多壁碳纳米管修饰玻碳电极选择性测定色氨酸.pdfVIP

第36卷第5期 华中科技大学学报(自然科学版〉 Vo l. 36 No.5 2008年 5 月 J. Huazhong Univ. of Sci. . Tech. (Natural Science Edition) May 2008 多璧碳纳米管修饰玻碳电极选择性测定色氨酸 郑费琼a 杨昌柱a 张敬东b 潢文虹a (华中科技大学 a 环境科学与工程学院; b 化学与化工系，湖北武汉 430074) 摘要z 研究了色氨酸(Trp) 和酶氨酸(Tyr) 在多壁碳纳米管修饰玻碳(MWNTs/GC) 电极上的电化学行为.结 果表明相对于玻碳电极，此修饰电极促进了色氨酸和醋氨酸的电催化.信号与背景电流比表明相对于醋氨酸 此电极对色氨酸奋更强的催化作用.在1. 0 mol/ L 硫酸中此修饰电极对色氨酸和酶氨酸的分离效果最好，故 6 可以在酶氨酸存在下选择性测定色氨酸.混合液中色氨酸的氧化峰电流与浓度在 7.50X lO- - 2.00XIO寸 mol/L 范围内呈良好线性关系，检出限为 3. 29 X 10-. mo l/L (信噪比为 3). 将此方法用于 17AA 复方氨基酸 注射液中色氨酸的回收试验，回收率达到 97 %以上. 关 键 词s 色氨酸s 酶氨酸$多壁碳纳米管z 玻碳电极z 选择性测定 中团分类号: 0657.1 文献标识码:A 文章编号: 1671-4512(2008)05-0125-04 Selective detection of tryptophan using multiwall carbon nanotube modified glassy carbon electrode Zheng Yanqiong. Yang Changzhu Zhang ] ingdong b Pu Wenhong. (a College of Environmental Science and Engineering ,b Department of Chemistry and Chemical Engineering , Huazhong University of Science and Technology , Wuhan 430074 , China) Abstract: Electrochemical behaviors of tryptophan (Trp) and tyrosine (Tyr) on multi-walled carbon nanotubes modjfied glassy carbon (MWNTs/GC) electrode were studied. The result demonstrates that MWNTs/GC electrode greatly catalyzed the oxidation of Trp and Tyr compared with glassy car- bon electrode. The ratio of signal and background current indicates that the modified electrode cataly- zes more greatly Trp than Tyr. pH test result demonstrates that Trp and Tyr could be separated in 1. 0 mol/L HzSO. solution , which provides the possibility of selective detection Trp in the presence of Tyr. In the mixture , the peak current of