Application of N-4,4ʹʹ-azodianiline(ferrocenyl Schiff base) for electrocatalytic determination of atenolol on modified carbon paste electrode

A carbon-paste electrode (CPE) chemically modified with the N-4,4ʹ-azodianiline(ferrocenyl Schiff base) complex and multi wall carbon nanotubes (ADAFCNTE) was used as a highly sen-sitive electrochemical sensor for determination of trace amounts of atenolol. The oxidation peak potentials in cyclic voltammogram of ADAFCNTE occurred around 550 mV vs Ag/AgCl (at pH 6.0) while this peak potential at the carbon paste electrode appeared around 800 mV at the same scan rate of 10 mV s?1. The kinetic parameters such as electron transfer coefficient, ?, and rate constant for chemical reaction between atenolol and redox sites in modified electrode were 0.41 and 2.8×102 cm3 mol-1 s-1, respectively. The catalytic peak current was linearly dependent on atenolol concentration in the range of 0.1-57.0 µmol L-1 with a detection limit of 0.08 µmol L-1. Finally, the sensor was examined as a selective, simple and precise new electrochemical sensor for the determination of atenolol in urine samples, with satisfactory results.