TY - JOUR
T1 - Zwitterion formation in gas-phase cyclodextrin complexes
AU - Ahn, Seonghee
AU - Cong, Xin
AU - Lebrilla, Carlito B
AU - Gronert, Scott
PY - 2005/2
Y1 - 2005/2
N2 - Protonated complexes of amino acids and underivatized β-cyclodextrin, produced by electrospray ionization and trapped in the Fourier transform mass spectrometer, undergo formation of ternary complexes when reacted with alkyl amine. Based on the reactivities of the protonated amino acid complexes with alkylamines, the reactivities of the corresponding amino acid esters, and partially derivatized β-cyclodextrin hosts, we conclude that the ternary complexes are salt-bridge zwitterionic species composed of amino acid zwitterions and protonated alkylamine all interacting with the hydroxyl groups on the narrow rim of the cyclodextrin. Molecular modeling calculations and experimental results suggest that the interactions of the amino acids with the rims contribute greatly to the formation of the zwitterionic species.
AB - Protonated complexes of amino acids and underivatized β-cyclodextrin, produced by electrospray ionization and trapped in the Fourier transform mass spectrometer, undergo formation of ternary complexes when reacted with alkyl amine. Based on the reactivities of the protonated amino acid complexes with alkylamines, the reactivities of the corresponding amino acid esters, and partially derivatized β-cyclodextrin hosts, we conclude that the ternary complexes are salt-bridge zwitterionic species composed of amino acid zwitterions and protonated alkylamine all interacting with the hydroxyl groups on the narrow rim of the cyclodextrin. Molecular modeling calculations and experimental results suggest that the interactions of the amino acids with the rims contribute greatly to the formation of the zwitterionic species.
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U2 - 10.1016/j.jasms.2004.10.007
DO - 10.1016/j.jasms.2004.10.007
M3 - Article
C2 - 15694767
AN - SCOPUS:13444266185
VL - 16
SP - 166
EP - 175
JO - Journal of the American Society for Mass Spectrometry
JF - Journal of the American Society for Mass Spectrometry
SN - 1044-0305
IS - 2
ER -