Composites of multiwalled carbon nanotubes/polyethyleneimine (MWCNTs/PEI) and molecularly imprinted polymers for dinitrotoluene recognition

In this work, a novel strategy for the imprinting of 2,4-dinitrotoluene (DNT) molecule on the surface of functionalized multiwalled carbon nanotubes/polyethyleneimine (Fun-MWCNTs/PEI) was proposed and developed to prepare a highly selective DNT-imprinted electrochemical sensor. The electrochemical characteristics of the fabricated Fun-MWCNTs/PEI-MIPs sensor were investigated by cyclic voltammetry and differential pulse voltammetry in detail. Experimental results demonstrated that the Fun-MWCNTs/PEI-MIPs modified electrode exhibited an excellent electrocatalytic activity to DNT and the current responses were found to be in a good linear range from 2.2 × 10^-9 mol/L to 1.0 × 10^-6 mol/L with the detection limit of 1.0 × 10^-9 mol/L (S/N = 3). Additionally, in comparison with other similar nitroaromatic compounds, a satisfactory selectivity toward DNT determination was also obtained due to the appearance of abundant effective imprinted sites at the surface or in the proximity of Fun-MWCNTs/PEI-MIPs films. In short, the surface molecular imprinted strategy presented in the current work developed a new way for the rapid, sensitive and selective measurement of trace DNT, which would exhibit a prospective in the on-line monitoring of nitroaromatic compounds (NACs) in the fields of industry and environmental monitoring.