【摘要】 制备了羧化多壁碳纳米管/维生素B12修饰玻碳电极,利用循环伏安法研究了多巴胺(DA)在此修饰电极上的电化学行为。结果表明,在pH为6.48的PBS缓冲溶液中,此修饰电极对DA有很强的电催化作用,明显增强了峰电流,峰电位差ΔEp由196 mV减小至69 mV,提高了电极反应的可逆性。在优化实验条件下,此修饰电极所测DA氧化峰电流与DA浓度在1.0×10-5~5.0×10-5mol/L及1.0×10-3~1.0×10-2mol/L范围内均呈线性,线性方程分别为y=373.78x+71.726(R2=0.995 8)和y=57.2x+365.22(R2=0.986 6),其中低浓度区的相关系数较高,应用于实际样品测定时结果较为满意。检测限可达8.0×10-8mol/L。更多还原

【Abstract】 A MWCNT /VB12/GC modified electrode is prepared. The electrochemical behavior of dopamine on the modified electrode is investigated by using cyclic voltammetry. The results indicate that the modified electrode shows excellent electrocatalysis characteristics for dopamine. The peak current increases a lot and the peak potential difference( ΔEp) decreases from 196 mV to 69 mV. The reversibility of the reaction becomes much better. A linear response of the modified electrode to dopamine holds in the concentration range of 1. 0 × 10- 5- 5. 0 × 10- 5mol·L- 1and the range of1. 0 × 10- 3- 1. 0 × 10- 2mol·L- 1under optimal conditions. The linear equations are y = 373. 78 x + 71. 726( R2= 0. 9958) and y = 57. 2x + 365. 22( R2= 0. 986 6),respectively. The modified electrode has been applied to the determination of dopamine in real samples with satisfactory results.更多还原