Hydrophobic deep eutectic solvents as pseudo-stationary phases in capillary electrokinetic chromatography: An explorative study.

Research into the application of deep eutectic solvents (DESs) in capillary electrophoresis (CE) is still in its infancy. Even so, a controversy has already arisen over the "true role" of DESs in CE. This is because the DESs employed previously were all hydrophilic, and it is therefore reasonable to speculate that they may be virtually completely dissociated into its initial components (hydrogen-bond acceptor (HBA) and hydrogen-bond donor (HBD)) in aqueous CE buffers.

Use of Gamithromycin as a Chiral Selector in Capillary Electrophoresis.

In this short communication, we report the use of a second-generation macrolide antibiotic, gamithromycin (Gam), as a novel chiral selector for enantioseparation in capillary electrophoresis (CE). A preliminary analysis of the experiment results shows that Gam is especially suitable for the separation of chiral primary amines. Factors influencing enantioseparations were systematically investigated including the composition of the background electrolyte (BGE), concentration of Gam, the type and proportion of organic solvents, applied voltage, etc.

Evaluation of tetraalkylammonium amino acid ionic liquids as chiral ligands in ligand-exchange capillary electrophoresis.

The application of chiral ionic liquids (ILs) in capillary electrophoresis (CE) for enantioseparation has received considerable attention in the past few years; however, the use of chiral ILs as ligands in ligand-exchange capillary electrophoresis (LE-CE) has been reported only in a few papers. In this work, several tetraalkylammonium amino acid ILs (TAA-AAILs) including tetramethylammonium-l-arginine (TMA-l-Arg), tetramethylammonium-l-proline (TMA-l-Pro) and tetramethylammonium-l-glutamic acid (TMA-l-Glu) were first applied in LE-CE to act as chiral ligands for enantioseparation. The results show that TMA-l-Arg-is an excellent chiral ligand, and able to yield equal or even better resolutions (Rs) in much shorter migration times for most tested analytes compared with previously reported AAILs ligands or free l-Arg-ligand.

Investigation of the synergistic effect of chiral ionic liquids as additives in non-aqueous capillary electrophoresis for enantioseparation.

In this work, tetraalkylammonium amino acid ionic liquids (TAA-AAILs) were first applied to non-aqueous capillary electrophoresis (NACE) to establish synergistic systems with a conventional chiral selector, native β-cyclodextrin (β-CD). Excellent enantioseparations of some dansyl-amino acid (Dns-AA) samples were achieved. A series of comparison experiments and a molecular docking study were performed to validate the synergistic effect of TAA-AAILs and β-CD in NACE.