摘要
利用电沉积法制备了Yb-In-Co-MoO24-杂多核氰桥混配物预修饰的玻碳电极,并以该修饰电极为基底,在其表面旋涂壳聚糖,成功制备了一种新型的复合修饰电极.采用示差脉冲伏安法研究了NADH在修饰电极上的电催化氧化行为,与裸电极相比,NADH在修饰电极上的氧化峰电位负移了大约20 mV,氧化峰电流增加了约10倍,NADH的氧化峰电流与其浓度在4～1 000μmol.L-1的较宽范围内呈良好的线性关系;通过计时库仑法测得复合膜修饰电极上NADH电氧化反应的表观异相催化速率常数为9.94×10-3 cm.s-1.此外,实验结果表明,新制备的电极在含NADH的溶液中用循环伏安预扫描15圈后,工作电极上NADH的峰电流测量值趋于稳定,一定程度上消除了因电极的毒化作用对测定结果产生的影响,复合修饰膜中的两种修饰物对NADH的电化学氧化过程有明显的协同催化作用.
The glassy carbon（GC） electrode modified with Yb-In-Co-MoO2-4/Chitosan layer-by-layer composite film is successfully prepared for the first time and the electrochemical oxidation of NADH on this modified electrode is studied in detail by using differential pulse voltammetry.Compared with the voltammetric behavior of NADH on a bare GC electrode,the results show that the oxidation peak potential shifts negatively more than 20 mV and the oxidation peak current increases about ten times on the modified electrode.There exists the wide linear relationship between the oxidation peak current of NADH and its concentration in a range of 4 to 1 000 μmol·L-1.The heterogeneous rate constant for the oxidation of NADH on the modified electrode surface is also determined and found to be 9.94×10-3 cm·s-1.Furthermore,the results demonstrate that if the pretreatment process of 15 cyclic scans are performed on the modified electrode in the solutions containing NADH before each new prepared electrode is used,the measurable value of the peak current for testing NADH samples would tend to stable and the effect of electrode poisoning on the measurement results is eliminated to some extent.The composite film exhibits a good cooperative catalytic action toward the electrooxidation reaction of NADH.
出处
《西北师范大学学报（自然科学版）》
CAS
北大核心
2013年第1期55-60,共6页
Journal of Northwest Normal University(Natural Science)
基金
甘肃省自然科学基金资助项目(096RJZA117)
关键词
NADH
电化学氧化
修饰电极
NADH
electrochemical oxidation
modified electrode
