title: Water compatible stir-bar devices imprinted with underivatised glyphosate for selective sample clean-up.
abstract: This paper reports the development of stir bars with a new MIP based coating, for the selective sorptive extraction of the herbicide glyphosate (GLYP). Molecular imprinting of the polymer has directly been carried out employing underivatised GLYP as the template molecule. Due to the poor solubility of the target compound in organic solvents, the MIP methodology has been optimised for rebinding in aqueous media, being the synthesis and the rebinding steps carried out in water:methanol mixtures and pure aqueous media. The coating has been developed by radical polymerisation initiated by UV energy, using N-allylthiourea and 2-dimethyl aminoethyl methacrylate as functional monomers and ethylene glycol dimethacrylate as the cross-linker. Mechanical stability of the coating has been improved using 1,3-divinyltetramethyldisiloxane in the polymerisation mixture. Under the optimised conditions, the MIP has demonstrated excellent selectivity for the target compound in the presence of structural analogues, including its major metabolites. The applicability of the proposed method to real matrices has also been assessed using river water and soil samples. Registered mean recoveries ranged from 90.6 to 97.3% and RSD values were below 5% in all cases, what confirmed the suitability of the described methodology for the selective extraction and quantification of GLYP.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Gomez-Caballero
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain.
authors.forename: Goretti
authors.initials: G
authors.lastname: Diaz-Diaz
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain.
authors.forename: Olatz
authors.initials: O
authors.lastname: Bengoetxea
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain.
authors.forename: Amaia
authors.initials: A
authors.lastname: Quintela
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain.
authors.forename: Nora
authors.initials: N
authors.lastname: Unceta
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain.
authors.forename: M Aranzazu
authors.initials: MA
authors.lastname: Goicolea
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain. Electronic address: r.barrio@ehu.es.
authors.forename: Ramón J
authors.initials: RJ
authors.lastname: Barrio
mesh_terms: D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D006540:Herbicides / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D054802:Molecular Imprinting / Q000379:methods*; D009930:Organic Chemicals / Q000737:chemistry; D058105:Polymerization; D011108:Polymers / Q000737:chemistry; D045483:Rivers / Q000737:chemistry; D012833:Siloxanes / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry*; D000097797:Glyphosate
chemical_list: D005998:Glycine; D006540:Herbicides; D009930:Organic Chemicals; D011108:Polymers; D012833:Siloxanes; D012987:Soil; D012997:Solvents; D014867:Water; D000097797:Glyphosate; C528333:divinyltetramethyldisiloxane
keywords: Glyphosate; Natural waters; SBSE; Soils; Water compatible MIP