Influence of Ethanol as a Co-Solvent in Cyclodextrin Inclusion Complexation: A Molecular Dynamics Study.

ABSTRACT: Molecular dynamics (MD) simulations were used to investigate the dynamics and host-guest interactions of the inclusion complexes between a potent anti-HIV agent, UC781, and three different types of cyclodextrins (CDs) including ?CD, 2,6-dimethyl-?CD (M?CD), and 2-hydroxypropyl-?CD (HP?CD) in aqueous solution with ethanol (EtOH) as a co-solvent. The MD simulation results revealed that EtOH as the co-solvent and the type of cyclodextrin affected the inclusion complex formation. From this study, UC781/M?CD provided the most stable inclusion complex. The competition for the cavity of ?CD between UC781 and EtOH and the ensuing occupation of ?CD cavities by EtOH resulted in a weaker interaction between ?CD and UC781. In HP?CD, a supramolecular complex of UC781-HP?CD-EtOH was formed. The EtOH could easily fill the residual void space of the interior of unoccupied HP?CD due to the movement of UC781. In M?CD, the strong hydrogen bond interactions between the UC781 amide group and the secondary hydroxyl groups of M?CD significantly stabilized the inclusion complex in the presence of EtOH.

SUBMITTER: Boonyarattanakalin K 

PROVIDER: S-EPMC4727776 | biostudies-literature | 2015 Apr-Jun

REPOSITORIES: biostudies-literature