Determination of imidacloprid and its metabolite 6-chloronicotinic acid in greenhouse air by application of micellar electrokinetic capillary chromatography with solid-phase extraction.
A method is described for the analysis of the insecticide imidacloprid [1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] and its metabolite 6-chloronicotinic acid by micellar electrokinetic chromatography with diode-array detection at 270 and 227 nm, respectively. The best results were obtained using sodium dodecyl sulphate at a concentration of 60 mM and a running buffer of NH4Cl/NH3 at 15 mM (pH 8.5). The selection of instrumental parameters such as voltage at 30 kV with an injection time of 20 s gave the best resolution with an analysis time of less than 6 min. The method yields similar sensitivity for the parent compound and for the metabolite, with detection limits of 0.71 and 1.18 microg/ml for imidacloprid and 6-chloronicotinic acid, respectively. The sampling and analysis of these two pesticides in greenhouse air was carried out using personal samplers connected to XAD-2 cartridges as sampling media, investigating the dissipation of analytes in a 24-h period after their application.
Segura Carretero
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Department of Analytical Chemistry, Faculty of Sciences, University of Granada, 18071 Granada, Spain. ansegura@ugr.es
Cruces-Blanco
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Pérez Durán
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Fernández Gutiérrez
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D000383:Agriculture / Q000379:methods; D000388:Air / Q000032:analysis*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D007093:Imidazoles / Q000032:analysis*; D007306:Insecticides / Q000032:analysis*; D000073943:Neonicotinoids; D009539:Nicotinic Acids / Q000032:analysis*; D009574:Nitro Compounds; D010944:Plants; D011786:Quality Control; D012680:Sensitivity and Specificity
D007093:Imidazoles; D007306:Insecticides; D000073943:Neonicotinoids; D009539:Nicotinic Acids; D009574:Nitro Compounds; C082359:imidacloprid; C035953:6-chloronicotinic acid