Ionic liquids and cyclodextrin inclusion complexes: limitation of the affinity capillary electrophoresis technique

The state of the art of inclusion complex formation between cyclodextrins and ionic liquids is reported. Mechanisms, stoichiometries, and binding constants are summarized and classified by anion. We investigated the supramolecular interactions between the beta-cyclodextrin cavity and six ionic liquids based on 1-dodecyl-3-methylimidazolium by affinity capillary electrophoresis and compared the results with those obtained by isothermal titration calorimetry. We show that the presence of basic or acidic buffers leads to a metathesis reaction, underlining the limitation of the affinity capillary electrophoresis technique.