title: Sub- and supercritical fluid extraction of trichloropyridinol from soil prior to immunoassay.
abstract: A comparative study on the extraction of TCP (3,5,6-trichloro-2-pyridinol, a metabolite of chlorpyrifos) from soil with CO2 and H2O is reported. The polarity of the analyte requires the presence of both a cosolvent (methanol) and an ion-pair reagent [(1R)-(-)-10-camphorsulfonic acid ammonium salt] for 95% extraction in 30 min when supercritical CO2 at 40 degrees C and 383 bar is used as extractant. Subcritical water (250 degrees C and 200 bar) enables complete extraction within 15 min without additives. Quantitation of the target analyte is performed by specific immunoassay using a non-commercial monoclonal antibody which provides a linear determination range between 0.005 and 5 micrograms/g, with coefficients of variation of 5.3 and 4.9% for the SC-CO2 and sub-H2O extractions, respectively.
authors.affiliation: Department of Analytical Chemistry, Faculty of Sciences, University of Córdoba, Spain.
authors.forename: M M
authors.initials: MM
authors.lastname: Jiménez-Carmona
authors.forename: J J
authors.initials: JJ
authors.lastname: Manclús
authors.forename: A
authors.initials: A
authors.lastname: Montoya
authors.forename: M D
authors.initials: MD
authors.lastname: Luque de Castro
mesh_terms: D002849:Chromatography, Gas / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D006358:Hot Temperature; D011312:Pressure; D011728:Pyridones / Q000032:analysis*; D015203:Reproducibility of Results; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D011728:Pyridones; D012989:Soil Pollutants; C012587:3,5,6-trichloro-2-pyridinol