– Multivalent ions can induce condensation of like-charged polyelectrolytes into compact states, a process that requires different ion valence for different polyelectrolyte species. We have examined the trivalent ion induced condensation behavior in binary anionic polyelectrolyte mixtures consisting of DNA coils and F-actin rods, and observe a micro-phase separation between the two polyelectrol...

The surface charge of isolated apolipoprotein A-I, apo-A-II, apo-C-II, and apo-C-III2 as well as of liposomes from synthetic highly purified phospholipids and isolated very low density lipoprotein (VLDL) particles from different donors (n = 35) was determined by polyelectrolyte titration. The particle size of apolipoproteins was evaluated from their molecular weight and specific volume, while t...

The coadsorption of a positively charged polyelectrolyte (with 10% of the segments carrying a permanent positive charge, AM-MAPTAC-10) and an anionic surfactant (sodium dodecyl sulfate, SDS) on silica and glass surfaces has been investigated using optical reflectometry and a noninterferometric surface force technique. This is a selective coadsorption system in the sense that the polyelectrolyte...

The interactions between anionic polyelectrolytes [polyacrylic acid, poly(methyl vinyl etherco-maleic anhydrate)] and copper ions in aqueous solution (pH 7.0) were investigated by dynamic light scattering, UV-visible and fourier transform infrared spectroscopic techniques. Viscosity was also measured by ubbelohde automatic viscometer. Observations indicate that the ratio of ingredients, the nat...

The association between low-charge-density polyelectrolytes adsorbed onto negatively charged surfaces (mica and silica) and an anionic surfactant, sodium dodecyl sulfate (SDS), has been investigated using surface force measurements, ellipsometry, and XPS. All three techniques show that the polyelectrolyte desorbs when the SDS concentration is high enough. The XPS study indicates that desorption...

Highly charged hydrophilic superparamagnetic Fe3O4 colloidal nanocrystal clusters with an average diameter of 195 nm have been successfully synthesized using a modified one-step solvothermal method. Anionic polyelectrolyte poly(4-styrenesulfonic acid-co-maleic acid) sodium salt containing both sulfonate and carboxylate groups was used as the stabilizer. The clusters synthesized under different ...

The structural organization and thermomechanical properties of nanocomposites prepared from interpolyelectrolyte-metal complex (IMC) involving anionic polyelectrolyte, pectin and AgNO3, and cationic polyelectrolyte, poly(4-vinylpyridine), have been investigated using the methods of wide- and small-angle X-ray scattering and thermomechanical analysis. It is established that chemical reduction of...

We report that user-defined DNA nanostructures, such as two-dimensional (2D) origamis and nanogrids, undergo a rapid higher-order folding transition, referred to supra-folding, into three-dimensional (3D) compact structures (origamis) or well-defined μm-long ribbons (nanogrids), when they adsorb on soft cationic substrate prepared by layer-by-layer deposition of polyelectrolytes. Once supra-fol...

Pulp fibers have a strong tendency to form flocs in water suspensions, which may cause their undesirable distribution in the paper sheets. This flocculation can be controlled by adding, e.g., an anionic high molecular weight polyelectrolyte in the fiber suspension. The objective of this study was to investigate the effect of anionic polyelectrolytes on deflocculation kinetics, dewatering, and r...