Fei Junjie, Peng Yan, Tan Hongyan, Chen Xiaoming, Yang Jing, Li Junan
College of Chemistry, Key Laboratory of Advanced Materials and Rheological Properties of Ministry of Education, Xiangtan University, Xiangtan 411105, Hunan, P.R. China.
Bioelectrochemistry. 2007 May;70(2):369-74. doi: 10.1016/j.bioelechem.2006.05.007. Epub 2006 May 23.
A sensitive electrochemical method was developed for the differential pulse voltammetric determination of rhein at a glassy carbon electrode (GCE) modified with a nanoparticle composite film. In the present paper, multi-wall carbon nanotube (MWNT) was dispersed into dihexadecyl phosphate (DHP) to give a homogeneous suspension. After the solvent evaporation, a uniform film of MWNT-DHP composite film was obtained on the GCE surface. The MWNT-DHP composite film-modified GCE exhibited excellent electrocatalytic behavior toward the redox of rhein. Compared with an irreversible reduction of rhein at the bare GCE, a reversible redox behavior of rhein was observed at the MWNT-DHP composite film-modified GCE and the redox current was also enhanced greatly. Based on this, a cathodic differential pulse voltammetry (DPV) was applied for the determination of rhein. The experimental parameters, which influence the current of rhein, were optimized. Under optimal conditions, the cathodic DPV measurements were performed and a linear response of rhein was obtained in the range from 1.0 x 10(-8) to 5.0 x 10(-6) mol L(-1) and with a limit of detect (LOD) of 5.0 x 10(-9) mol L(-1). The proposed procedure was successfully applied to assay rhein in real samples with satisfactory results.
开发了一种灵敏的电化学方法，用于在纳米颗粒复合膜修饰的玻碳电极（GCE）上差分脉冲伏安法测定大黄酸。在本文中，将多壁碳纳米管（MWNT）分散到磷酸二己酯（DHP）中，得到均匀的悬浮液。溶剂蒸发后，在GCE表面获得了MWNT-DHP复合膜的均匀薄膜。MWNT-DHP复合膜修饰的GCE对大黄酸的氧化还原表现出优异的电催化行为。与大黄酸在裸GCE上的不可逆还原相比，在MWNT-DHP复合膜修饰的GCE上观察到大黄酸的可逆氧化还原行为，并且氧化还原电流也大大增强。基于此，采用阴极差分脉冲伏安法（DPV）测定大黄酸。优化了影响大黄酸电流的实验参数。在最佳条件下进行阴极DPV测量，大黄酸在1.0×10（-8）至5.0×10（-6）mol L（-1）范围内获得线性响应，检测限（LOD）为5.0×10（-9）mol L（-1）。所提出的方法成功应用于实际样品中大黄酸的测定，结果令人满意。
