학술논문
Structural transition induced by physicochemical parameters during complexation and coacervation of Poly-L-Ornithine with poly-(sodium 4-styrene sulfonate).
Document Type
Article
Source
Subject
*COACERVATION
*LIGHT scattering
*FRACTAL dimensions
*ELECTROSTATIC interaction
*IONIC strength
*
*
*
*
Language
ISSN
0091-4037
Abstract
We present investigations of the structures and properties of the complex formed by a strong polyanion: poly-(sodium 4-styrene sulfonate) (PSSNa) and weak polycation: poly-L-ornithine (PLO) by combining dynamic light scattering (DLS), ultra-small-angle light scattering (USALS), turbidimetry, and zetametry techniques. The mixtures of polyelectrolytes were controlled in several ways: by the change of pH, modifying the mass ratio, the temperature, and adding divalent salt. Under these conditions, the hydrodynamic radius RH, the viscosity η, the radius of gyration Rg, and the fractal dimension Df were determined. The maximum charge difference of biopolymers stock dispersion was displayed at pH 3.3 and at mass ratio equal to 1. The screen of electrostatic interaction shows a high contribution of hydrophobic interaction at large salt concentration to form the coacervates and the effect of temperature and ionic strength highlighted the strongly hydrophobic character of mixture. The results allowed us to conclude that the complexation was controlled by electrostatic interactions between opposites charges. [ABSTRACT FROM AUTHOR]