CeO2纳米晶包裹碳纳米管修饰电极对特布他林的电催化测定

Electrocatalytic determination of terbutaline using a multi-wall carbon nanotubes coated ceria nanoparticles modified electrode

制备出CeO2纳米晶包裹碳纳米管修饰玻碳电极,并运用循环伏安法、交流阻抗谱探讨了该电极的电化学特性。研究了特布他林在该修饰电极上的直接电化学行为。实验结果表明,特布他林在该修饰电极上具有良好的电流响应,与裸玻碳电极相比在pH 7.0缓冲溶液中氧化峰电位负移314 mV。采用计时电流法测定特布他林,其氧化峰电流与浓度在5.0×10^-7～1.0×10^-4mol/L范围呈良好线性关系,线性方程为：Ip（μA）=4.952-0.04724c（μmol/L）,线性相关系数为0.9920,检出限为5.0×10^-8mol/L（信噪比为3）。该电极已用于特布他林片剂中特布他林的测定。

A modified glassy carbon （GC） electrode was fabricated by ceria nanoparticles supported on multi-wall carbon nanotubes （MWNT）. Cyclic voltammetry （CV） and electrochemical impedance spectroscopy （EIS） were used to characterize the electrode modified process. The CeO2/MWNT/GC electrode showed potential electrocatalytic activity toward the electrochemical oxidation of terbutaline in phosphate buffer solution （pH 7.0） with a diminution of the over- potential of 314 mV. The linear dependence between the oxidation peak height of terbutaline and its concentration was observed in the range from 5.0 × 10^-7 to 1.0 × 10^-4 mol/L with a detection limit of 5.0 × 10^-8 mol/L （at a S/N = 3）. The determinations of terbutaline in tablets were carried out and satisfactory results were obtained. Amperometric application of the CeO2/MWNT/GC electrode as biosensors was proposed.