Ionic liquid-based graphene oxide-coated fiber for headspace-solid phase microextraction of polycyclic aromatic hydrocarbons in water samples

Ionic liquid (IL) containing amino and vinyl terminated imidazolium cation and bis[(trifluoromethyl)sulfonyl] imide anion-functionalized graphene oxide (GO) coating material was prepared and coated on a stainless steel wire by a sol-gel technique for headspace-solid phase microextraction (HS-SPME). Its extraction performance was checked by HS-SPME of polycyclic aromatic hydrocarbons (PAHs) coupled to gas chromatography with mass spectrometry (GC-MS). The extraction capability of the IL-functionalized GO-coated fiber was comparable with that of the commercial fibers of polydimethylsiloxane (PDMS) and polydimethylsiloxane/carboxen/divinylbenzene (PDMS/CAR/DVB). Under the optimized conditions, such as extraction temperature, extraction time, and salting-out, the proposed HS-SPME-GC-MS method presented a wide working range from 0.003 to 40 mu g L-1 with a correlation coefficient higher than 0.996, low detection limits from 1 to 5 ng L-1, and good precision less than 7%. The fiber-to-fiber repeatability was in the range of 0.2%-6.9%. The recoveries for 8 PAHs using the novel and commercial fibers in tap and seawater samples were obtained very close to each other and were in the range of 75.4% to 116.0%.