Light-gated nano-porous polymersomes from stereoisomer-directed self-assemblies

Capsules with holes in the walls exist in natural systems like virus capsids, and in biomimetic systems like immune-stimulating complexes vaccines and liposomes of phospholipids/surfactants mixtures. Structuring pores into stable membrane and controlling their opening are extremely useful for applications that require nano-pores as channels for material exchange and transportation. Polymersomes, which are stable and robust vesicles made of amphiphilic block copolymer, are good candidates for drug carriers or micro/nanoreactors. Engineering structure-inherent and light-gated nano-porous polymersomes is especially appealing, but still unexplored. Here we present these polymersomes made from a polymer including a tetraphenylethene (TPE) in its center. TPE is an emblematic fluorogen with aggregation-induced emission, which possesses two stereoisomers sensitive to photoisomerization. Trans-isomer of the polymer forms classical vesicles, cis-isomer forms cylindrical micelles, while trans/cis mixtures construct perforated vesicles with nano-pores. Under UV light, the classical polymersomes of trans-isomer can be perforated by its cis-counterpart generated from the photoisomerization.