Ionic Liquids Applied to Extraction of Xenobiotics from Food, Environmental, and Biological Samples and for Analysis by Liquid Chromatography

Ionic liquids (ILs) are a class of unique substances composed purely by cation and anions. Because of the unique properties of ILs (e.g., electric conductivity, low volatility, thermostability, and tenability), their use has attracted considerable interest, including an increasing number of publications on their use in analytical separation techniques. ILs applied as extraction solvents in liquid–liquid extraction methods and promote interactions between the analyte and solvent because of their unique chemical functional groups. In solid-phase extraction, ILs are usually used for the modification of stationary phases. ILs in LC are applied as mobile phase additives to obtain a better peak shape and high system efficiency for the analysis of ionic, especially basic, compounds. This review highlights some of the applications of ILs to extraction and analysis by LC of xenobiotics in food, environmental, and biological samples.