酞菁铁修饰碳糊电极测定抗坏血酸的研究

Voltammetric determination of ascorbic acid at a carbon paste electrode modified with iron(Ⅱ) phthalocyanine and dioctyl phthalate

制备了酞菁铁邻苯二甲酸二正辛酯修饰碳糊电极,发现该电极对抗坏血酸的电氧化具有催化作用.在最优化条件下,抗坏血酸的氧化峰电流与其浓度在1.0×10-6～3.4×10-4mol/L范围内成良好的线性关系,检测限为3.2×10-7mol/L.初步讨论了电催化机理.该电极已成功用于果汁和药品维生素C片中的抗坏血酸含量的测定.

Iron(Ⅱ) phthalocyaninedioctyl phthalate modified carbon paste electrode was prepared,it was found that ascorbic acid could be electrocatalyzed oxidation at this electrode.Under the optimum conditions,there was an excellent linearity between the oxidation peak current of ascorbic acid and its concentration in the range of 1.0×10^(-6)~3.4×10^(-4) mol/L,with a detection limit of 3.2×10^(-7) mol/L.The electrocatalytical mechanism of ascorbic acid has also been discussed.The modified carbon paste electrode can be used for the determination of ascorbic acid in the tablet of vitamin C and orange juice with satisfactory results.