Artículo de revista
Inclusion Complexes of Cyclodextrins with Galangin: a Thermodynamic and Reactivity Study
Fecha
2010-10Registro en:
JOURNAL OF SOLUTION CHEMISTRY Volume: 39 Issue: 8 Pages: 1168-1177 Published: OCT 2010
0095-9782
DOI: 10.1007/s10953-010-9574-1
Autor
Jullian Matthaei, Carolina
Alfaro, Muriel
Zapata Torres, Gerald Amilcar
Olea Azar, Claudio
Institución
Resumen
The formation of the complexes of galangin (GAL) with native β-cyclodextrin
(βCD), and with its substituted counterparts such as dimethyl-βCD (DMβCD) and
hydroxypropyl-βCD (HPβCD), was studied by fluorescence spectra in aqueous medium.
The binding association constants (Ka) of the complexes were determined at different temperatures.
The formation constants obtained have the following trend upon complex formation
at the three temperatures studied: HPβCD > DMβCD > βCD. The thermodynamic
data for the inclusion of GAL in DMβCD and HPβCD indicated that is mainly enthalpy
driven whereas for βCD it is an entropy-driven process.
The antioxidant ability studies of GAL and CD complexes showed practically no change
in its activity when the β-cyclodextrin complex is formed. The decrease in the Teq observed
for GAL-DMβCD and GAL-HPβCD in comparison with GAL-βCD could be due to effective
protection of the phenol group in the cyclodextrin cavity, which is in agreement with
molecular modeling studies.