电还原柠嗪酸修饰电极对多巴胺和尿酸的电化学性质研究

Electro-chemical-study of dopamine and uric at an electrode modified with electro-reduced citrazinic acid

采用循环伏安法制备了电还原柠嗪酸膜修饰碳糊电极（ECA／CPE），研究了多巴胺（DA）在该修饰电极上的电化学行为。在pH7．0的磷酸盐缓冲溶液中，ECA／CPE对DA具有明显的电催化作用，且DA呈现出一对准可逆的氧化还原峰，其氧化峰电流与DA浓度在3．7×10^-7-8．2×10^-5mol／L和1．04X10^-4～9．34×10^-mol／L范围内呈良好的线性关系，检出限为4×10^-7moL／L（S／N=3）。使用微分脉冲伏安法，DA和尿酸（UA）在ECA／CPE上的氧化峰能完全分离，且峰电流与浓度呈良好的线性关系。该电极可用于盐酸多巴胺针剂中DA的测定以及人体尿液中UA的检测。

A novel electro-reduced citrazinic acid （CA） film modified carbon paste electrode （CPE） was fabricated by electroreduction method and used to study the electrochemical behavior of dopamine （DA） and uric acid （UA）. The results illustrate that the modified electrode possesses strong catalytic activity on the electro- oxidation of DA and UA, and a pair of well-defined quasi-reversible redox peaks of DA are obtained on ECA/CPE. The proposed sensor exhibited good linearities in ranges of 3.7×10^-7 _ 8.2×10^-5 moL/L and 1.04×10^-4 - 9. 34 ×10^-4 mol/L. The detection limit （S/N = 3 ） was 4×10^-7mol/L by differential pulse vohammetry （DPV）. Besides, the oxidation peaks of DA and UA were completely separated linearly changed with the increase of concentration in presence of UA. The applied to the detection of dopamine hydrochloride injections and urine samples and the peak currents of DA also electrode has been successfully with good reproducibility.