Adsorption of polyelectrolytes on silica and gold surfaces. (2nd August 2016)

• Record Type: Journal Article
• Authors: Balderas Altamirano, M. A.; Camacho, R.; Pérez, E.; Goicochea, A. Gama
• Is Part Of: Molecular physics. Volume 114:Number 15(2016)
• Page Start: 2253
• Page End: 2264
• Publication Date: 2016-08-02
• Subjects: Polyelectrolyte adsorption -- nanoparticles -- dissipative particle dynamics -- polymer bridging; Molecules -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Molécules -- Périodiques; Chimie physique et théorique -- Périodiques; 539.6.05
• DOI: 10.1080/00268976.2016.1194496
• Languages: English
• ISSNs: 0026-8976

Abstract

ABSTRACT: The results of a study that helps understand the mechanisms of adsorption of polyelectrolytes on particles, using numerical simulation methods, specifically the one known as dissipative particle dynamics are reported here. The adsorption of cationic polyelectrolytes of two different polymerisation degrees interacting with two types of surfaces, one made of gold and the other of silica, is predicted and compared. We find that a more negatively charged wall does not necessarily adsorb more cationic polyelectrolytes because the electrostatic repulsion between the wall and the polyelectrolytes is stronger. Additionally, intra-chain repulsion plays an important role, because the largest polyelectrolyte chains have larger excluded volume than the shorter ones. In regard to the adsorption dependence on the polyelectrolyte polymerisation degree, we find that the excluded volume drives the adsorption throughout the intra-chain electrostatic repulsion, because the SiO2 surface is strongly negative. These results are expected to be useful for several nanotechnological applications of current interest, such as in gene therapy and in the improvement of drug delivering mechanisms. Abstract :