title: Stability of colloidal dispersions in the presence of protein fibrils.
abstract: We studied the stability of monodispersed polystyrene latex dispersions with protein fibrils at different concentrations at pH 2 using microscopy and diffusing wave spectroscopy. At low fibril concentrations, fibrils induced bridging flocculation due to the opposite charges between fibrils and the latex particles. At higher fibril concentration the dispersions were stabilized due to steric and/or electrostatic repulsion. Upon further increasing fibril concentration, we find that the dispersion is destabilized again by depletion interaction. At even higher fibril concentration, the dispersions are stabilized again. These dispersions have a higher stability compared to the dispersions without fibrils. Interestingly, these dispersions contain single particles and small clusters of particles that do not grow beyond a certain size. Although the stabilization mechanism is not clear yet, the results from microscopy and diffusing wave spectroscopy point in the direction of a kinetic barrier that depends on fibril concentration.
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University, P.O. Box 17, 6700 AA, Wageningen, The Netherlands. Paul.Venema@wur.nl.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Peng
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University, P.O. Box 17, 6700 AA, Wageningen, The Netherlands. Paul.Venema@wur.nl.
authors.forename: Ardy
authors.initials: A
authors.lastname: Kroes-Nijboer
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University, P.O. Box 17, 6700 AA, Wageningen, The Netherlands. Paul.Venema@wur.nl.
authors.forename: Paul
authors.initials: P
authors.lastname: Venema
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University, P.O. Box 17, 6700 AA, Wageningen, The Netherlands. Paul.Venema@wur.nl.
authors.forename: Erik
authors.initials: E
authors.lastname: van der Linden
mesh_terms: D003102:Colloids; D004058:Diffusion; D007840:Latex; D008853:Microscopy; D066329:Protein Aggregates; D013696:Temperature; D000067816:Whey Proteins / Q000737:chemistry*
chemical_list: D003102:Colloids; D007840:Latex; D066329:Protein Aggregates; D000067816:Whey Proteins