Revisiting the internal conformational dynamics and solvation properties of cyclodextrins

Journal of the Brazilian Chemical Society

Freitas, Luiz Carlos G.¹  Swiss Federal Institute of Technology Zürich, Zürich, Switzerland¹  Moura, André F. de¹  Pereira, Cristina S.¹  Universidade Federal de São Carlos, São Carlos, Brazil¹  Pacific Northwest National Laboratory, Richland, USA¹  Lins, Roberto D.¹ 

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

DOI  :  10.1590/S0103-50532007000500012

学科分类：化学（综合）

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 g-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】

Unknown