A cyclodextrin surfactant for stable emulsions with an accessible cavity for host–guest complexation
Friederike Schlüter, Marlena M. Bela, Dana Glikman, Björn Braunschweig, Bart Jan Ravoo
Abstract
Although cyclodextrins (CDs) have been used as additives to small molecule surfactants, there are only a few examples of this cyclic oligosaccharide being used as a surfactant template. Herein, we present a novel ionic β-CD derivative that shows significant surface activity and stabilizes oil-in-water emulsions prepared with hexadecane as a model oil. The macrocyclic surfactant strongly reduces the oil-water surface tension with increasing concentration and shows a critical micelle concentration (CMC) around 5 mM. We demonstrate the stability of the oil-in-water emulsions and verify the possibility to address the emulsion droplet surface using molecular recognition of the β-CD cavity at the oil-water interface.