6533b83afe1ef96bd12a78da
RESEARCH PRODUCT
Interaction of polyelectrolytes with oppositely charged micelles studied by fluorescence and liquid chromatography
Armando CodoñerConcepción AbadRosa García-loperaAgustín CamposFrancisco Torrenssubject
ChromatographyAqueous solutionPolymers and PlasticsChemistryOrganic ChemistryGeneral Physics and AstronomyMicellePolyelectrolytePartition coefficientchemistry.chemical_compoundBromideIonic strengthPartition equilibriumCritical micelle concentrationMaterials Chemistrydescription
It is studied by spectrofluorimetry the association of ionized cationic micelles (cetyltrimethylammonium bromide, CTAB) with oppositely charged polyelectrolyte [sodium poly(styrenesulfonate), PSSNa]. CTAB provokes a change in the fluorescence intensity emitted by PSSNa. The investigated surfactants form micelle-like aggregates before critical micellar concentration (CMC). Two approaches (binding and partition equilibrium) are used to obtain the association constant, KA, number of CTAB molecules in a binding site, N, and apparent partition coefficient, Γ. Analysis of the parameters as a function of polymer concentration and ionic strength μ is performed. The effect of μ shows an enhancement in association as μ decreases. Furthermore as CMC decreases with μ, experiments have to be performed at rather different CMCs. This causes KA and Γ to increase with μ. The adsorption of polyelectrolyte on the micelle is also studied at the greatest μ using high-performance liquid chromatography (size-exclusion) for the first time, obtaining results similar to those found using spectrofluorimetry.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2005-06-01 | European Polymer Journal |