In any given solvent, an amphiphile is a molecule that comprises both soluble and insoluble parts. If the solvent is water, the two fragments are hydrophobic and hydrophilic, respectively. Such a dual nature drives one the most exquisite example of self-assembly. Amphiphiles can assemble in water into either spherical or cylindrical micelles or membranes. These, in turn, can further assemble into liquid crystals gels. Membranes formed by natural amphiphiles (e.g. phospholipids), in particular, are a critical component of biological organisation. They set the limits within and between cells forming enclosed compartments critical to maintaining the delta chemical potentials to feed life.
Membranes have to avoid contact between their edges and water, and this drives their deformation to form enclosed structures known as vesicles typically spherical to minimise surface area.
Amphiphiles can be block copolymers made of hydrophilic and hydrophobic polymers joined together. The polymeric nature of the copolymers imposes two unique features to amphiphilic copolymer membranes: (i) hydrophobic entanglement and (ii) hydrophilic brush-like configuration. Such unique features make copolymer vesicles also known as polymersomes very different from their low molecular counterparts. Entanglement (for low Tg polymers) means high mechanical deformability and toughness. At the same time, the brush-like configuration enables to surround the polymersome with a dense hydrophilic layer that controls both colloidal stability and interaction with its environment.
A large portion of our research activities are devoted to polymersomes, vesicles made of copolymers, and their unique properties. We study polymersomes, as well as their natural counterparts liposomes. We are very interested in vesicle formation, properties and application in drug delivery, nanoreactors and origin-of-life science.
We also combine polymer synthesis with self-assembly to create porous cross-linked materials with porosity, surface chemistry, surface topology, topography, mechanical properties are tuned by supramolecular interactions. We have adapted the synthesis of porous foams prepared by high internal phase emulsion (HIPE) using amphiphilic copolymers that act as surfactants during the HIPE process.