Comparison of fully-automated headspace single drop microextraction and headspace solid phase microextraction techniques for rapid analysis of No. 6 solvent residues in edible oil

Rapid, automated and solvent-free are the developing trends of sample preparation technique. In this study, fully-automated microextraction techniques, including headspace solid-phase microextraction (HS-SPME) and static headspace single drop microextraction (HS-SDME), coupled with GC/MS were investigated and compared for rapid analysis of No. 6 solvent residues in edible oil. With the use of Gerstel MultiPurpose autosampler, sample extraction, injection and analysis procedures can be automatically carried out. Under the optimized extraction conditions, the developed methods presented shorter analysis time, lower limits of detections (LODs) and satisfied precisions (RSDs < 6.8%). The LODs of HS-SPME (0.1 μg·g− 1) and HS-SDME (1 μg·g− 1) are much lower than traditional headspace (HS) method (7 μg·g− 1). Moreover, the LOD of the automated HS-SPME-GC/MS method can be lowered to 0.005 μg·g− 1 under splitless mode, due to the solvent-free and less sample introduction nature, and satisfied results were obtained for the analysis of edible oil sample.