Study of the Interactions of Ionic Liquids in IC by QSRR

• Published in: Chromatographia Vol. 73; no. Suppl 1; pp. 35 - 44
• Main Authors: Studzińska, S., Molíková, M., Kosobucki, P., Jandera, P., Buszewski, B.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.06.2011; Springer
• Subjects: Analytical Chemistry; Chemistry; Chemistry and Materials Science; Chromatographic methods and physical methods associated with chromatography; Chromatography; Exact sciences and technology; Laboratory Medicine; Original; Other chromatographic methods; Pharmacy; Proteomics; Ion-exchange; Ion chromatography; Ionic liquid cations; Hydrophobicity; Quantitative structure–retention relationships (QSRR); Molecular interactions; Chromatographic retention; Prediction; Molecular interaction; Modeling; Ionic liquid; Molecular model; Property structure relationship; Chemometrics; Cation exchanger; Lipophilicity; Physicochemical properties; Quantitative structure-retention relationships (QSRR) Ionic liquid cations
• ISSN: 0009-5893; 1612-1112
• DOI: 10.1007/s10337-011-1960-3

The nature of ionic liquids (ILs) facilitates their analysis by ion chromatography which, unlike conventional high-performance liquid chromatography, enables analysis both of cations and anions. This paper describes a pioneering ion-chromatographic investigation of IL cations and statistical evaluation of quantitative structure–retention relationships with the objective of predicting the molecular mechanism responsible for retention. Eleven ionic liquid imidazolium and pyridinium cations were analyzed on a CS15 cation-exchange column by isocratic elution with acetonitrile–methanesulfonic acid mixtures. Structural descriptors of the cations obtained from molecular modeling were used to describe their hydrophobicity as determined by chromatography. The most statistically significant were three-term QSRR regression equations relating log k w to analyte n -octanol–water partition coefficient (log P ), dipole moment ( μ ), solvent accessible surface area ( A SAS ), and hydration energy (HE). They indicate the important role of both hydrophobic and polar the retention of ILs on the CS15 column.