Characterization of the Cyclodextrin−Surfactant Interactions by Volume and Enthalpy
- 1 November 2003
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry B
- Vol. 107 (47), 13150-13157
- https://doi.org/10.1021/jp034105a
Abstract
Volume and enthalpy of transfer of hydroxypropyl-α-cyclodextrin (HP-α-CD) and hydroxypropyl-γ-cyclodextrin (HP-γ-CD) from water to the aqueous solutions of sodium alkanoates (sodium hexanoate, sodium decanoate and sodium dodecanoate) were determined at 298 K. The cyclodextrin concentration was kept constant, and that of the surfactant was varied in order to analyze both the pre- and postmicellar regions. The experimental data in the premicellar region were consistent with the formation of 1:1 and 1:2 (1 cyclodextrin:2 surfactants) inclusion complexes, with the exception of the HP-α-CD/sodium dodecanoate system which presented only the 1:1 complexes. The mechanism of the 1:2 complexes formation of HP-α-CD/surfactant is different from that involving HP-γ-CD. The quantitative analysis of the experimental data in the post-micellar region supplied parameters indicating that the cyclodextrin−micelles forces are ion−dipole (carboxylate head/hydroxylic group) in nature. The present results combined with the literature ones clarify the effect of the cavity size of the cyclodextrin as well as the hydrophobicity of the surfactant on the cyclodextrin-dispersed surfactant and cyclodextrin−micelle interactions.Keywords
This publication has 37 references indexed in Scilit:
- Binding between (Ethylene Oxide)13−(Propylene Oxide)30−(Ethylene Oxide)13 and Sodium Decanoate. Volume, Enthalpy, and Heat Capacity StudiesThe Journal of Physical Chemistry B, 2002
- Thermodynamic Evidence of Cyclodextrin−Micelle InteractionsThe Journal of Physical Chemistry B, 2002
- Cyclodextrins for Desorption and Solubilization of 2,4,6-Trinitrotoluene and Its Metabolites from SoilEnvironmental Science & Technology, 2000
- Surface Tensiometric Study of Multiple Complexation and Hemolysis by Mixed Surfactants and CyclodextrinsLangmuir, 1999
- Demixing of Mixed Micelles. Thermodynamics of Sodium Perfluorooctanoate−Sodium Dodecanoate Mixtures in WaterLangmuir, 1997
- A Conductimetric Study of the Interaction of .beta.-Cyclodextrin or Hydroxypropyl-.beta.-cyclodextrin with Dodecyltrimethylammonium Bromide in Water SolutionLangmuir, 1995
- Apparent Molar Volumes of Some Hydrogenated and Fluorinated Alcohols in Sodium Dodecanoate and Sodium Perfluorooctanoate Aqueous SolutionsLangmuir, 1995
- Thermodynamic properties of alkyldimethylamine oxides in water. Application of a mass-action model for micellizationThe Journal of Physical Chemistry, 1983
- A Fundamental Equation of State for Heavy WaterJournal of Physical and Chemical Reference Data, 1982
- Topography of cyclodextrin inclusion complexes. 8. Crystal and molecular structure of the .alpha.-cyclodextrin-methanol-pentahydrate complex. Disorder in a hydrophobic cageJournal of the American Chemical Society, 1976