汞膜修饰玻碳电极测定文法拉新的研究

Study of the mercury film modified glass carbon electrode in determination of Venlafaxine

目的:研究形成汞膜修饰玻碳电极的最佳条件及该修饰电极用于药物文拉法新的测定。方法:在含有汞离子的1.0mol·L-1硫酸溶液中,采用在负电位下还原的方法,研究了在玻碳电极(GCE)上修饰汞膜的最佳条件;用循环伏安法测定文拉法新。结果:在玻碳电极上修饰汞膜的最佳条件是:在含有2.0×10-4mol·L-1汞离子的1.0mol·L-1硫酸溶液中,在-0.8V电位还原50s。用循环伏安法测定文拉法新(VEN),在汞膜玻碳电极上VEN的氧化电位为0.33V,且峰电流比在裸玻碳电极要大得多。在测定VEN时,多巴胺、抗坏血酸、葡萄糖、尿素以及一些常见碱金属和碱土金属阳离子及阴离子对文拉法新的测定没有干扰,Ag+、Sb3+、Bi3+等干扰严重。测定VEN的线性范围为:1.5×10-6～6.0×10-4mol·L-1,检出限为8.0×10-7mol·L-1。结论:制得的汞膜玻碳电极具有较好的重现性,且制作方法简便,表面更新容易。用于VEN的测定具有较宽的线性范围和较低的检出限,建立了一种测定VEN的新方法。

Objective： The optimal condition was researched for the preparation of mercury film modified glassy carbon electrode （GCE） and the application of this modified electrode in the detection of venlafaxine （VEN）. Methods ： The optimal condition for preparation of the mercury film modified glassy carbon electrode had been studied by deposition at the negative potential in 1.0 mol·L^-1 H2SO4 containing Hg^2＋. The detection of VEN had been tested by cyclic voltammetry. Results： The optimal conditions for preparation of the mercury film modified glassy carbon electrode was that the electrode was deposition at the potential of -0. 8 V for 50 s in 1.0 mol·L^-1 H2SO4 containing 2.0 10^-4mol ·L^-1 of Hg^2＋. In succession,the concentration of the VEN had been detected by the cyclic voltammetry in 1.0 mol ·L^-1 H2SO4. On the mercury film modified GCE the oxidation potential of the VEN was 0. 33 V and the current of this peak was higher than that on the bare GCE. The linear range of the detection of VEN was 1.5 × 10^-6 -6. 0 ×10^-4 mol·L^-1 and the detection limit was 8. 0 ×10-7 mol·L^-1. Conclusion： The mercury film modified glassy carbon electrode had good stability and reproduction and facility for fabrication and the detection of VEN had wider linear range and lower determination limit. The new method for analyses VEN had been found.