Application of Ionic Liquid In-situ Effervescent Extraction in the Analysis of Pesticide Residues of Salvia Miltiorrhiza and Panax Quinquefolium
In this study,a novel in-situ effervescent extraction technology based on acidic ionic liquids was established.The acidic ionic liquid 1-butyl-3-methylimidazole bisulfate is acidic and can react with bicarbonate to produce carbon dioxide,which plays the role of effervescent extraction.It can also be replaced by ion exchange with ammonium hexafluorophosphate to form hydrophobic ionic liquid 1-butyl-3-methylimidazole hexafluorophosphate,which can be separated from water phase by centrifugation to obtain the extraction phase.Finally,the pesticide content in the extraction phase was determined by high performance liquid chromatography.The effects of the dosage of acidic ionic liquid,sodium bicarbonate and sodium chloride on the extraction efficiency were investigated.The optimal extraction conditions were as follows:200 mg acid ionic liquid,0.4 g sodium bicarbonate and 1.0 g sodium chloride.Under the optimal conditions,the linear range of was 0.3~4.0 μg/mL,and the relative deviation(RSD)of intra-day and inter-day was 4.6%and 10.2%,respectively.The recoveries were 94.7%(Panax quinquefolium)and 74.6%(Salvia miltiorrhiza)at the spiked level of 4.0 μg/mL.The method could be used for the treatment of pesticide residues in different substrates of Chinese medicinal materials and decoction pieces.