Since their initial discovery in 1914, ionic liquids (ILs) have been widely studied in multiple chemistry disciplines. Applications of ILs in analytical chemistry have enjoyed much success and contributed to the rapid evolution of the ionic liquid field. ILs are collectively known as organic salts which possess melting points at or below 100 °C. In most cases, ILs are composed of an organic cation and an organic or inorganic anion. It has been estimated there can be up to 1018 possible combinations of ILs, due to the ability to interchange their corresponding cationic/anionic moieties.
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