Ionic liquids (ILs) defined as organic salts that produced from combination of organic cation with various types of organic/inorganic anions whose melting point less than 100°C. Because of their ionic character, most of ionic liquids exhibit useful properties such as no volatility, recyclability, good thermal stability, high conductivity and chemical stability. Ionic liquid cation - anion combinations permits the solvents to be prepared such as N, N-dialkylimidazolium as cation and acetate as anion. Ionic liquid was utilized as solvents or preparation components in various areas of drug delivery systems, also as novel liquid forms of APIs in various stages of design drug delivery systems. Also their incorporation with polymers has enabled the development of drug delivery systems for new therapeutic routes of administration. Recently ionic liquid can be used as solubility and permeability enhancer to deliver drugs with poor aqueous solubility and low lipophilicity by designing topical drug delivery of nano system.


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