Ultrasonic nebulization headspace ionic liquid-based single drop microextraction of flavour compounds in fruit juices

The ultrasonic nebulization headspace ionic liquid-based single drop microextraction was developed for the extraction of flavour constituents from fruit juices. The GC-MS was applied to the separation and detection of the constituents. The parameters affecting extraction performance, such as microdrop volume, extraction time, enrichment time, extraction temperature, and position of microdrop, were investigated and optimized. The optimized system was: ionic liquid, 1-hexyl-3-methylimidazolium tetrafluroborate; solvent microdrop volume, 12.5 μL; extraction time, 5 min; enrichment time, 20 min; extraction temperature, 80 °C; the height of the microdrop above the solution surface, 1cm; and, the pH value of sample solution did not affect the species, and solubility of analytes. The recoveries were in the range of 80.4-115.0%, and the relative standard deviations were lower than 9.1%. The present method is a simple and sensitive method for the determination of flavour constituents in fruit juices.