正弦波伏安法检测尿酸的研究

Research on the Use of Sinusoidal Voltammetry to Determination of Uric Acid

以玻碳电极为工作电极,利用正弦波伏安法在磷酸缓冲液中选择性检测尿酸。通过傅立叶变换比较了纯的磷酸缓冲液、尿酸和抗坏血酸的正弦波伏安法频域响应,进而发现在第5次谐波处选择性检测尿酸的可能。相比于传统的尿酸检测技术,该技术具有较高的信噪比,操作简单且无需对样品进行预处理。分析了玻碳电极表面抗坏血酸和尿酸的线性扫描响应,在不同扫描速率下两者的伏安图变化趋势相同。在裸玻碳电极表面,利用正弦波伏安法检测尿酸的检测限为1.0μmol/L,在250倍浓度的抗坏血酸共存时仍能利用第5次谐波选择性检测出尿酸。

The present work is to demonstrate the selective determination of uric acid in phosphate buffer by sinusoidal voltammetry at glassy carbon electrode. After comparison of frequency response of pure phosphate buffer, uric acid and ascorbic acid by Fourier Transform,we obtain the possibility to determinate uric acid in fifth harmonic. In this method, we attain upper signal-nosie rate over traditional uric acid detection methods. We also study the linear sweep response of uric acid and ascorbic acid in glassy carbon electrode, and find both voltammograms have the same change trends in different scan rate. In the experiments, the detection limit of uric acid is 1.0μmol/L,and in the presence of 250-fold excess of AA we also can detect uric acid in the fifth harmonic.