title: Comparison of four mass analyzers for determining carbosulfan and its metabolites in citrus by liquid chromatography/mass spectrometry.
abstract: Four liquid chromatography/mass spectrometry (LC/MS) systems, equipped with single quadrupole, triple quadrupole (QqQ), quadrupole ion trap (QIT) and quadrupole time-of-flight (QqTOF) mass analyzers, were evaluated for the analysis of carbosulfan and its main transformation products. The comparison of quantitative aspects (sensitivity, precision and accuracy) was emphasized. Results showed that the triple quadrupole instrument reaches at least 20-fold higher sensitivity (LOD from 0.04 to 0.4 microg kg(-1)) compared to the single quadrupole (4-70 microg kg(-1)), the QIT (4-25 microg kg(-1)) and the QqTOF (4-23 microg kg(-1)) instruments. Recoveries were over 70% for all the analytes, except dibutylamine and 7-phenolcarbofuran. Repeatabilities (within-day) were slightly better by the single quadrupole (5-10%) and the QqQ (5-9%) than by the QIT (12-16%) and the QqTOF (9-16%). Both the QqTOF and QIT offer a linear dynamic range of two orders of magnitude whereas the single quadrupole and QqQ of, at least, three orders of magnitude. The method was applied to analyze carbosulfan field-treated orange samples, in which carbosulfan, carbofuran, 3-hydroxycarbofuran, and dibutylamine were found. As an example, the mean carbosulfan concentration was 20 +/- 0.6 microg kg(-1) measured by the QqQ, 22 +/- 1.2 microg kg(-1) by the single quadrupole, 25 +/- 2.8 microg kg(-1) by the QIT, and 20 +/- 1.8 microg kg(-1) by the QqTOF. Although the QqQ is more sensitive and precise, the mean values obtained by the four instruments are acceptable and comparable. The potential of each technique for the verification of the identity of residues detected in oranges is discussed using the concept of identification points.
authors.affiliation: Laboratori de Bromatologia i Toxicologia, Facultat de Farmàcia, Universitat de València, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Spain. Coler.Soler@uv.es
authors.forename: Carla
authors.initials: C
authors.lastname: Soler
authors.forename: Brett
authors.initials: B
authors.lastname: Hamilton
authors.forename: Ambrose
authors.initials: A
authors.lastname: Furey
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: James
authors.forename: Jordi
authors.initials: J
authors.lastname: Mañes
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Picó
mesh_terms: D002082:Butylamines / Q000032:analysis / Q000378:metabolism; D002219:Carbamates / Q000032:analysis* / Q000378:metabolism; D002235:Carbofuran / Q000031:analogs & derivatives / Q000032:analysis / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D032084:Citrus sinensis / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation* / Q000379:methods
chemical_list: D002082:Butylamines; D002219:Carbamates; C045274:dibutylamine; C028403:3-hydroxycarbofuran; D002235:Carbofuran; C035038:carbosulfan