Molecularly imprinted electrochemical sensor based on amine group modified graphene covalently linked electrode for 4-nonylphenol detection

In this work, an imprinted electrochemical sensor based on electrochemical reduced graphene covalently modified carbon electrode was developed for the determination of 4-nonylphenol (NP). An amine-terminated functional graphene oxide was covalently modified onto the electrode surface with diazonium salt reactions to improve the stability and reproducibility of the imprinted sensor. The electrochemical properties of each modified electrodes were investigated with differential pulse voltammetry (DPV). The electrochemical characteristic of the imprinted sensor was also investigated using electrochemical impedance spectroscopy (EIS) in detail. The response currents of the imprinted electrode exhibited a linear relationship toward 4-nonylphenol concentration ranging from 1.0×10−11 to 1.0×10−8 g mL−1 with the detection limit of 3.5×10–12 g mL−1 (S/N=3). The fabricated electrochemical imprinted sensor was successfully applied to the detection of 4-nonylphenol in rain and lake water samples.