Electrochemical Behavior of Uric Acid at a Meso-2,3-Dimercaptosuccinic Acid Self-Assembled Gold Electrode
Titel:
Electrochemical Behavior of Uric Acid at a Meso-2,3-Dimercaptosuccinic Acid Self-Assembled Gold Electrode
Auteur:
Niu, Ling Mei Luo, Hong Qun Li, Nian Bing
Verschenen in:
Instrumentation science & technology
Paginering:
Jaargang 35 (2007) nr. 1 pagina's 59-73
Jaar:
2007-02-01
Inhoud:
The fabrication and electrochemical characteristics of a meso-2,3-dimercaptosuccinic acid (DMSA) self-assembled monolayer modified gold electrode were investigated. The DMSA self-assembled electrode can enhance the electrochemical stability of uric acid (UA) and the electrochemical reaction of UA on the DMSA electrode has been studied by cyclic voltammetry and electrochemical quartz crystal microbalance. Some electrochemical parameters, such as diffusion coefficient, standard rate constant, electron transfer coefficient, and protons transfer number have been determined for the electrochemical behavior on the DMSA self-assembled monolayer electrode. The electrode reaction of UA is an irreversible process which is controlled by the diffusion of UA with two electrons and two protons transfer at the DMSA/Au electrode. In phosphate buffer (pH 5.0), the peak current is proportional to the concentration of UA in the range of 8.0×10-5-1.0×10-2 mol L-1 and 8.0×10-5-8.0×10-3 mol L-1 for the cyclic voltammetry and differential pulse voltammetry methods with the detection limits of 1×10-6 and 8×10-7 mol L-1, respectively. This method can be applied to the determination of the UA concentration.