alfa-, beta-, and gamma-cyclodextrins (CDs) marketed by five different companies were characterized from the thermal and structural point of view. Three aCD samples showed two-step DSC dehydration profiles and their XRD patterns were characteristic for alfaCD·6H2O form I, whereas one brand with an apparent three-step DSC dehydration behaviour was a mixture of alfaCD·6H2O form I and anhydrous alfaCD. The differences in the DSC profiles after dehydration and EGA onset decomposition temperatures recorded for the five betaCD brands were attributed to different manufacturing and purification processes. The five gammaCDs brands showed a common thermal behaviour and very similar XRD patterns. The patterns did not match the idealized pattern of gammaCD·14.1H2O, indicating the occurrence of two different hydrated crystal structures.
Thermal and structural characterization of commercial a-, b, and g-cyclodextrins
BETTINETTI, GIAMPIERO;SORRENTI, MILENA LILLINA
2002-01-01
Abstract
alfa-, beta-, and gamma-cyclodextrins (CDs) marketed by five different companies were characterized from the thermal and structural point of view. Three aCD samples showed two-step DSC dehydration profiles and their XRD patterns were characteristic for alfaCD·6H2O form I, whereas one brand with an apparent three-step DSC dehydration behaviour was a mixture of alfaCD·6H2O form I and anhydrous alfaCD. The differences in the DSC profiles after dehydration and EGA onset decomposition temperatures recorded for the five betaCD brands were attributed to different manufacturing and purification processes. The five gammaCDs brands showed a common thermal behaviour and very similar XRD patterns. The patterns did not match the idealized pattern of gammaCD·14.1H2O, indicating the occurrence of two different hydrated crystal structures.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.