Study on preparation and inclusion behavior of inclusion complexes between beta-cyclodextrin derivatives with benzophenone

摘要

In the paper, the two chemically modified beta-cyclodextrin derivatives of 4,4A '-diaminodiphenyl ether-bridged-bis-beta-cyclodextrins (ODA-bis-beta-CD) and p-aminobenzenesulfonic acid-beta-cyclodextrin (ABS-beta-CD) were synthesized, and then these two beta-cyclodextrin derivatives were respectively formed into inclusion complexes with benzophenone (BP) by co-precipitation method. The structure of the inclusion complexes were characterized by UV/vis spectroscopy, FT-IR spectroscopy, elemental analysis, H-1 NMR spectroscopy and XRD. Spectral titration was performed to study the inclusion behavior of the inclusion complexes. These experiments indicated that two inclusion complexes were formed at a stoichiometric ratio of 1:1 and the inclusion stability constants at different temperatures were calculated using the Benesi-Hildebrand (B-H) equation. The thermodynamic parameters (Delta GA degrees, Delta HA degrees, Delta SA degrees) were obtained. As a result, it was found that the two chemically modified beta-cyclodextrins containing BP were exothermic and spontaneous process (Delta GA degrees 0), and the processes of inclusion complexation were mainly enthalpy driven with negative or minor negative entropic contribution.