The nano-Au self-assembled glassy carbon electrode for selective determination of epinephrine in the presence of ascorbic acid

Gold nanoparticles were self-assembled to the modified glassy carbon electrode (GC) with cysteamine (CA) to prepare the nano-Au/CA/GC modified electrode. The electrochemical behavior of epinephrine (EP) on the modified electrode was explored with cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Epinephrine gave a pair of redox peaks at E-pa = 0.190 mV and E-pc = -0.224 mV (versus SCE), respectively. The nano-Au/CA/GC modified electrode shows an excellent electrocatalytic activity for the oxidation of EP. The modified electrode could be used to determine EP in the presence of ascorbic acid (AA). The response of catalytic current with EP concentration shows a linear relation in the range of 1.0 x 10(-7) to 5.0 x 10(-4) mol L-1 with the correlation coefficient of 0.998. The detection limit is 4.0 x 10(-8) mol L-1. The modified electrode exhibited a good reproducibility, sensitivity and stability for the determination of EP injection. (C) 2006 Elsevier B.V. All rights reserved.