Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins

â-Cyclodextrins ( â - CDs), macrocyclic oligosaccharides formed by seven glucopyranose units, have a rigid lipophilic cavity and can form host - guest inclusion complexes with suitably sized hydrophobic molecules. Water content infl uences the structure of â - CDs and affects the chemical and physic...

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Detalles Bibliográficos
Autores principales: Ponce Cevallos, Peggy Alejandra, Buera, María del Pilar, Elizalde, Beatriz Emilia
Publicado: 2010
Materias:
β-Cyclodextrins - rigid lipophilic cavity
cyclodextrins (CDs) - cyclic oligosaccharides consisting of glucose units
DSC thermograms of complexes - disappearance of fusion peaks of thymol and cinnamaldehyde
Inclusion complexes of thymol and cinnamaldehyde - coprecipitation method
Sorption isotherms - standard isopiestic static-gravimetric method
Water sorption - affecting stability
Water-sorption properties - stability of inclusion complexes
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_97808138_v_n_p149_Ponce
http://hdl.handle.net/20.500.12110/paper_97808138_v_n_p149_Ponce
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_97808138_v_n_p149_Ponce
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spelling paper:paper_97808138_v_n_p149_Ponce2023-06-08T16:37:09Z Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins Ponce Cevallos, Peggy Alejandra Buera, María del Pilar Elizalde, Beatriz Emilia β-Cyclodextrins - rigid lipophilic cavity cyclodextrins (CDs) - cyclic oligosaccharides consisting of glucose units DSC thermograms of complexes - disappearance of fusion peaks of thymol and cinnamaldehyde Inclusion complexes of thymol and cinnamaldehyde - coprecipitation method Sorption isotherms - standard isopiestic static-gravimetric method Water sorption - affecting stability Water-sorption properties - stability of inclusion complexes â-Cyclodextrins ( â - CDs), macrocyclic oligosaccharides formed by seven glucopyranose units, have a rigid lipophilic cavity and can form host - guest inclusion complexes with suitably sized hydrophobic molecules. Water content infl uences the structure of â - CDs and affects the chemical and physical stability of complexed compounds. This work investigated the relationship between the sorption characteristics of â - CDs and complexes formed with thymol and cinnamaldehyde and their release. The complexes were obtained by coprecipitation, fi ltered, freeze - dried, and stored at constant relative humidity (RH) in evacuated chambers (22% - 97%) at 25 ° C. The release of encapsulated compounds was determined after equilibration by differential scanning calorimetry (DSC) following the enthalpy of the fusion peak at 50 ° C (thymol) and 7.5 ° C (cinnamaldehyde). DSC thermograms of complexes after freeze drying showed the disappearance of fusion peaks of thymol and cinnamaldehyde, indicating complex formation. Water - sorption isotherms for â - CD and the complexes showed constant and low water sorption at an RH of less than 80%, and then the uptake of water increased abruptly. At 95% RH, the water adsorbed was in the order â - CD (12.5 mol water/mol â - CD) â - CD - thymol (8.5 mol water/mol complex) â - CD - cinnamaldehyde (7 mol water/mol complex). The guest molecules displaced water molecules from inside the cavity of â - CD. At an RH of less than 84%, thymol and cinnamaldehyde were not released. The percent of released compound abruptly increased from 84% RH, coinciding with the abrupt increase of water. Water sorption signifi cantly affected thymol and cinnamaldehyde complexes with â - CD, and complex stability was thus governed by the shape of the water -sorption isotherm. © 2010 Blackwell Publishing. Fil:Ponce, P.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Buera, M.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Elizalde, B.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2010 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_97808138_v_n_p149_Ponce http://hdl.handle.net/20.500.12110/paper_97808138_v_n_p149_Ponce
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic β-Cyclodextrins - rigid lipophilic cavity
cyclodextrins (CDs) - cyclic oligosaccharides consisting of glucose units
DSC thermograms of complexes - disappearance of fusion peaks of thymol and cinnamaldehyde
Inclusion complexes of thymol and cinnamaldehyde - coprecipitation method
Sorption isotherms - standard isopiestic static-gravimetric method
Water sorption - affecting stability
Water-sorption properties - stability of inclusion complexes
spellingShingle β-Cyclodextrins - rigid lipophilic cavity
cyclodextrins (CDs) - cyclic oligosaccharides consisting of glucose units
DSC thermograms of complexes - disappearance of fusion peaks of thymol and cinnamaldehyde
Inclusion complexes of thymol and cinnamaldehyde - coprecipitation method
Sorption isotherms - standard isopiestic static-gravimetric method
Water sorption - affecting stability
Water-sorption properties - stability of inclusion complexes
Ponce Cevallos, Peggy Alejandra
Buera, María del Pilar
Elizalde, Beatriz Emilia
Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins
topic_facet β-Cyclodextrins - rigid lipophilic cavity
cyclodextrins (CDs) - cyclic oligosaccharides consisting of glucose units
DSC thermograms of complexes - disappearance of fusion peaks of thymol and cinnamaldehyde
Inclusion complexes of thymol and cinnamaldehyde - coprecipitation method
Sorption isotherms - standard isopiestic static-gravimetric method
Water sorption - affecting stability
Water-sorption properties - stability of inclusion complexes
description â-Cyclodextrins ( â - CDs), macrocyclic oligosaccharides formed by seven glucopyranose units, have a rigid lipophilic cavity and can form host - guest inclusion complexes with suitably sized hydrophobic molecules. Water content infl uences the structure of â - CDs and affects the chemical and physical stability of complexed compounds. This work investigated the relationship between the sorption characteristics of â - CDs and complexes formed with thymol and cinnamaldehyde and their release. The complexes were obtained by coprecipitation, fi ltered, freeze - dried, and stored at constant relative humidity (RH) in evacuated chambers (22% - 97%) at 25 ° C. The release of encapsulated compounds was determined after equilibration by differential scanning calorimetry (DSC) following the enthalpy of the fusion peak at 50 ° C (thymol) and 7.5 ° C (cinnamaldehyde). DSC thermograms of complexes after freeze drying showed the disappearance of fusion peaks of thymol and cinnamaldehyde, indicating complex formation. Water - sorption isotherms for â - CD and the complexes showed constant and low water sorption at an RH of less than 80%, and then the uptake of water increased abruptly. At 95% RH, the water adsorbed was in the order â - CD (12.5 mol water/mol â - CD) â - CD - thymol (8.5 mol water/mol complex) â - CD - cinnamaldehyde (7 mol water/mol complex). The guest molecules displaced water molecules from inside the cavity of â - CD. At an RH of less than 84%, thymol and cinnamaldehyde were not released. The percent of released compound abruptly increased from 84% RH, coinciding with the abrupt increase of water. Water sorption signifi cantly affected thymol and cinnamaldehyde complexes with â - CD, and complex stability was thus governed by the shape of the water -sorption isotherm. © 2010 Blackwell Publishing.
author Ponce Cevallos, Peggy Alejandra
Buera, María del Pilar
Elizalde, Beatriz Emilia
author_facet Ponce Cevallos, Peggy Alejandra
Buera, María del Pilar
Elizalde, Beatriz Emilia
author_sort Ponce Cevallos, Peggy Alejandra
title Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins
title_short Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins
title_full Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins
title_fullStr Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins
title_full_unstemmed Water-Sorption Properties and Stability of Inclusion Complexes of Thymol and Cinnamaldehyde with β-Cyclodextrins
title_sort water-sorption properties and stability of inclusion complexes of thymol and cinnamaldehyde with β-cyclodextrins
publishDate 2010
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_97808138_v_n_p149_Ponce
http://hdl.handle.net/20.500.12110/paper_97808138_v_n_p149_Ponce
work_keys_str_mv AT poncecevallospeggyalejandra watersorptionpropertiesandstabilityofinclusioncomplexesofthymolandcinnamaldehydewithbcyclodextrins
AT bueramariadelpilar watersorptionpropertiesandstabilityofinclusioncomplexesofthymolandcinnamaldehydewithbcyclodextrins
AT elizaldebeatrizemilia watersorptionpropertiesandstabilityofinclusioncomplexesofthymolandcinnamaldehydewithbcyclodextrins
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