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Abstract: 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 360μmolL −1 with a detection limit of 0.06μmolL −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. [Copyright &y& Elsevier]

A novel electrochemical sensor based on molecularly imprinted polymer membranes (MIPM) as biomimetic molecular recognition element involved in o -aminothiophenol functionalized Au nanoparticles (ATP@AuNPs) modified gold electrode was constructed for sensitive and selective detection of herbicide simazine (SMZ). The nano-scaled MIPM, with high specific surface area, was prepared by self-assembly of o -aminothiophenol (ATP) and electrodeposition of ATP@AuNPs in the presence of template SMZ. Cathodic current of SMZ was measured by cyclic voltammetry and the results exhibited that the proposed sensor possess a high electrocatalytic activity at a negative potential and a fast rebinding dynamics towards the reduction of SMZ in 0.01 M H 2 SO 4 solution (pH 1.7). Linear dependency of peak current on SMZ concentrations was observed from 0.03 to 140 μM and detection limit was estimated to be 0.013 μM (3S/N). The enhancement of sensitivity was attributed to the presence of gold nanoparticles (AuNPs) which decreased the electron-transfer impedance and increased imprinting sites, lead to the superior enrichment effect of the trace amount of SMZ in aqueous solvent. The developed SMZ imprinted sensor exhibited excellent long-term stability and acceptable repeatability. In addition, the proposed method was successfully applied to measure SMZ in several real samples with the spiked recoveries changing from 91.4% to 96.8%, showing a promising potential in practical application. [ABSTRACT FROM AUTHOR]