Thermal dissociation of protonated cyclodextrin-amino acid complexes in the gas phase

Dissociation temperatures of protonated gas-phase amino acid-cyclodextrin complexes were determined by producing the complexes with electrospray ionization and passing them through a resistively heated capillary. The dissociation temperatures of the complexes increased with the number of hydrogen bonding interactions and the ability of the cyclodextrin host to sterically lock the amino acid guest in place. There was little correlation between the gas-phase basicity of the amino acid and the dissociation temperature. Molecular modeling was used to better understand the nature of the interactions. (C) 2001 Elsevier Science B.V.