多壁碳纳米管修饰玻碳电极测定乳糖酸红霉素

Determination of Erythromycin Lactobionate with Multi-Wall Nano-Carbon Tube Modified Glassy Carbon Electrode

用化学方法对多壁碳纳米管进行表面处理，能够使处理后的碳纳米管变短并且在其表面引入了羧基等活性功能团。将化学处理后的多壁碳纳米管用于修饰玻碳电极，研究发现碳纳米管修饰电极对乳糖酸红霉素有良好的电催化作用，能够显著提高氧化峰电流。优化了测定参数，在此基础上建立了一种直接测定乳糖酸红霉素的电分析方法。试验结果表明：乳糖酸红霉素的氧化峰电流与其浓度在2．0×10^-5～1．8×10^-3mol·L^-1范围内呈线性关系，相关系数为0．9951；检出限为6．3×10^-7mol·L^-1。用此方法分析了注射用的乳糖酸红霉素粉剂样品，所得结果与标示值一致。用标准加入法进行了回收率试验，所得结果在97．3％～104．0％之间。

Abstract： Multi-wall nano-carbon tubes （MWNT＇s） were treated by chemical method to make their length shorter and to introduce active functional groups, such as carboxyl group and etc., onto their surface. The chemically treated MWNT was used to modify glassy carbon electrode （GCE）. It was found that significant catalytic action of the MWNT modified GCE was observed on the reaction of erythromycin lactobionate at the electrode, with its oxidation peak current increased remarkably as compared with its reaction at the bare GCE. The reaction conditions were studied and optimized, and an electrochemical method was proposed for the determination of erythromycin lactobionate. Linear relationship between the oxidation peak current and concentration of erythromycin lactobionate was obtained in the range of 2.0×10^-6 -1.8×10^-3 mol·L^-1 （r=0.995 1） with its detection limit achieved to 6.3 ×10^-7 mol·L^-1. In analyzing a substantial sample of erythromycin lactobionate powder used for injection, the result obtained was conformed to the labelled value of the drug, and the values of recovery found by standard addition method were in the range from 97.3% to 104.0%.