聚乙烯基吡咯烷酮-多壁碳纳米管复合修饰玻碳电极用于差分脉冲伏安法测定抗坏血酸

Differential Pulse Voltammetric Determination of Ascorbic Acid with PVP-MWCNT′s/GCE

摘要: 采用超声辐射法制备了聚乙烯基吡咯烷酮(PVP)-多壁碳纳米管(MWCNT′s)复合材料(PVP-MWCNT′s),将该复合材料分散在N,N-二甲基甲酰胺(DMF)中并滴涂在玻碳电极表面,制备了聚乙烯基吡咯烷酮-多壁碳纳米管复合修饰玻碳电极(PVP-MWCNT′s/GCE)。研究发现:抗坏血酸在修饰电极上出现一对可逆的氧化还原峰,提出了用差分脉冲伏安法测定抗坏血酸的方法。还原峰电流与抗坏血酸的浓度在1.0×10-7~1.0×10-3mol·L-1范围内呈线性关系。

Abstract: Through the action of ultrasonic radiation, the composite material of polyvinylpyrrolidone (PVP) and multiwall carbon nanotubes (MWCNT′s) was prepared and dispersed in N,N-dimethylformamide (DMF). The dispersion was then dropped onto the surface of glassy carbon electrode (GCE) to give the modified electrode, designated abbreviately as PVP-MWCNT′s/GCE. It was found that ascorbic acid showed a pair of reversible oxidation and reduction peaks at PVP-MWCNT′s/GCE. Based on this finding, a selective method for the determination of ascorbic acid by differential pulse voltammetry was proposed. Linear relationship between values of reduction peak current and concentration of ascorbic acid was obtained in the range of 1.0×10-7-1.0×10-3mol·L-1.