Voltammetric analysis of cocaine using platinum and glassy carbon electrodes chemically modified with Uranyl Schiff base films

Platinum and glassy carbon electrodes chemically modified with films of Schiff bases of [UO2(3-MeOSalen)(H2O)] center dot H2O and [UO2(5-MeOSalen)(H2O)] center dot H2O, to determine cocaine were developed. The stability of these films in aqueous solution containing 1.0 mol L-1 KCl and HCl 1.0 mM in pH 3 as supporting electrolyte and conducted cyclic voltammetric analysis of cocaine in the same supporting electrolyte were investigated. A reversible interaction between cocaine and the working electrodes increased the original peak current of the surface-modifier, according to the employed species. The determination of cocaine using the developed electrodes depended linearly on cocaine concentration in the range 0.54-9.10 mu mol L-1, with amperometric sensitivities of 5.21 x 10(7) and 1.66 x 10(5) mu A mol(-1) L, limits of quantification of 0.29 and 0.50 mu mol L-1, and limits of detection of 0.07 and 0.15 mu mol L-1, respectively. (C) 2013 Elsevier B.V. All rights reserved.