Supramolecular host-guest interactions of pseudoginsenoside F11 with β- and γ-cyclodextrin: Spectroscopic/spectrometric and computational studies

Pseudoginsenoside F11 (PF11) was described considering its complexation capabilities with beta- and gamma-cyclodextrin. A merged computational/experimental approach was used, and it was found that the PF11 molecule form a stable inclusion complex with the gamma-cyclodextrin, with an association constant of 1.66 x 10(4) M-1, while it is not able to form an analogously one with the ,beta-cyclodextrin. Nuclear magnetic resonance spectroscopy (H-1 NMR, 2D ROESY, and DOSY) and mass spectrometry experiments were used for the study and characterization of the supramolecular complex revealing the effective inclusion of the PF11 in the gamma-cyclodextrin cavity. The thermodynamic parameters and the geometry of the PF11/ cyclodextrin inclusion complex were studied by molecular dynamics simulations and semi-empirical calculations. The results of this study might lead the way for new PF11/gamma-cyclodextrin formulations with advanced bioavailability and targeting. (C) 2019 Elsevier B.V. All rights reserved.