Molecularly imprinted polymer grafted graphene for simultaneous electrochemical sensing of 4, 4-methylene diphenylamine and aniline by differential pulse voltammetry

A sensitive and selective electrochemical sensor based on molecular imprinting polymers grafted graphene (MIPs-G) was developed for simultaneous measurement of 4, 4-methylene diphenylamine (MDA) and aniline by differential pulse voltammetry (DPV). MIPs-G was synthesized via free radical polymerization reaction using MDA and 4-vinyl pyridine as template molecule and functional monomer respectively. The obtained nanocomposites were characterized by transmission electron microscope, scanning electron microscope, Fourier transform infrared spectrometry, Raman spectroscopy and thermal gravimetric analysis. After removal template molecules, MIPs-G was used as electrode material for aromatic amines measurements. Due to the high binding affinity towards MDA and the π-π interaction with aniline, the MIPs-G based electrochemical sensor can be used for simultaneous detection of MDA and aniline by DPV. Under the optimized condition, the oxidation potentials for MDA and aniline were observed at 0.62 and 0.72 V, respectively. Moreover, MIPs-G modified glassy carbon electrode shows linear response towards MDA and aniline simultaneously over the range of 1.0 to 15 μM. The MIPs-G based electrochemical sensor has been applied for simultaneous measurement of MDA and aniline in plastic tableware.