多壁碳纳米管修饰电极差分脉冲伏安法测定酪氨酸.pdfVIP

多壁碳纳米管修饰电极差分脉冲伏安法 测定酪氨酸 邵 晨，卫应亮，冯 辉，王 恒 (郑州轻工业学院材料与化学工程学院河南省表界面科学重点实验室，郑州450002) 摘 要：制备了多壁碳纳米管修饰玻碳电极，研究了酪氨酸在该电极上的电氧化行为并优化了 测定条件。试验表明：与裸玻碳电极相比，该修饰电极明显降低了酪氨酸的氧化电位，提高了酪氨 酸的氧化峰电流；利用差分脉冲伏安法测定其峰电流和酪氨酸的浓度在 3．0×10一。～1．0× 10一 mo1．L 范围内呈线性关系，检出限(S／N一3)为1．6×10 mo1．I _。；一些常见物质对测定 无干扰。此方法已应用于人尿中酪氨酸的测定，测定结果的相对标准偏差(7z一6)在3．1 ～4．5 之间，加标回收率在93．8 ～111．8 之间。 关键词：差分脉冲伏安法；多壁碳纳米管；修饰电极；酪氨酸 中图分类号：0657．1 文献标识码：A 文章编号：1001—4020(2008)06—0553—04 Differential Pulse Voltammetric Determination of Tyrosine with Multi。wall Carbon Nanotube Modified Glassy Carbon Electrode SHAO Chen，WEI Ying-liang，FENG Hui，WANG Heng (Henan Provincial Key Lab．of Surface and Interface Science，Dept．of Material and Chemical Engineering， Zhengzhou College of Light Industry，Zhengzhou 450002，China) Abstract：Preparation and characterization of multi—wall carbon nanotube(MWCNT)modified glassy carbon electrode(( E)was described and electrochemica1 behavior of tyrosine(TRS)at this modified electrode was studied．As shown by experimental results，the oxidation potential of TRS was lowered obviously at the modified electrode，while its oxidative peak current was increased．Linear relationship between values of peak current and concentration of TRS was found to be kept in the range from 3．0×1 0～ to 1．0 X 10一 rnol·L一 ．Detection limit (S／N一3)of the method found was 1．6×10 mo1．L一 when the enrichment time of 4 min was taken．As shown by results of test for interferences，the proposed method was proved to have good selectivity．Based on these facts a differential pulse voltammetric method for determination of tyrosine was proposed．In its application to the determination of TRS in human urine samples，values of RSD s( =6)obtained were in the range from 3．1 to 4．5