聚L-苯丙氨酸修饰电极测定尿酸

Determination for Uric Acid by Poly(L-phenyl alanine) Modified Electrode

用循环伏安法制备聚L-苯丙氨酸修饰玻碳电极,研究尿酸在聚L-苯丙氨酸修饰电极上的电化学行为,建立循环伏安法测定尿酸的新方法.在pH 4.0的磷酸盐缓冲溶液中,尿酸在聚L-苯丙氨酸修饰玻碳电极上出现一氧化峰,峰电位为Epa=+638m V(相对于Ag/AgCl电极),氧化峰电流与尿酸浓度在5.00×10-7～5.00×10-5m ol/L范围内成线性关系,检测限:1.0×10-7m ol/L.对1.0×10-5m ol/L UA溶液平行测20次,其相对标准偏差为3.1%.用于尿液中尿酸的测定,结果满意.

In this paper, the poly （L- phenyl alanine） modified electrode was prepared, and the vohammetric behavior of uric acid and cyclic vohammetric method determination of uric acid at the poly （L - phenyl alanine） modified electrode were studied. In pH4.0 phosphate buffer solution, the anodic peak of uric acid was observed at ＋ 638 mV（vs Ag/AgCl ）, the anodic peak current was in linear relationship with uric acid concentration in the range of 5.00 × 10^-7 mol/L - 5.00 × 10^-5 mol/L. The detection limit was 1.0 × 10^-7 mol/L. The relative standard deviation was 3.1% （n=20, 1.0 × 10^-5 mol/L uric acid）.The method has been applied to the determination of uric acid in urine with satisfactory results.