Wang Po, Li Yongxin, Huang Xue, Wang Lun
Anhui Key Laboratory of Functional Molecular Solids, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, PR China.
Talanta. 2007 Sep 30;73(3):431-7. doi: 10.1016/j.talanta.2007.04.022. Epub 2007 Apr 25.
A novel electrochemical sensor has been constructed by use of a glassy carbon electrode (GCE) coated with a gold nanoparticle/choline (GNP/Ch). Electrochemical impedance spectroscopy (EIS), field emission scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize the properties of this modified electrode. It was demonstrated that choline was covalently bounded on the surface of glassy carbon electrode, and deposited gold nanoparticles with average size of about 100nm uniformly distributed on the surface of Ch. Moreover, the modified electrode exhibits strong electrochemical catalytic activity toward the oxidation of dopamine (DA), ascorbic acid (AA) and uric acid (UA) with obviously reduction of overpotentials. For the ternary mixture containing DA, AA and UA, these three compounds can be well separated from each other, allowing simultaneously determination of DA and UA under coexistence of AA. The proposed method can be applied to detect DA and UA in real samples with satisfactory results.
通过使用涂有金纳米颗粒/胆碱（GNP/Ch）的玻碳电极（GCE）构建了一种新型电化学传感器。采用电化学阻抗谱（EIS）、场发射扫描电子显微镜（SEM）和X射线光电子能谱（XPS）对该修饰电极的性能进行了表征。结果表明，胆碱共价键合在玻碳电极表面，平均粒径约为100nm的沉积金纳米颗粒均匀分布在胆碱表面。此外，修饰电极对多巴胺（DA）、抗坏血酸（AA）和尿酸（UA）的氧化表现出很强的电化学催化活性，过电位明显降低。对于含有DA、AA和UA的三元混合物，这三种化合物可以很好地相互分离，从而在AA共存的情况下同时测定DA和UA。该方法可用于实际样品中DA和UA的检测，结果令人满意。
