title: Impact of cationic surfactant on the self-assembly of sodium caseinate.
abstract: The impact of a cationic surfactant, dodecylammonium chloride (DDACl), on the self-assembly of sodium caseinate (SC) has been investigated by light scattering, zeta potential, and rheological measurements as well as by microscopy (transmission electron and confocal laser scanning microscopy). In SC dilute solutions concentration-dependent self-assembly proceeds through the formation of spherical associates and their aggregation into elongated structures composed of connected spheres. DDACl interacts with SC via its hydrophilic and hydrophobic groups, inducing changes in SC self-assembled structures. These changes strongly depend on the surfactant aggregation states (monomeric or micellar) as well as concentration ratio of both components, leading to the formation of soluble and insoluble complexes of nano- to microdimensions. DDACl monomers interact with SC self-assembled entities in a different way compared to their micelles. Surfactant monomers form soluble complexes (similar to surfactant mixed micelles) at lower SC concentration but insoluble gelatinous complexes at higher SC concentration. At surfactant micellar concentration soluble complexes with casein chains wrapped around surfactant micelles are formed. This study suggests that the use of proper cationic surfactant concentration will allow modification and control of structural changes of SC self-assembled entities.
authors: Department of Chemistry, Faculty of Agriculture, and ‡Department of Histology and Embryology, School of Medicine, University of Zagreb , Zagreb, Croatia.
authors: Marko
authors: M
authors: Vinceković
authors: Marija
authors: M
authors: Curlin
authors: Darija
authors: D
authors: Jurašin
mesh_terms: D000588:Amines / Q000737:chemistry*; D002364:Caseins / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008823:Micelles; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D000588:Amines; D002364:Caseins; D008823:Micelles; D013501:Surface-Active Agents; C003935:dodecylamine