Characterization of surface-confined ionic liquid stationary phases: impact of cation and anion identity on retention.
A series of surface-confined ionic liquid (SCIL) stationary phases for high-performance liquid chromatography were synthesized in-house. The synthesized phases were characterized by the linear solvation energy relationship (LSER) method to determine the effect of residual linking ligands and the role of the cation and the anion on retention. Statistical analysis was utilized to determine whether the system coefficients returned from multiple linear regression analysis of chromatographic retention data for a set of 28 neutral aromatic probe solutes were significantly different. Examination of the energetics of retention via kappa-kappa plots agrees with the results obtained from the LSER analysis. Residual linking ligands were determined to contribute reversed-phase-type retention character to the chromatographic system. Furthermore, retention on the SCIL phases was observed to be more profoundly affected by the identity of the anion than by that of the cation.
Van Meter
David S
DS
Department of Chemistry, University of Cincinnati, Cincinnati, OH, 45221, USA.
Oliver
Nyoté J
NJ
Carle
A Björn
AB
Dehm
Sabine
S
Ridgway
Thomas H
TH
Stalcup
Apryll M
AM
D000838:Anions / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D007093:Imidazoles / Q000737:chemistry; D052578:Ionic Liquids / Q000138:chemical synthesis / Q000737:chemistry*; D008024:Ligands; D016014:Linear Models; D015394:Molecular Structure; D012821:Silanes / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors
D000838:Anions; D002412:Cations; D007093:Imidazoles; D052578:Ionic Liquids; D008024:Ligands; D012821:Silanes; D012997:Solvents