(276e) Peptide Surfactants (Pepfactants®) for Switchable Control of Foam and Emulsion Stability

We have developed a family of designed peptide surfactants (Pepfactants®) capable of stabilizing foams and emulsions in a stimuli-responsive manner, based on the reversible formation of a mechanically strong interfacial film. The Pepfactants® technology employs the reversible switching of a collection of weak bonds, meaning that unlike cleavable surfactants, the Pepfactants® are not covalently altered by the switching process, which can be repeated multiple times and is complete within seconds. Switching is achieved by a change in the bulk solution composition, such as a change in pH, or the addition or sequestering of metal ions. We have demonstrated the ability of Pepfactants® to both stabilise and, upon switching of solution conditions rapidly phase separate, emulsions of clean oils such as toluene and complex oils such as crude oil.

In addition to the unique reversible switching capability, Pepfactants® represent a novel class of surfactants with many properties superior to those of traditional emulsifying and foaming agents. Considerably smaller than proteins, peptide surfactants adsorb rapidly at interfaces and being both bioproduced and biodegradable, are more sustainable than chemical surfactants. Pepfactants® have the potential to yield a new class of industrially important, stimuli-responsive foams and emulsions.