Ultrasonic nebulization extraction coupled with headspace single drop microextraction and gas chromatography-mass spectrometry for analysis of the essential oil in Cuminum cyminum L.

A novel method for analysis of essential oil in Cuminum cyminum L. using simultaneous ultrasonic nebulization extraction and headspace single drop microextraction (UNE-HS-SDME) followed by gas chromatography-mass spectrometry was developed. Experimental parameters, including the kind of suspended solvent, microdrop volume, sample amount, extraction time, enrichment time and salt concentration were examined and optimized. Compared with hydrodistillation (HD), UNE-HS-SDME provides the advantages of a small amount of sample (50 mg), time-saving (20 min), simplicity, cheapness and low toxicity. In addition, UNE-HS-SDME also provided higher enrichment efficiency and sensitivity compared with stirring extraction (SE)-HS-SDME, ultrasonic assistant extraction (UAE) and UNE. Some constituents in the essential oil, were identified and the detection limits for β-pinene, p-cymene and γ-terpinene range from 6.67 pL L⁻¹ to 14.8 pL L⁻¹. The results indicated that the UNE-HS-SDME is simple and highly efficient extraction and enrichment technique.