Ionic liquids (ILs) were discovered by Paul Walden in 1914 while studying the properties of ethylamine salt of nitric acid, (m.p. 13–14°C) [1], and since the beginning, they have been the object of in depth studies in several disciplines of chemistry. ILs are organic salts liquid below 100°C and consists of an organic cation (in general N or P based) and an organic or inorganic anion. They are in general characterized by high thermal stability, negligible vapor pressure, unique solvating properties due to polarity and ionic character of molten salts, and, at the same time, of non-flammability, variable viscosities, conductivity, and miscibility in different solvents. ILs have enjoyed a remarkable success also in analytical and bioanalytical chemistry. Their properties are related to the electrostatic interactions of the analytes with the cationic and/or anionic moiety, which make ILs usable for many analytical applications and excellent alternatives to traditional organic solvents in many sample preparation procedures. At the same time, their possibility to be engineered provide them with an uncommon selectivity toward specific groups of compounds. The combination of these properties enables them i) to give high preconcentration rate for several sample preparation and detection applications [2,4], and ii) to provide excellent separation efficiency and peak capacities [2,3,5]. This lecture is a quick overview of the role ILs can play in an analytical procedure illustrated by examples from the authors' daily experience in sample preparation, and in biomolecular and gas chromatographic analyses mostly in the field of natural products and foods. [1] P. Walden, Molecular weights and electrical conductivity of several fused salts. Bull. Acad. Imper. Sci. St. Petersbourg, 8 (1914) 405–422. [2] Tien D. Ho, Cheng Zhang, L. W. Hantao, and J. L. Anderson, Ionic liquids in analytical chemistry: fundamentals, advances, and perspectives, Anal. Chem. 86 (2014) 262−285. [3] A. Berthod, M.J. Ruiz-Ángel, S. Carda-Broch, Recent advances on ionic liquid uses in separation techniques, J. Chromatogr. A 1559 (2018) 2–16. [4] K.D. Clark, M.J. Trujillo-Rodríguez, J.L. Anderson, Advances in the analysis of biological samples using ionic liquids. Anal Bioanal Chem. 410 (2018) 4567–4573. [5] C. Cagliero, C. Bicchi, Ionic liquids as gas chromatographic stationary phases: how can they change food and natural product analyses? Anal. Bioanal. Chem. 412 (2020) 17-25.

Ionic Liquids: An “Old” Class of Chemicals of High Interest in Modern Sample Preparation and Analysis

C. Bicchi;C. Cagliero
2021-01-01

Abstract

Ionic liquids (ILs) were discovered by Paul Walden in 1914 while studying the properties of ethylamine salt of nitric acid, (m.p. 13–14°C) [1], and since the beginning, they have been the object of in depth studies in several disciplines of chemistry. ILs are organic salts liquid below 100°C and consists of an organic cation (in general N or P based) and an organic or inorganic anion. They are in general characterized by high thermal stability, negligible vapor pressure, unique solvating properties due to polarity and ionic character of molten salts, and, at the same time, of non-flammability, variable viscosities, conductivity, and miscibility in different solvents. ILs have enjoyed a remarkable success also in analytical and bioanalytical chemistry. Their properties are related to the electrostatic interactions of the analytes with the cationic and/or anionic moiety, which make ILs usable for many analytical applications and excellent alternatives to traditional organic solvents in many sample preparation procedures. At the same time, their possibility to be engineered provide them with an uncommon selectivity toward specific groups of compounds. The combination of these properties enables them i) to give high preconcentration rate for several sample preparation and detection applications [2,4], and ii) to provide excellent separation efficiency and peak capacities [2,3,5]. This lecture is a quick overview of the role ILs can play in an analytical procedure illustrated by examples from the authors' daily experience in sample preparation, and in biomolecular and gas chromatographic analyses mostly in the field of natural products and foods. [1] P. Walden, Molecular weights and electrical conductivity of several fused salts. Bull. Acad. Imper. Sci. St. Petersbourg, 8 (1914) 405–422. [2] Tien D. Ho, Cheng Zhang, L. W. Hantao, and J. L. Anderson, Ionic liquids in analytical chemistry: fundamentals, advances, and perspectives, Anal. Chem. 86 (2014) 262−285. [3] A. Berthod, M.J. Ruiz-Ángel, S. Carda-Broch, Recent advances on ionic liquid uses in separation techniques, J. Chromatogr. A 1559 (2018) 2–16. [4] K.D. Clark, M.J. Trujillo-Rodríguez, J.L. Anderson, Advances in the analysis of biological samples using ionic liquids. Anal Bioanal Chem. 410 (2018) 4567–4573. [5] C. Cagliero, C. Bicchi, Ionic liquids as gas chromatographic stationary phases: how can they change food and natural product analyses? Anal. Bioanal. Chem. 412 (2020) 17-25.
2021
1st European Sample Preparation e-Conference
online
March 11-12, 2021
1st European Sample Preparation e-Conference - book of abstract
EuChemS
39
39
978-2-9601655-9-3
Biomolecular analysis, Gas chromatography, Ionic liquids, Sample preparation
C. Bicchi, C. Cagliero
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1799302
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