基于多壁碳纳米管化学修饰电极直接测定饮料中的麦芽酚  

Direct Electrochemical Determination of Maltol in Beverages at Multi-walled Carbon Nanotubes Modified Electrodes

作　　者：周君[1] 狄俊伟[1] 吴莹[1] 屠一锋[1] 

机构地区：[1]苏州大学化学化工学院,苏州215123

出　　处：《应用化学》2008年第1期81-84,共4页Chinese Journal of Applied Chemistry

基　　金：江苏省教育厅自然科学基金资助(05KJB150123)

摘　　要：采用循环伏安法和示差脉冲伏安法研究了麦芽酚在多壁碳纳米管修饰电极上的电化学行为，建立了一种直接测定饮料样品中麦芽酚含量的电分析测试方法。在pH=8．5的NH3·H2O—NH4Cl缓冲溶液中，麦芽酚在多壁碳纳米管修饰电极上于0．55 V（vs．SCE）产生不可逆的氧化峰。该修饰电极对麦芽酚的电化学反应具有促进作用，阳极峰电流与溶液中麦芽酚的浓度成正比，线性范围为5．0×10^-6～9．0×10^-4mol／L，检出下限为2．0×10^-6mol／L。对含5．0×10^-5mol／L的麦芽酚溶液平行测定10次的相对标准偏差（RSD）为1．1％。多壁碳纳米管修饰电极具有良好的电极稳定性，可用于饮料样品中麦芽酚的直接测定，避免了繁复费时的样品前处理过程。将该修饰电极用于啤酒、可乐和葡萄酒样品中麦芽酚测定，回收率为98％～103％。The electrochemical behavior of maltol at a multi-walled carbon nanotube （MWNTs） modified glassy carbon electrodes was investigated by cyclic vohammetry （CV） and differential pulse vohammetry （DPV）. A direct electroanalytical method for the determination of maltol in beverages was developed. In the medium NH3 · H2O-NH4Cl（pH =8.5）, mahol produces an irreversible oxidation peak at 0.55 V（vs. SCE） on the MWNTs modified electrode. The modified electrode exhibits good performance for the electrochemical reaction of maltol. The anodic peak current of mahol is linearly dependent on its concentration in a range from 5.0 × 10^-6 to 9.0 × 10^ -4 moL/L, with a detection limit of 2. 0 ×10^-6 mol/L. The relative standard deviation is 1.1% for a solution containing 5.0 × 10^-5 moL/L mahol（n = 10）. This modified electrode has a good stability. It can be applied to the direct determination of mahol in beverages without complicated and time-consuming pretreatment. The modified electrode has been satisfactorily used for the determination of maltol in beer, cola and grape wine. The recoveries are in a range of 98% - 103%.

关 键 词：碳纳米管 伏安法 麦芽酚 化学修饰电极 

分 类 号：O657.1[理学—分析化学]