Xi Zhang and colleagues from Tsinghua University have demonstrated the synthesis of a supramolecular amphiphile via a charge transfer (CT) interaction. The resulting self-assembled nanostructures can be tuned reversibly between irregular continuous aggregates and organized vesicles, in response to environmental redox stimulus. Compared to classical stimuli responsive systems - where the responsive group is covalently linked to the building blocks - this supramolecular amphiphile has the advantage of good reversibility and facile preparation. 

For years, the CT interaction has been shown to fabricate various supramolecular systems with vivid properties, such as molecular machines, solar cells and liquid crystals with high charge mobility. Zhang's group have also recently demonstrated that CT interactions can act as a driving force to induce self-assembly transformation from tubes to vesicles. The current work reported by Zhang takes this one step further, as stimuli responsive supramolecular nanostructures based on reversible charge transfer interactions is rarely reported. Zhang hopes that 'our work can develop a way of fabricating stimuli responsive nanostructures based on charge transfer complexes.'

Future work could potentially see these systems being developed for smart nanocontainers or nanoreactors, especially based on the supramolecular amphiphile concept. Zhang says 'it is anticipated that diversified self-assembled nanoscale materials in response to multiple stimuli can be further developed, thus developing new supramolecular soft materials.'

Emma Shiells