title: Complex formation between ovalbumin and strong polyanion PSSNa: study of structure and properties.
abstract: The mixture system of long-chain polyelectrolyte complexed with a globular protein was investigated based on dynamic light scattering and turbidimetric measurements. We have discussed at different pH values the influence of high salt concentration and mass ratio (protein:PSSNa) on the behavior of the mixture. In dilute concentration regime, the PSSNa chain contracts at pHc by patch binding. We found two critical values of mass ratio: The first corresponds to the maximum shrinking of PSSNa. The second indicates the system that became more stable where the number of proteins attached to the PSSNa chain was constant. The screen of electrostatic interaction shows a high contribution of hydrophobic interaction at large salt concentration to form the coacervates. By building phase diagram, the continuity of pHφ1 in over whole range of salt concentrations and the widening of pH window (pHφ1-pHφ2) were observed. At certain salt concentrations, we can obtain the coexistence of two types of complex particles formed by electrostatic and hydrophobic interactions.
authors: Laboratoire de Physique de la Matière Molle et Modélisation Electromagnétique, Faculté des Sciences de Tunis, Campus Universitaire, 1060, Université El-Manar, Tunisia.
authors: Saber
authors: S
authors: Trabelsi
authors: Laboratoire de Physique de la Matière Molle et Modélisation Electromagnétique, Faculté des Sciences de Tunis, Campus Universitaire, 1060, Université El-Manar, Tunisia. Electronic address: aschi13@yahoo.fr.
authors: Adel
authors: A
authors: Aschi
authors: Laboratoire de Physique de la Matière Molle et Modélisation Electromagnétique, Faculté des Sciences de Tunis, Campus Universitaire, 1060, Université El-Manar, Tunisia.
authors: Tahar
authors: T
authors: Othman
authors: Laboratoire de Physique de la Matière Molle et Modélisation Electromagnétique, Faculté des Sciences de Tunis, Campus Universitaire, 1060, Université El-Manar, Tunisia.
authors: Abdelhafidh
authors: A
authors: Gharbi
mesh_terms: D006863:Hydrogen-Ion Concentration; D008027:Light; D008958:Models, Molecular; D009391:Nephelometry and Turbidimetry; D010047:Ovalbumin / Q000737:chemistry* / Q000378:metabolism*; D000071228:Polyelectrolytes; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism*; D012542:Scattering, Radiation; D012965:Sodium Chloride / Q000737:chemistry; D055672:Static Electricity; D013451:Sulfonic Acids / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D010047:Ovalbumin; D000071228:Polyelectrolytes; D011108:Polymers; D012965:Sodium Chloride; D013451:Sulfonic Acids; C077114:styrenesulfonic acid polymer
keywords: Complex phase; Critical ratio; Dynamic light scattering; Electrostatic interaction; Turbidity