Nanoparticle halos: a new colloid stabilization mechanism.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 11447264.
- Also identified by PMC identifier 55354.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
A new mechanism for regulating the stability of colloidal particles has been discovered. Negligibly charged colloidal microspheres, which flocculate when suspended alone in aqueous solution, undergo a remarkable stabilizing transition upon the addition of a critical volume fraction of highly charged nanoparticle species. Zeta potential analysis revealed that these microspheres exhibited an effective charge buildup in the presence of such species. Scanning angle reflectometry measurements indicated, however, that these nanoparticle species did not adsorb on the microspheres under the experimental conditions of interest. It is therefore proposed that highly charged nanoparticles segregate to regions near negligibly charged microspheres because of their repulsive Coulombic interactions in solution. This type of nanoparticle haloing provides a previously unreported method for tailoring the behavior of complex fluids.