A molecularly imprinted electrochemical sensor based on sol-gel technology and multiwalled carbon nanotubes-Nafion functional layer for determination of 2-nonylphenol in environmental samples

In this work, we have proposed a sensitive and selective detection technique for 2-nonylphenol (2-NP) based on the differential pulse voltammetry at a molecularly imprinted film on a glassy carbon electrode (GCE). The imprinted film was immobilised on the GCE by electrodeposition of a molecularly imprinted polymer (MIP) sol-gel consisting of a multiwalled carbon nanotube (MWNT)-Nafion (NF) composite. The modification procedure was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM). The recognition between MIP sol-gel film and target molecule was observed by measuring the change in DPV response of the oxidation-reduction probe, K3Fe(CN)(6) on GCE. Under optimized operational conditions, a linear response was obtained covering the concentration range from 0.2 to 360 mu mol L-1 with a detection limit of 0.06 mu mol L-1. The proposed sensor was applied to 2-NP determination in water and soil samples with the recoveries from 95.4 to 98.1%, showing a promising potential application in environment samples. Additionally, The imprinted sensor demonstrated higher affinity for target 2-NP than that of non-imprinted polymer (NIP) sensor. (C) 2013 Elsevier B.V. All rights reserved.