Anionic Surfactant Micelles in Deep Eutectic Solvents

Deep Eutectic Solvents (DES) are molecular mixtures similar to ionic liquids, having melting points below
room temperature. However instead of being a salt, the mixture contains two molecules with strong Hbonding that hinder formation of an ordered crystalline network. DES have low vapour pressure, adjustable
polarity, and tunable components which make them interesting as green solvents while being far less toxic
than typical ionic liquids. They are currently being extensively explored for extraction of active species from
biomass and solubilisation of therapeutic agents for dermal delivery. These applications require formulation
using DES in emulsions and gels, requiring surfactants to stabilise DES-oil or DES-water interfaces and to
understand the surfactant phase behaviour in bulk solution, in order to control factors such as viscosity and
shear thinning behaviour. While a few surfactants have been previously studied in DES, these have so far
been restricted to model surfatants and in the cas of anionic surfactants this has been limited to species
with sulphur containing headgroups. Here we wish to study the bulk solution self-assembly of two anionic
surfactants that have different headgroup chemistries to determine how they interact with DES and the
morphologies of micelles formed by these surfactants in these novel solvents.