Structural behaviour of 2-hydroxypropyl-beta-cyclodextrin in water: molecular dynamics simulation studies.
OBJECTIVE
To investigate the effect of 2-hydroxypropyl side group substitutions on the structure of beta-cyclodextrin (CD) in water.


METHODS
Molecular dynamics simulations were carried out on four HPBCDs that broadly represent a range of degree of substitutions in order to investigate the effect of substitution of beta-cyclodextrin with 2-hydroxypropyl groups at various O2 and O6 positions of the glucose units.


RESULTS
The 2-hydroxypropyl side groups located at the O2 positions widen the cavity entrance at the secondary OH position of the CD molecule. These groups are spatially more spread out but dynamically more restricted, due to the formation of a hydrogen bond network between the hydroxyl groups of the side chains and the glucose units. On the other hand, the 2-hydroxypropyl groups at the O6 positions are dynamically more flexible.


CONCLUSIONS
The extent and the location of the substitution can affect the cavity structure of the CD molecule, and thus possibly the molecular encapsulation capabilities.
Yong
Chin Weng
CW
Computational Science and Engineering Department, Daresbury Laboratory, STFC, Daresbury, Warrington, UK. c.w.yong@dl.ac.uk
Washington
Clive
C
Smith
William
W
D000073738:2-Hydroxypropyl-beta-cyclodextrin; D000465:Algorithms; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D005947:Glucose / Q000737:chemistry; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D014867:Water / Q000737:chemistry; D047392:beta-Cyclodextrins / Q000737:chemistry*
D047392:beta-Cyclodextrins; D014867:Water; D000073738:2-Hydroxypropyl-beta-cyclodextrin; D005947:Glucose