پديدآورندگان :
Sadeghi Susan ssadeghi@birjand.ac.ir Department of Chemistry, University of Birjand, Birjand, Iran;
چكيده فارسي :
Ionic liquids (ILs) are mixtures of low melting point organic salts resulting from organic cations, starting with imidazolium cations, and organic or inorganic anions. The cationic component has been varied to other cations such as pyridinium, phosphonium, and thiazolium species. The ionic liquids that have a melting point lower than ambient temperature are defined as room temperature ionic liquids (RTIL) which are labeling as designer solvents. Depending on the structure of the cations and anions, many ILs with different physical properties have been obtained. The designer nature of ILs has driven their exploration and utilization in numerous fields among the physical and chemical sciences such as batteries, dye-sensitized solar cells, fuel cells, electrochemistry, gas separations, polymer chemistry, organic synthesis, biomolecular stabilization and activation, and nanoscience [1]. Deep eutectic solvents (DESs) are a new innovative class of solvents obtained by mixing solid compounds that are not necessarily salts, obtaining a eutectic mixture with a melting point that is much lower than that of the individual components [2].Due to their unique properties, ionic liquids are regarded as good candi¬dates to replace organic solvents in many industrial processes and have attracted attention as green solvents in extraction in recent years. High viscosity and low vapor pressure of ILs, enable them to form large and stable microdroplets that prohibit them to evaporate during extraction. This can provide superior analyte extraction capabilities as well as improved analytical precision compared to organic solvents. In addition, a wide range of new processes based on ionic liquids has been developed for the selective separation of important components, namely organic compounds, metal species, biomolecules and pollutant gases from waste [3]. To use a solvent for extraction processing of an analyte, the solubility and toxicity are other relevant factors for any chemical to be used in medicine, and other related areas. Fortunately, in recent years, nontoxic ILs have been synthesized by selecting biocompatible organic cations and inorganic anions. The ability to tune the selectivity of ILs, enables high preconcentration of analytes in various sample preparation and detection techniques. Various task-specific ionic liquids with certain groups have been constructed and are generally used in techniques such as liquid–liquid extraction and solid-phase extraction [4]. On the other hand, IL-modified materials as selective sorbents can be applied as stationary phases with unique selectivities, thermal stabilities, excellent separation efficiency and high peak capacities in gas chromatography, high-performance liquid chromatography and electrophoresis [5]. Magnetic ionic liquids (MILs) have recently generated innovative applications in numerous areas of analytical chemistry. Functionalizing MILs with long aliphatic groups to impart hydrophobic character enables their use in aqueous extraction systems.In this lecture, recent developments and progress concerning ionic liquids, and their applications in analytical chemistry will be reviewed. It also highlights their emerging use for extraction and separation of analytes. Several examples including some of the current studies in our laboratory will be presented. Potential applications, current challenges and future perspectives will be discussed.
