Thermal study of water/β-cyclodextrin interactions (original) (raw)

It is shown that water/13-cyclodextrin system has a complex behaviour above room temperature, and displays phenomena which may be separately analyzed under carefully chosen conditions: in dry atmosphere, and/or below 60 ° C, the release of water occurs much faster than the expected structural transformation from the hydrated to the dehydrated structure. It is argued that this transition contributes substantially to the endothermic DSC peak usually attributed to dehydration. After completing its first transition to the dehydrated structure, a water grown sample undergoes a dramatic (~ 15%) and irreversible expansion, which apparently does not modify the crystal structure.