Stabilization of fluorocarbon emulsions by sugar-derived perfluoroalkylated surfactants and co-surfactants

Abstract

Fluorocarbon emulsions have considerable potential as injectable oxygen carriers (blood substitutes, in particular), contrast agents for diagnosis, and drug-delivery systems. One approach to reducing the interfacial tension which opposes the dispersion of fluorocarbons in water, and to contributing to the stabilization of their emulsions, is to use fluorophilic surfactants. Several families of perfluoroalkylated, sugar-derived surfactants with modular molecular structures, including maltosides, trehalose fatty acid monoesters, and glucose phosphate esters were investigated to this end. Relatively minor structural differences were found to cause widely different behaviors. Very stable emulsions of perfluorodecalin (FDC) and perfluorooctylbromide (PFOB, perflubron) were obtained with some of them; the neutral ones led to considerable synergistic stabilization of such emulsions when a polaxomer (Pluronic F-68) was used as the primary surfactant, while the anionic ones developed such a synergistic effect with egg-yolk phospholipids (EYP). Some also had a significant impact on particle sizes.