A new disposable ionic liquid based coating for headspace solid-phase microextraction of methyl tert-butyl ether in a gasoline sample followed by gas chromatography–flame ionization detection

A new ionic liquid (IL) based solid-phase microextraction (SPME) fiber was investigated and used for headspace (HS) extraction of methyl tert-butyl ether (MTBE) in a gasoline sample. Using the new IL coated HS-SPME fiber with the combination of gas chromatography–flame ionization detection (GC–FID); sub-to-low μg L−1 concentrations of MTBE were detected. Four different ILs including 1-butyl-3-methylimidazolium tetraflouroborate ([C4C1IM] [BF4]), 1-octyl-3-methylimidazolium tetraflouroborate ([C8C1IM] [BF4]), 1-octyl-3-methylimidazolium hexaflourophosphate ([C8C1IM] [PF6]) and 1-ethyl-3-methylimidazolium ethylsulphate ([C2C1IM] [ETSO4]) were synthesized and examined for extraction, preconcentration and determination of MTBE. It was observed that [C8C1IM] [BF4] showed the highest extraction efficiency and possessed the best extractability for MTBE. The fiber coating takes up the compounds from the sample by absorption in the case of liquid coatings. The calibration graph was linear in a concentration range of 1–120 μg L−1 (R2 > 0.994) with the detection limit of 0.09 μg L−1 level. The new IL-coated fiber was applied successfully for the determination of MTBE in a gasoline sample with good recoveries between 90 and 95%.