title: Liquid-liquid extraction/headspace/gas chromatographic/mass spectrometric determination of benzene, toluene, ethylbenzene, (o-, m- and p-)xylene and styrene in olive oil using surfactant-coated carbon nanotubes as extractant.
abstract: BTEX-S compounds are widely distributed in the environment and can be present in different foodstuffs, including olive oil. Taking into account the risks of the exposure to these compounds, analytical methods for their determination in different matrices are mandatory. In this paper, the use of surfactant-coated multiwalled carbon nanotubes as additive in liquid-liquid extraction is applied for the determination of single-ring aromatic compounds in olive oil samples. After sample treatment, the aqueous extracts are subsequently analyzed by headspace/gas chromatography/mass spectrometry allowing the determination of BTEX-S within ca. 15 min. Each stage of the proposed LLE/HS/GC/MS configuration involves a selectivity enhancement avoiding the interference of other compounds of the sample matrix. Limits of detection were in the range 0.25 ng mL(-1) (obtained for ethylbenzene) and 0.43 ng mL(-1) (for benzene). The repeatability of the proposed method expressed as RSD varied between 1.9% (styrene) and 3.3% (benzene) (n=11).
authors.affiliation: Department of Analytical Chemistry, Marie Curie Building (Annex), Campus de Rabanales, University of Cordoba, E-14071 Cordoba, Spain.
authors.forename: Carolina
authors.initials: C
authors.lastname: Carrillo-Carrión
authors.forename: Rafael
authors.initials: R
authors.lastname: Lucena
authors.forename: Soledad
authors.initials: S
authors.lastname: Cárdenas
authors.forename: Miguel
authors.initials: M
authors.lastname: Valcárcel
mesh_terms: D001554:Benzene / Q000302:isolation & purification; D001555:Benzene Derivatives / Q000302:isolation & purification; D005591:Chemical Fractionation / Q000295:instrumentation* / Q000379:methods; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006841:Hydrocarbons, Aromatic / Q000145:classification / Q000302:isolation & purification*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D000069463:Olive Oil; D010938:Plant Oils / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020058:Styrene / Q000302:isolation & purification; D013501:Surface-Active Agents / Q000737:chemistry*; D014050:Toluene / Q000302:isolation & purification; D014992:Xylenes / Q000302:isolation & purification
chemical_list: D001555:Benzene Derivatives; D006841:Hydrocarbons, Aromatic; D037742:Nanotubes, Carbon; D000069463:Olive Oil; D010938:Plant Oils; D013501:Surface-Active Agents; D014992:Xylenes; D014050:Toluene; D020058:Styrene; D001554:Benzene; C004912:ethylbenzene