An electrochemical sensor for the determination of phoxim based on a graphene modified electrode and molecularly imprinted polymer

作者：Tan, Xuecai^*; Wu, Jiawen; Hu, Qi; Li, Xiaoyu; Li, Pengfei; Yu, Huicheng; Li, Xiaoyan; Lei, Fuhou

来源：Analytical Methods, 2015, 7(11): 4786-4792.

DOI：10.1039/c5ay00945f

Graphene and a novel cross-linker (ethylene glycol maleic rosinate acrylate) for preparing highly sensitive, molecularly imprinted sensors were proposed for phoxim determination. A molecularly imprinted polymer (MIP) film was created on a graphene-modified electrode for the determination of phoxim using a free radical polymerization method. The electrochemical properties of the MIP and non-molecularly imprinted polymer (NIP) sensors were investigated via cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The surface morphology of the imprinted film was characterized by scanning electron microscopy (SEM). Under the optimal experimental conditions, the peak currents were proportional to the concentrations of phoxim in the range of 8.0 x 10(-7) to 1.4 x 10(-4) mol L-1 with a detection limit of 2.0 x 10(-8) mol L-1 (S/N = 3). The imprinted electrochemical sensor was employed to determine phoxim in cucumber samples with recovery ranging from 98.06% to 101.13%. An adsorption model for the imprinted sensor was investigated, and the measured imprinting factor beta of the sensor was found to be 7.23, with the binding rate constant k being 14.2247 s. The developed electrochemical sensor based on the graphene modified electrode and the molecularly imprinted polymer exhibited good repeatability and stability, and can be successfully used to determine phoxim in cucumber samples.

• 出版日期2015
• 单位广西民族大学