辅酶I在钴/玻碳离子注入修饰电极上的电化学行为及其应用研究

Electrochemical Behavior of Coenzyme I and Its Application on Glassy Carbon Ion Implantation Modified Electrode

辅酶I(NAD)在 0 .0 0 5mol/LTris 0 .0 1mol/LNaCl(pH =7.0 )缓冲溶液中 ,在Co/GC离子注入电极上有一良好的伏安还原峰 ,峰电位Ep=- 1 .0 7V (vs .SCE)。其峰电流与辅酶I (NAD)的浓度在 5 .0× 1 0 -5～ 1 .0×l0 -3 mol/L范围内呈线性关系 ;检出限为 2 .5× 1 0 -5mol/L ;回收率在 98.8%～ 1 0 1 .9%之间。用线性扫描和循环伏安法等方法研究该体系的电化学行为 ,实验表明 :该体系具有吸附性和催化性的不可逆过程。根据Laviron理论 ,求得电极表面反应速率常数Ks=0 .0 77/s;电子转移系数α =0 .4 35。

With Co/glassy carbon (GC) ion implantation modified electrode as working electrode, in 0.005 mol/L Tris-0.01 mol/L NaCl (pH = 7. 0) buffer solution, a sensitive reduction peak of coenzyme I (NAD) was obtained by linear sweep voltammetry. The peak potential was -1. 07 V (vs. SCE). The peak current was proportional to the concentration of NAD over the range of 5.0 X 10(-5) similar to1.0 x 10(-3) mol/L, with a detection limit of 2.5 X 10(-5) mol/L. The recoveries were of 98.8% to 101.9%. The electrochemical behavior of the system was studied by linear sweep and cyclic voltammetry. The experiment results showed that the reduction process at Co/GCE was irreversible with adsorption and catalysis. According to Laviron theory, the electrode reaction rate constant K. and the electron transfer coefficient a were calculated to be 0.077/s and 0.435, respectively.