Article

Selective determination of uric acid in the presence of ascorbic acid at poly(p-aminobenzene sulfonic acid)-modified glassy carbon electrode

People’s Hospital of Gansu Province Lanzhou 730000 People’s Republic of China; Chinese Academy of Sciences Graduate School Beijing 100039 People’s Republic of China
Journal of Applied Electrochemistry (Impact Factor: 1.84). 12/2009; 39(12):2323-2328. DOI: 10.1007/s10800-009-9916-0

ABSTRACT The electrocatalytic behavior of uric acid has been investigated with a glassy carbon electrode modified with p-aminobenzene sulfonic acid through electrochemical polymerization. This resulting electrode shows an excellent electrocatalytic
response to uric acid and ascorbic acid, with a peak-to-peak separation of 0.267V in a 0.1molL−1 phosphate buffer solution (PBS) at pH 7.0. These results indicate that the proposed electrode can eliminate the serious interference
of ascorbic acid, which coexists with uric acid in body fluids. Differential pulse voltammetry (DPV) was used for detecting
uric acid with selectivity and sensitivity. The anodic peak current of uric acid was proportional to its concentration in
the range of 1.2×10−7–8.0×10−4molL−1, with a detection limit of 4.0×10−8molL−1. The proposed method has been applied with satisfactory results to the determination of uric acid in human urine without
any pretreatment.

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