Artículos de revistas
Electrochemical behavior of dopamine at a 3,3 '-dithiodipropionic acid self-assembled monolayers
Registro en:
Talanta. Elsevier Science Bv, v. 72, n. 2, n. 427, n. 433, 2007.
0039-9140
WOS:000246321200014
10.1016/j.talanta.2006.10.045
Autor
Codognoto, L
Winter, E
Paschoal, JAR
Suffredini, HB
Cabral, MF
Machado, SAS
Rath, S
Institución
Resumen
Monolayers of 3,3'-dithiodipropionic acid (DTDPA) were prepared on a polycrystalline gold electrode through a self-assembly procedure to produce a gold 3,3'-dithiodipropionic acid self-assembled monolayer (AuDTDPA) modified electrode. The characterization of the AuDTDPA electrode was investigated by cyclic voltammetry and ac impedance using the [Fe(CN)(6)](3-/4-) redox couple. The electrochemical behavior of DA on the modified electrode AuDTDPA was studied by cyclic and square-wave voltammetries, using phosphate buffer as supporting electrolyte. The oxidation peak current for DA increases linearly with concentration in the range of 0.35 x 10(-5) to 3.4 x 10(-5) mol L-1. The performance of the AuDTDPA modified electrode was evaluated for the electroanalytical determination of dopamine (DA) in a pharmaceutical formulation. The AuDTDPA modified electrode showed a stable behavior and the presence of surface-COOH groups avoided the passivation of the electrode surface during the dopamine oxidation. (c) 2006 Elsevier B.V. All rights reserved. 72 2 427 433