Abstract

An electrochemical sensor for the determination of p-nitrophenol (p-NP) was developed based on a molecularly imprinted polymer (MIP) on graphene oxide (GO). The sensor was prepared via precipitation polymerization of aniline and ammonium persulfate as the host molecule and initiator. The morphologies and electrochemical behavior of the imprinted sensor were characterized by Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), field emission electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS) and cyclic voltammetry techniques. The electrochemical investigations were conducted by screening the effects of pH, p-NP concentration and scan rate. Under the optimized experimental conditions, the oxidation peak current varies linearly with p-NP concentration, in the range 6 × 10−5–14 × 10−5 mol/L with a detection limits of 2 × 10−5 mol/L (correlation coefficient of 0.991). The electrochemical sensor was also used to detect p-NP in tap water, where it shows the excellent recoveries. Moreover, the sensor probe revealed an excellent selectivity for p-NP compared to other phenol derivatives. This proposed sensor was used successfully for determination of spiked p-nitrophenol in water samples.