Experimental Demonstration of the Stabilization of Colloids by Addition   of Salt
  We demonstrate a general non--Derjaguin-Landau-Verwey-Overbeek method to stabilize colloids in liquids. By this method, colloidal particles that initially form unstable suspension and sediment from the liquid are stabilized by the addition of salt to the suspending liquid. Yet, the salt is not expected to adsorb or directly interact with the surface of the colloids. For the method to work, the liquid should be a mixture, and the salt needs to be antagonistic such that each ion is preferentially solvated by a different component of the mixture. The stabilization may depend on the salt content, mixture composition, or distance from the mixture's coexistence line. 
Sela Samin, Manuela Hod, Eitan Melamed, Moshe Gottlieb, Yoav Tsori
cond-mat.soft physics.chem-ph