title: Ionic liquid supported three-phase liquid-liquid-liquid microextraction as a sample preparation technique for aliphatic and aromatic hydrocarbons prior to gas chromatography-mass spectrometry.
abstract: For the first time hollow fiber-protected ionic liquid supported three-phase (liquid-liquid-liquid) microextraction (HFM-LLLME) was developed for the gas chromatography-mass spectrometric (GC-MS) analysis of aromatic and aliphatic hydrocarbons. The hydrocarbons were extracted from 10 ml of aqueous samples though small volumes of ionic liquid and organic solvent in the hollow fiber membrane HFM) wall and channel, respectively. The ionic liquid was immiscible with both the aqueous sample and the organic solvent (toluene). After extraction, the enriched solvent was directly injected into a GC-MS system for analysis without any further pretreatment. Ionic liquid supported HFM-LLLME shows better extraction performance than two-phase HFM-liquid-phase microextraction, in which only organic solvent is involved, and solid-phase microextraction. The ionic liquid and organic solvent combination found most suitable for HFM-LLLME was 1-butyl-3-methylimidazolium hexafluorophosphate, and toluene, respectively. This new technique provided up to 210-fold enrichment of aliphatic and aromatic hydrocarbons in 40 min with good reproducibility (<11%) and limits of detection (1-7 ng l(-1)).
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
authors.forename: Chanbasha
authors.initials: C
authors.lastname: Basheer
authors.forename: Anass Ali
authors.initials: AA
authors.lastname: Alnedhary
authors.forename: B S
authors.initials: BS
authors.lastname: Madhava Rao
authors.forename: Rajasekhar
authors.initials: R
authors.lastname: Balasubramanian
authors.forename: Hian Kee
authors.initials: HK
authors.lastname: Lee
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry; D006838:Hydrocarbons / Q000737:chemistry*; D052617:Solid Phase Microextraction / Q000379:methods*
chemical_list: D006838:Hydrocarbons