title: Extraction and preconcentration of organophosphorus pesticides in water by using a polymethacrylate-based sorbent modified with magnetic nanoparticles.
abstract: A polymethacrylate-based sorbent modified with magnetic nanoparticles (MNPs) has been synthesized and used as sorbent for solid-phase extraction (SPE) and magnetic solid-phase extraction (MSPE) of three organophosphorus pesticides (phosmet, pirimiphos-methyl, and chlorpyrifos) in water samples followed by high-performance liquid chromatography-diode array detection. The sorbent was prepared from a glycidyl methacrylate-based polymer, modified with a silanizing agent, followed by immobilization of MNPs on the surface of the material. The sorbent was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Comparative studies of this support were done both in conventional SPE cartridge and MSPE approach. Several extraction parameters (loading pH, elution solvent, eluting volume, and loading flow rate) were investigated in detail. Under optimal conditions, the proposed sorbent gave an excellent enrichment efficiency of analytes and detection limits between 0.01 and 0.25 μg L-1. The recoveries of organophosphorus pesticides in spiked water samples were in the range of 71-98%, and the developed sorbent showed a high reusability (up to 50 uses without losses in recovery). The proposed method was satisfactorily applied to the analysis of these pesticides in water samples from different sources.
authors.affiliation: Instituto de Investigación para la Gestión Integrada de Zonas Costeras, Universitat Politècnica de València, C/Paranimf 1, 46730, Grao de Gandía, Spain. sumello@qim.upv.es.
authors.forename: Susana
authors.initials: S
authors.lastname: Meseguer-Lloret
authors.affiliation: Instituto de Investigación para la Gestión Integrada de Zonas Costeras, Universitat Politècnica de València, C/Paranimf 1, 46730, Grao de Gandía, Spain.
authors.forename: Sagrario
authors.initials: S
authors.lastname: Torres-Cartas
authors.affiliation: Instituto de Investigación para la Gestión Integrada de Zonas Costeras, Universitat Politècnica de València, C/Paranimf 1, 46730, Grao de Gandía, Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: Catalá-Icardo
authors.affiliation: Department of Analytical Chemistry, University of Valencia, C/Doctor Moliner 50, Burjassot, 46100, Valencia, Spain.
authors.forename: Ernesto F
authors.initials: EF
authors.lastname: Simó-Alfonso
authors.affiliation: Department of Analytical Chemistry, University of Valencia, C/Doctor Moliner 50, Burjassot, 46100, Valencia, Spain. jmherrer@uv.es.
authors.forename: José M
authors.initials: JM
authors.lastname: Herrero-Martínez
keywords: Magnetic polymer-based material; Organophosphorus pesticides; Solid-phase extraction; Water analysis