Revisiting the internal conformational dynamics and solvation properties of cyclodextrins

Journal of the Brazilian Chemical Society

Cristina S. Pereira¹  André F. De Moura²  Luiz Carlos G. Freitas²  Roberto D. Lins² 

[1] ,Swiss Federal Institute of Technology Zürich Laboratory of Physical Chemistry Zürich,Switzerland

关键词: cyclodextrins;    molecular dynamics;    solvation;    flexibility;   

DOI  :  10.1590/S0103-50532007000500012

来源: SciELO

【 摘 要 】

Molecular dynamics simulations were used to investigate the internal conformational dynamics and solvation properties of the three natural cyclodextrins, a-, b- and gamma-cyclodextrin in aqueous solution at room temperature. These glucose-derived oligosacharides present a molecular structure that confers them the ability to complex guest molecules and change their physicochemical properties. The structural behavior of cyclodextrins in solution is crucial for their complexation abilities. Analyses of the obtained trajectories show that inter-glucose hydrogen bonds between the secondary hydroxyl groups are present in solution, but show a very dynamical character where alternative hydrogen bonds to water molecules can be formed. Despite the lower hydrophilicity of the cyclodextrins inner-cavities, they were found to be solvated and the number of water molecules inside the cavity roughly doubles per glucose unit added to the ring. The residence times for water molecules inside the cavities are inversely proportional to the cavity size.

【 授权许可】

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