title: Three-dimensional graphene aerogel-supported iron oxide nanoparticles as an efficient adsorbent for magnetic solid phase extraction of organophosphorus pesticide residues in fruit juices followed by gas chromatographic determination.
abstract: In this research, a magnetic three dimensional-graphene nanocomposite (3D-G-Fe3O4) was prepared, characterized and used as an effective nanoadsorbent in magnetic solid-phase extraction (MSPE) of eight organophosphorus pesticides (OPPs) from juice samples prior to gas chromatography-nitrogen phosphorous detection (GC-NPD). The properties and morphology of 3D-G-Fe3O4 were characterized by scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR) and vibrating sample magnetometry (VSM). The main experimental parameters affecting extraction recoveries including extraction time, amount of adsorbent, pH of sample solution, salt concentration and desorption conditions were carefully studied and optimized. The results showed wide linear concentration ranges with determination coefficients between 0.9973 and 0.9999. The limits of detection (S/N=3) of the method and limits of quantification (S/N=10) were from 1.2 to 5.1 ng L(-1) and 3.4-17.0 ng L(-1), respectively. The intra-day and inter-day RSDs were 2.6-5.1% and 3.5-6.9%, respectively. The method was successfully applied to the analysis of OPPs in fruit juices (apple, orange, grape, sour-cherry and apricot) with recoveries in range of 86.6-107.5%. The GC-NPD results were confirmed by gas chromatography-mass spectrometry (GC-MS). The results demonstrated that with combination of highly interconnected 3D network structure and magnetism property of adsorbent, 3D-G-Fe3O4 aerogel exhibited exceptional extraction ability towards the OPPs.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Tehran, Tehran, Iran.
authors.forename: Shokouh
authors.initials: S
authors.lastname: Mahpishanian
authors.affiliation: Department of Chemistry, Faculty of Science, University of Tehran, Tehran, Iran. Electronic address: sereshti@khayam.ut.ac.ir.
authors.forename: Hassan
authors.initials: H
authors.lastname: Sereshti
mesh_terms: D002849:Chromatography, Gas; D004785:Environmental Pollutants / Q000032:analysis; D005290:Ferric Compounds; D005504:Food Analysis / Q000379:methods*; D000067030:Fruit and Vegetable Juices / Q000032:analysis*; D006108:Graphite / Q000737:chemistry; D008280:Magnetics; D027845:Malus / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis* / Q000302:isolation & purification; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D004785:Environmental Pollutants; D005290:Ferric Compounds; D010573:Pesticide Residues; C000499:ferric oxide; D006108:Graphite
keywords: Fruit juice; Gas chromatography; Magnetic solid phase extraction; Magnetic three-dimensional graphene; Organophosphorus pesticides