摘要:用疏水性离子液体1-丁基-3-甲基咪唑六氟磷酸([BMIM] PF6)作粘合剂制备了离子液体修饰碳糊电极(IL/CPE).采用循环伏安法(CV)研究了维生素E( vitamin E,VE)的氧化产物生育酚红在IL/CPE和未修饰碳糊电极(CPE)上的电化学行为,结果表明生育酚红在IL/CPE上氧化过程更易于进行,峰电流响应ip也明显增加,表明IL/CPE对生育酚红的氧化还原反应具有良好的电催化作用.同时测定了电极过程的动力学参数:电荷转移系数c=0.8746,扩散系数D=1.65×10-3cm2/s,电极反应速率常数kt=6.64× 10-2cm/s.采用方波伏安法(SWV)发现生育酚红氧化峰电流与其浓度在1.53× 10-4mol/L～8.39×10-7mol/L范围内呈线性关系,检出限为1.58× 10-8mol/L.该法可用于VE实际样品的分析测定.%An ionic liquid modified carbon paste electrode( IL/CPE) was fabricated by employing hydrophobia ionic liquid 1-butyl-3-melhylinudazolmm hexafluorophosphate( [BMIM]PF5)as a binder. The electrochemical behavior of tecored(the oxidation product of vitamin E) at the IL/CPE and non-modified CPE was investigated by cyclic voltamnietry( CV). The experimental results show that the oxidation process of tecored at the IL/CPE was much more easier,while peak current ipwas significantly increased,which indicated that IL/CPE had electrocatalytic activity toward the redox of vitamin E. At the same time some kinetics parameters of the vitamin E were determined at IL/CPE;electron transfer coefficient a is 0.8746Tthe Diffusion coefficient D is 1. 65×10-3cmVs and the e-lectrode reaction rate constant kf is 6.64×10-2cm/s. The linear relationship between values of oxidation peak current and concentra-tion of vitamin E was found in the range from l,53×10-4mol/L to 8.39×10-7mol/L with a detection limit of 1.58×10-8mol/L(S/ N=3)by Square Wave Voltametry(SWV)method. The proposed method was applied to directly analysis and determines vitamin E samples.
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