维生素B_(12)在多壁碳纳米管修饰玻碳电极上的电化学行为及其分析测定  

Electrochemical Behavior and Determination of Vitamin B_(12) at Multi-Wall Carbon Nanotubes Modified Glassy Carbon Electrode

作　　者：向伟[1] 李将渊[1] 马曾燕[1] 

机构地区：[1]西华师范大学化学化工学院,南充637002

出　　处：《应用化学》2007年第8期921-924,共4页Chinese Journal of Applied Chemistry

基　　金：四川省教育厅重点科研项目(2004A106)

摘　　要：制备了多壁碳纳米管修饰玻碳电极(MWNT/GCE),研究了该电极对维生素B12(VB12)的电催化作用并测定VB12的分析条件。结果表明,在以0.1mol/LKCl为支持电解质,pH=7.0的磷酸缓冲溶液中,VB12在MWNT/GCE电极上出现2组氧化还原峰,式量电位分别为-0.10和-0.85V。VB12在-0.85V附近的还原峰电流的一次导数值与其浓度在1×10-8～4×10-7mol/L范围内具有良好的线性关系,其关系式为i′p=5.958×10-7+2.885c(R=0.995),检出限为1.5×10-9mol/L。以该电极对VB12样品进行测定,回收率为97.3%～107.8%。Multi-wall carbon nanotubes modified glassy carbon electrode （MWNT/GCE） was prepared, and the electrocatalysis of vitamin B12 （ VB12 ） and analytic conditions of VB12 on the electrode were studied. The results indicate that two pairs of redox peaks of VB12 at MWCNT/GCE are obtained by cyclic voltammetry in the mixture of 0. 1 mol/L KCl as supporting electrolyte and phosphatic buffer solution（ pH =7.0）. The formal potentials are -0. 10 V and -0. 85 V（vs. SCE）, respectively. The 1st order derivative of the current of reduction peak at - 0. 85 V is linearly related to the concentration of VB12 in the range of 1×10^-8 - 4 ×10^-7 mol/L, which obeys the equation i＇p = 5. 958 ×10^-7 ＋2. 885c（ R = 0. 995 ） and the detection limit can reach to 1.5 ×10^-9 mol/L. This electrode has been applied to directly determining VB12 in tablets with a recovery of 97.3% - 107. 8%.

关 键 词：维生素B12 多壁碳纳米管 循环伏安法 修饰电极 

分 类 号：O657.1[理学—分析化学]