基于聚N-甲基苯胺/Ni^(2+)修饰玻碳电极的无酶葡萄糖传感器研究

Study of the Enzyme-free Glucose Biosensor Based on Poly(N-methylaniline)/Ni^(2+) Modified Glassy Carbon Electrode

在0.50mol.L-1 HClO4溶液中,采用循环伏安法在玻碳(GC)电极上修饰聚N-甲基苯胺(PNMA)薄膜,然后将电极浸泡在1.0mol.L-1 Ni(NO3)2溶液中,使Ni 2+渗入PNMA薄膜中得到PNMA/Ni 2+/GC电极,研究了该修饰电极的伏安特性及对葡萄糖的电催化氧化行为。实验结果表明,在0.10mol.L-1 NaOH介质中,PNMA/Ni 2+/GC电极对葡萄糖具有较强的电催化活性;在工作电位为+0.5V条件下,该电极对葡萄糖的响应时间小于2s,葡萄糖浓度在0.025～5.70mmol.L-1范围内与其氧化电流呈现良好的线性关系,相关系数R=0.9996,检出限为0.01mmol.L-1,葡萄糖测定的回收率在98%～104%之间。抗坏血酸、尿酸的干扰可利用Nafion消除。该修饰电极是一种较好的无酶葡萄糖传感器。

At first,the poly（N-methylaniline）（PNMA）film was formed on the glassy carbon electrode by cyclic voltammetric method in 0.50 mol·L-1 HClO4 solution.Then,Ni2＋ ions were incorporated by immersion of the modified electrode in a 1.0 mol·L-1 Ni（NO3）2 solution.Thus,a poly（N-methylaniline） /nickel modified glassy carbon electrode was obtained.The electrochemical characteristics and the electrocatalytic activity for glucose oxidation of this modified electrode were investigated.The results showed that PNMA / Ni2＋ / GC electrode exhibited high electrochemical activity towards the oxidation of glucose in 0.1 mol·L-1 NaOH solution.At an applied potential of ＋0.50 V,it gave a fast response time（2 s） and exhibited a linear response to glucose over the range from 0.025～5.70 mmol·L-1（R=0.9996）.The detection limit of glucose was 0.01 mmol·L-1.The standard addition recoveries of glucose were 98%～104%.The interference caused by the interfering species,such as ascorbic acid and uric acid,could be effectively avoided by using Nafion.This electrode is a fairly good enzyme-free glucose biosensor.