Electrochemical determination of uric acid using a mesoporous SiO2-modified electrode

A mesoporous SiO2-modified carbon paste electrode for the determination of uric acid is described. Owing to the regular and specific mesoporous channels, numerous active sites and a large surface area, the mesoporous SiO2-modified electrode greatly increases the oxidation peak current of uric acid. Based on this, a highly sensitive, rapid and convenient electrochemical method was developed for the determination of uric acid after optimizing the experimental parameters (supporting electrolyte, content of mesoporous SiO2, accumulation potential and time). The linear range is from 2.5 × 10−7 to 2.0 × 10−5 mol L−1, and the limit of detection is estimated to be 8.0 × 10−8 mol L−1. The relative standard deviation for 10 mesoporous SiO2-modified electrodes is 5.8%. The method was used to determine uric acid in human serum samples.