title: Development of surface imprinted core-shell nanoparticles and their application in a solid-phase dispersion extraction matrix for methyl parathion.
abstract: Applying molecular imprinting techniques to the surface of functionalized SiO2 allows the preparation of molecularly imprinted polymers (MIPs) with accessible, high affinity and surface exposed binding sites. This paper demonstrates a new strategy for producing such hybrid organic-inorganic surface imprinted silica nanoparticles for specific recognition of methyl parathion. The technique provides surface grafting imprinting in chloroform using amino modified silica nanoparticles as supports, acrylamide as the functional monomer, γ-methacryloxypropyl trimethoxy silane as the grafting agent, and methyl parathion as a template. The amino propyl functional monomer layer directs the selective occurrence of imprinting polymerization at the silica surface through copolymerization of grafting agents with functional monomers, but also acts as an assistive monomer to drive the template into the formed polymer shells to create effective recognition sites. The resulting MIPs-SiO2 nanoparticles display three-dimensional core-shell architectures and large surface areas. The molecularly imprinted shell provides recognition sites for methyl parathion, with the materials exhibiting excellent performance for selecting the template. Using MIPs-SiO2 nanoparticles as a matrix of solid-phase dispersion extraction sorbents, trace amounts of methyl parathion are selectivity extracted from pear and green vegetable samples while simultaneously eliminating matrix interferences, attaining recoveries of 84.7-94.4% for the samples.
authors.affiliation: Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Department of Chemistry, South China Normal University, Guangzhou 510006, China; Guangzhou Center for Disease Control and Prevention, Guangzhou 510440, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Tan
authors.affiliation: Guangdong Key Laboratory of Green Processing of Natural Products and Product Safety, School of Light Industry and Food Science, South China University of Technology, Guangzhou 510641, China.
authors.forename: Weiming
authors.initials: W
authors.lastname: Li
authors.affiliation: Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Department of Chemistry, South China Normal University, Guangzhou 510006, China.
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.affiliation: Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Department of Chemistry, South China Normal University, Guangzhou 510006, China. Electronic address: tanglab@scnu.edu.cn.
authors.forename: Youwen
authors.initials: Y
authors.lastname: Tang
mesh_terms: D004785:Environmental Pollutants / Q000032:analysis / Q000302:isolation & purification*; D007306:Insecticides / Q000032:analysis / Q000302:isolation & purification*; D008743:Methyl Parathion / Q000032:analysis / Q000302:isolation & purification*; D054802:Molecular Imprinting; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011108:Polymers / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D004785:Environmental Pollutants; D007306:Insecticides; D011108:Polymers; D008743:Methyl Parathion; D012822:Silicon Dioxide
keywords: Core–shell nanoparticles; Methyl parathion; Molecularly imprinted; Solid-phase dispersion extraction