RT Journal Article
T1 On the Urea Action Mechanism: A Comparative Study on the Self-Assembly of Two Sugar-Based Surfactants.
A1 Hierrezuelo-Osorio, José Manuel
A1 Molina-Bolivar, Jose Antonio
A1 Carnero-Ruiz, Cristóbal
K1 Fluorescencia
K1 Micelas
K1 Agentes tensioactivos
AB Studies on the effect of urea on micelle formation and structure of n-octyl- -D-thioglucoside (OTG) and N-decanoyl-N-methylglucamide (MEGA-10) were carried out by using the steady-state and time-resolved fluorescence techniques, together with combined static and dynamic light scattering measurements. A similar increase in the critical micelle concentration with the urea addition was observed for both surfactants. This behavior was attributed to a rise in the solubility of hydrocarbon tails and the increase of solvation of the headgroup of the surfactants in the presence of urea. Structural studies mainly based on the analysis of the hydrodynamic radius and aggregation number of micelles revealed that urea induces changes much more significant on micelles of OTG. Particularly, it was found that, whereas the surface area per headgroup of OTG increases with the urea concentration, it does decrease in the case of MEGA-10. This fact suggests that different action mechanisms operate for both surfactants. Accordingly, investigations on the micellar microstructure based on the study of microenvironmental properties such as micropolarity and microviscosity also indicated a more pronounced effect in the case of OTG. Although changes were not observed in the hydrophobic inner region of both micellar systems, a significant increase of polarity and viscosity in the micellar interface of OTG suggests a direct participation of urea in the micellar solvation layer. The differences between the observed behaviors for both micellar systems were interpreted on the basis of two features: the weaker hydration and greater rigidity of the OTG headgroup as compared with MEGA-10.
PB ACS
YR 2009
FD 2009-04-24
LK https://hdl.handle.net/10630/33298
UL https://hdl.handle.net/10630/33298
LA eng
NO J. Phys. Chem. B 2009, 113, 20, 7178–7187
NO https://v2.sherpa.ac.uk/id/publication/21299?template=romeo
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 4 mar 2026