Xi Lingling, Wang Fengli, Zhu Zuoyi, Huang Zhongping, Zhu Yan
Department of Chemistry, Xixi Campus, Zhejiang University, Hangzhou 310028, China.
Department of Chemistry, Xixi Campus, Zhejiang University, Hangzhou 310028, China.
Talanta. 2014 Feb;119:440-6. doi: 10.1016/j.talanta.2013.11.024. Epub 2013 Nov 19.
A novel Cu nanoparticles/reduced graphene oxide-chitosan (CuNPs/r-GO-chitosan) composite film modified glassy carbon electrode (GCE) was fabricated by dispersing CuNPs uniformly on a stable r-GO-chitosan thin film through electrodeposition process. The modified electrode was characterized by cyclic voltammetry, scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS), and exhibited efficiently electrocatalytic oxidation toward monosaccharides with high stability. The good electrocatalytic activity of this modified electrode might be attributed to the synergistic effect of r-GO and CuNPs, and the stability might be attributed to the r-GO and chitosan thin matrix film. When the CuNPs/r-GO-chitosan/GCE was used as an electrochemical sensor in high performance anion exchange chromatography-direct current amperometric detection (HPAEC-DC) flowing system for the determination of monosaccharides under constant working potential of +0.55 V, the detection limits (S/N=3) ranged from 0.006 to 0.02 mg L(-1) for the analyzed sugars, and the dynamic linear ranges spanned from 0.02 to 500 mg L(-1). The proposed method has been applied for the determination of monosaccharide composition of crude polysaccharides from phellinus igniarius real samples, and the results were satisfactory.
通过电沉积过程将铜纳米颗粒（CuNPs）均匀分散在稳定的还原氧化石墨烯-壳聚糖（r-GO-壳聚糖）薄膜上，制备了一种新型的铜纳米颗粒/还原氧化石墨烯-壳聚糖（CuNPs/r-GO-壳聚糖）复合膜修饰玻碳电极（GCE）。采用循环伏安法、扫描电子显微镜（SEM）和电化学阻抗谱（EIS）对修饰电极进行了表征，结果表明该修饰电极对单糖具有高效的电催化氧化性能且稳定性高。这种修饰电极良好的电催化活性可能归因于r-GO和CuNPs的协同效应，而稳定性可能归因于r-GO和壳聚糖的薄膜基体。当将CuNPs/r-GO-壳聚糖/GCE用作高效阴离子交换色谱-直流安培检测（HPAEC-DC）流动体系中的电化学传感器，在+0.55 V的恒定工作电位下测定单糖时，所分析糖类的检测限（S/N=3）为0.006至0.02 mg L⁻¹，动态线性范围为0.02至500 mg L⁻¹。该方法已应用于桑黄实际样品中粗多糖单糖组成的测定，结果令人满意。
