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PubMed · 14763740

Ionic liquid-based liquid-phase microextraction, a new sample enrichment procedure for liquid chromatography.

Jing-fu Liu·Yu-guang Chi·Gui-bin Jiang·Chao Tai·Jin-feng Peng·Jing-Tian Hu
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Abstract

Room temperature ionic liquids (RTILs) were used as extraction solvent in liquid-phase microextraction (LPME) coupled with liquid chromatography. Using 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6MIM][PF6]) as extraction solvent, some parameters related to LPME of 4-nonylphenol (4-NP) and 4-tert-octylphenol (4-t-OP) were optimized. Although [C6MIM][PF6] can suspend a much larger volume of drop on the needle of the microsyringe than the conventional solvents such as 1-octanol and carbon tetrachloride, the method sensitivity was analyte dependent because of the different partition coefficients and the relatively large viscosity of [C6MIM][PF6]. The proposed procedure has a detection limit and enrichment factor of 0.3 microg l(-1) and 163 for 4-NP, and 0.7 microg l(-1) and 130 for 4-t-OP, respectively. Aqueous samples including tap water, river water, and effluent from sewage treatment plant were analyzed by the proposed method and the recoveries at 10 microg l(-1) spiked level were in the range of 90-113%.

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Chromatography, High Pressure LiquidIonsIsoelectric FocusingReproducibility of ResultsSensitivity and SpecificitySolventsSpecimen HandlingTime FactorsWaterJournal ArticleResearch Support, Non-U.S. Gov't

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Jing-fu Liu, Yu-guang Chi, Gui-bin Jiang, Chao Tai, Jin-feng Peng, Jing-Tian Hu. 2004-02-13. Ionic liquid-based liquid-phase microextraction, a new sample enrichment procedure for liquid chromatography.. https://doi.org/10.1016/j.chroma.2003.11.005

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