title: Comparison between solid-phase extraction methods for the chromatographic determination of organophosphorus pesticides in water.
abstract: A solid-phase microextraction (SPME) procedure has been developed to extract eight organophosphorus pesticides (OPs) in water and the method was compared with a conventional solid phase extraction (SPE) technique. The extracted OPs were analyzed by gas chromatography using thermionic specific detection. Both extraction methods presented linear calibration at least over the concentration range investigated (100 to 1000 ng x mL(-1) for SPE and 1 to 100 ng x mL(-1) for SPME). SPME method presented higher sensitivity than SPE. The quantitation limits were between 0.1 to 1.0 ng x mL(-1) for SPME depending upon the analyte, and 100 ng x mL(-1) for SPE. The precision, as measured by the standard deviations (RSD), were in the range 3.6% to 5.8% for SPME and 2.4% to 9.2% for SPE. Along with the feature of being a solvent - free sampling technique, SPME offers additional benefits due to its high sensitivity, simplicity, and small size sample required (typically: SPE - 500 mL, SPME - 5 mL).
authors.affiliation: University of Ribeirão Preto, Department of Pharmaceutical Sciences, SP, Brasil.
authors.forename: M E
authors.initials: ME
authors.lastname: Queiroz
authors.forename: S M
authors.initials: SM
authors.lastname: Silva
authors.forename: D
authors.initials: D
authors.lastname: Carvalho
authors.forename: F M
authors.initials: FM
authors.lastname: Lanças
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D007306:Insecticides / Q000032:analysis* / Q000302:isolation & purification; D009943:Organophosphorus Compounds; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D007306:Insecticides; D009943:Organophosphorus Compounds; D014874:Water Pollutants, Chemical