Determination of Polycyclic Aromatic Hydrocarbons in Tobacco Smoke by Ionic Liquid Enrichment and Gas Chromatography – Mass Spectrometry

ABSTRACT

A rapid, efficient and environmentally friendly method based on the ionic liquid (IL) 1-hexyl-3-methylimidazolium hexafluorophosphate ([C₆MIM][PF₆]) was developed for the determination of 16 polycyclic aromatic hydrocarbons (PAHs) in mainstream tobacco smoke. This technique combined ionic liquid (IL) enrichment with solvent reverse extraction for the replacement of solid phase extraction and rotary evaporation in the traditional method and enriched PAHs in the organic solvent. Several parameters, including the type of ionic liquid, volume of ionic liquid and water, extraction time, vortex time and reverse extraction time, were optimized. After pretreatment, the analytes were analyzed by gas chromatography-mass spectrometry (GC-MS) using selective ion monitoring (SIM). Satisfactory results were achieved when this method was applied to determine PAHs in mainstream tobacco smoke. The calibration curves were linear with correlation coefficients ranging from 0.9955 to 0.9999 at concentration levels of 10–800 µg L⁻¹, and the relative standard deviations of the optimized method were between 0.7% and 5.3%. The limits of detection were 0.01–0.6 ng cig⁻¹, and the recoveries of the compounds were 80.2–118%. A comparison of this protocol with literature methods demonstrated that the proposed procedure provides accurate and reliable sample-treatment for the determination of PAHs in tobacco samples.

KEYWORDS:

• Gas chromatography-mass spectrometry (GC-MS)
• ionic liquid (IL)
• polycyclic aromatic hydrocarbons (PAHs)
• selective ion monitoring (SIM)

Additional information

Funding

This work was generously supported by the Research and Development Center of China Tobacco Sichuan Industrial Corporation, which is hereby gratefully acknowledged.