Determination of Xanthine in the Presence of Ascorbic and Uric Acids on the Glassy Carbon Electrode Modified with Poly(sulfosalicylic acid) Nanorods

作者：Jo Suhee; Jeong Haesang; Bae Si Ra; Jeon Seungwon^*

来源：Bulletin of the Korean Chemical Society, 2008, 29(12): 2407-2412.

• Sulfosalicylic acid
• Electropolymerization
• Nanorods
• Xanthine
• Electrocatalytic oxidation

Poly(sulfosalicylic acid) nanorods (PSSA-NRs) was prepared by electrochemical deposition in PBS solutions, and the PSSA-NRs/GCE modified electrode was investigated by voltammetric methods in buffer solution. The PSSA-NRs/GCE modified electrode demonstrated a substantially enhanced electrochemical sensitivity and selectivity towards xanthine (XA) in the presence of L-ascorbic acid (AA) and uric acid (UA). The PSSA-NRs promoted the electron transfer reaction of XA, while the PSSA-NRs restrained the electrochemical response of the negatively charged AA due to the electrostatic repulsion. The anodic peak potentials of XA, UA and AA were separated by electrochemical techniques, and the interferences from AA and UA were effectively eliminated in the XA determination. The peak currents exhibited two-step linearity according to the XA concentration over the mange from 0.1-10 mu M with a break point of about 1 mu M. The detection limit of the XA oxidation current was 0.02 mu M at a signal-to-noise ratio of 3. The results indicated that the modified electrode can be used to determine XA, without interference from UA and AA, with high sensitivity, selectivity and reproducibility.

• 出版日期2008-12-20