Isoproturon (IPU) Electrochemical Sensing Based on a Polymethylmethacrylate Ferrite (PMMA/M(FexOy)) Nanocomposite Modified Electrode

The use of pesticides has been increased in recent years, to enhance crops productivity, which may lead to a serious global concern of environmental pesticides monitoring. Isoproturon (IPU: 3-(4-isopropylphenyl)-1,1-dimethylurea) is an herbicide widely used in wheat crops. However, when it enters in the ecosystem, it is heavily toxic to humans. Thus, there is an urgent need to develop sensitive and selective IPU detection methods. In the present work, a novel polymethylmethacrylate/ferrite (PMMA/M(FexOy)) polymer nanocomposite (PNC) modified glassy carbon electrode (GCE) was developed for IPU detection. The PNC/GCE surface morphology was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). PNC electrochemical characterization (EC) was performed by cyclic voltammetry (CV) that showed a quasi-reversible redox behavior. PNC/GCE demonstrated an excellent square wave voltammetric (SWV) response towards IPU, with a limit of quantification (LOQ) of 1.98 x 10(-7) M, and a limit of detection (LOD) of 6.5 x 10(-8) M, in 1 M HClO4 (perchloric acid), at pH 2.0. EC investigations reflected a peak current that was linearly related to IPU concentrations, with a high detection sensitivity. It also showed much better CV and SWV IPU responses than those of a bare GCE, and further environmental stability, without a high influence of common interfering ions.