mode (AdsSWV) were as follows: initial potential, 0.50 V vs. Ag/AgCl; final potential, +1.00 V; deposition potential, 0.40 V; deposition time, 30 s, and the scan rate, 100 mV s-1. The developed method offers linearity in the concentration range of 0.01 μmolL -1 – 10 μmolL -1 ETZ with r = 0.9951 and the limit of detection of about 0.00262 μmolL -1. The interaction of ETZ, an anticancer drug, with calf thymus DNA has been studied by Square wave Voltammetry (SWV) and Electrochemical Impedance Spectroscopy methods (EIS).