Hydrotropic solutions

Hydrotropes are a class of amphiphilic molecules that cannot form well organized structures, such as micelles, in water but do increase the aqueous solubility of organic molecules. Often strong synergistic effects are observed when hydrotropes are added to aqueous surfactant or polymer solutions. Recent studies regarding the effects of hydrotropes on phase behavior, aggregation, surface tension, viscosity, solubility, and microstructure formation are reviewed. Novel applications of hydrotropes as molecular probes and for controlled release of pharmaceuticals are also discussed.