Electrochemical behavior of dopamine at dodecyl benzenesulfonate self-assembled monolayers modified electrode and its application
Han, X-xia.; Gao, Z-ning.
Yao Xue Xue Bao 42(4): 413-417
2007
ISSN/ISBN: 0513-4870 PMID: 17633211 Document Number: 611176
Sodium dodecyl benzenesulfonate ( SDBS) self-assembled monolayers in situ modified electrode (SDBS/CPE) was prepared. The electrochemical behaviors of dopamine (DA) on SDBS/CPE were studied. Electrochemical behaviors and kinetic parameters of DA were investigated at SDBS/CPE by cyclic voltammetry ( CV), chronoamperometry ( CA) and chronocoulometry ( CC). The changes of the oxidation peak currents with concentration of DA were examined by square wave voltametry ( SWV). The difference of peak potential at CPB/CPE was less than 149 mV comparing with that at CPE. The charge transfer coefficient alpha, diffusion coefficient D and the apparent reaction rate constant k(f) are 0.61, 3.6 x 10(-5) cm(2) (.) s (-1) and 4.2 x 10(-3) cm (.) s (-1), respectively. The oxidation peak currents of DA versus its concentration have a good linear relationship in the concentration range of 2.0 x 10(-6) - 1.0 x 10(-3) mol (.) L-1 with the correlation coefficient of 0.997 9 and the detection limit of 9.0 x 10(-7) mol (.) L-1 by square wave voltammetry ( SWV) response. The modified electrode showed an excellent electrocatalytic activity for the DA electrochemical oxidation. The method can be applied in the determination of DA in injection samples with the satisfactory results.