Cyclic Voltammetric Studies of Dopamine at Lamotrigine and TX-100 Modified Carbon Paste Electrode

This paper describes the procedure that has been optimized for the determination of dopamine at Lamotrigine modified carbon paste electrode (LTGMCPE) by cyclic voltammetry with 0.2M phosphate buffer at pH 7. The carbon paste electrode (CPE) was modified by Lamotrigine and Triton-X-100 (TX-100). The LTGMCPE and TX-100 immobilized CPE (TX/LTGMCPE) showed very good sensitivity for dopamine. The scan rate effect at both LTGMCPE and TX/LTGMCPE was studied. Increase of TX-100 showed linear increase in redox peak currents of dopamine. Mechanism of electrocatalytic oxidation of dopamine and ferrocyanide at the surface of the Lamotrigine modified CPE containing various percents of TX-100 is thoroughly investigated. The favorable ionic interaction (electrostatic repulsion) between the cationic form of DA and a non ionic surfactant (TX-100). The preparation of the modified electrode is very easy and renewed by simple polishing gives very good reproducibility, high stability in its voltammetric response and low detection limit for DA.