碳纳米管修饰电极的制备及其对NADH的电催化氧化

Carbon nanotube-modified electrode and the electro-catalytic oxidation of NADH

采用丝网印刷技术,制备出羧基化多壁碳纳米管修饰的丝网印刷碳电极,并采用循环伏安法研究了该电极对还原型烟酰胺腺嘌呤二核苷酸(NADH)的电催化氧化性能。结果表明,与未修饰丝网印刷碳电极相比,多壁碳纳米管修饰丝网印刷碳电极显著降低了NADH的氧化峰电位,消除了反应产物对电极的污染及其它电化学反应对测量的干扰。将修饰电极与流动注射系统结合起来,建立了利用电流—时间曲线测量NADH浓度的方法。在1μmol/L^6mmol/L的范围内,响应电流与NADH的浓度有较好的线性关系,其线性回归方程为i(nA)=1.5114c(μmol)+0.11762,相关系数为0.9915,检测限为0.7μmol/L。

In this paper, the carboxylated multi-walled carbon nanotube-modified screen-printed carbon electrodes are prepared. Based on the cyclic voltammetry , the electro-catalytic oxidation of the modified electrodes on the nieotinamide adenine dinucleotide （NADH） is researched. The results show that multi-walled carbon nanotube-modified electrodes can make the oxidation peak potential of NADH reduced significantly compared with unmodified screen-printed carbon electrodes, avoid the reaction products to contaminate electrodes and make interference to other electrochemical reactions . Based on the modified electrodes and a flow-injection system , a method for measuring the concentration of NADH is put forward by using the current-time curve. In the range of 1μmol/L-6mmol/L, the response currents are keep in good linear relation with the concentration of NADH with the linear regression equation of i（nA）= 1.5114c（μmol） ＋ 0.11762, the correlation coefficient of 0.9915, and the detection limit of 0.7μmol / L