Microwave-assisted silylation followed by gas chromatography/mass spectrometry for rapid determination of ergosterol in cigarettes

Ergosterol is one of the important precursors of tumorigenic polynuclear aromatic hydrocarbons. To the best of our knowledge, a large amount of ergosterol is present in moldy cigarettes, which derives from fungal contaminations. Thus, the development of a simple, fast, and efficient method for the analysis of ergosterol is in great demand. In this paper, GC/MS following microwave-assisted silylation (MAS) was developed for the rapid quantitative analysis of ergosterol in cigarettes for the first time. In our work, total ergosterol in cigarettes after NaOH saponification was extracted with hexane, and then was fast derivatized with bis(trimethylsilyl)trifluoroacetamide (BSTFA) under microwave irradiation. Finally, the ergosterol trimethylsilyl derivative was analyzed by GC/MS. Derivatization conditions including microwave reaction solvent, irradiation time, and power were investigated. Method validations (linear range, LOD, precision, and recovery) were also studied. The results showed that the proposed method provided a fast, simple, and sensitive approach for the determination of ergosterol in cigarettes. Finally it was successfully applied to the analysis of ergosterol in normal and mildewy cigarettes.