title: Zincon-immobilized silica-coated magnetic Fe3O4 nanoparticles for solid-phase extraction and determination of trace lead in natural and drinking waters by graphite furnace atomic absorption spectrometry.
abstract: A new protocol using zincon-immobilized silica-coated magnetic Fe(3)O(4) nanoparticles (Zincon-Si-MNPs) as solid-phase extraction (SPE) medium has been developed for the separation and preconcentration of trace lead in water. Various parameters such as pH, extraction time, concentration and volume of eluent, sample volume, and influence of co-existing ions have been investigated in order to establish the optimum conditions for the determination of lead in combination with graphite furnace atomic absorption spectrometry (GFAAS). The detection limit (LOD) of the proposed method for lead based on an enrichment factor of 200 was 10 ng L(-1). The relative standard deviations (RSDs, n=5) were 8.3%, 7.8% and 9.2%, respectively, at 5, 0.5 and 0.05 ng mL(-1) levels. This method has been successfully applied to the analysis of trace lead in natural and drinking water samples and the recoveries for the spiked samples were in the range of 84-104%.
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering and Center of Materials Analysis, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Hong-mei
authors.initials: HM
authors.lastname: Jiang
authors.forename: Zhong-peng
authors.initials: ZP
authors.lastname: Yan
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhao
authors.forename: Xin
authors.initials: X
authors.lastname: Hu
authors.forename: Hong-zhen
authors.initials: HZ
authors.lastname: Lian
mesh_terms: D060766:Drinking Water / Q000737:chemistry*; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D005410:Flame Ionization; D005562:Formazans / Q000737:chemistry*; D006108:Graphite; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007854:Lead / Q000032:analysis*; D057230:Limit of Detection; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D012822:Silicon Dioxide / Q000737:chemistry*; D052616:Solid Phase Extraction; D013054:Spectrophotometry, Atomic; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D060766:Drinking Water; D005562:Formazans; D058185:Magnetite Nanoparticles; D014874:Water Pollutants, Chemical; D007854:Lead; C009809:2-carboxy-2'-hydroxy-5'-sulfoformazylbenzene; D012822:Silicon Dioxide; D006108:Graphite; D052203:Ferrosoferric Oxide