Supramolecular Assemblies of Self‐Immolative Janus Dendrimers With Rapid Photodegradation Response

Advanced supramolecular assemblies with predefined lifetimes and rapid responses to stimuli are in high demand for applications such as biomedical delivery systems. However, such assemblies are rarely able to respond rapidly and completely to stimuli, with predictable changes in morphology. Here, we introduce monodisperse self-immolative Janus dendrimers (SIJDs) composed of hydrophilic oligo(ethylene glycol)-functionalized phenolic acid dendrons and hydrophobic monodisperse oligo(ethyl glyoxylate) chains having light-responsive end-groups. These SIJDs self-assemble into spherical nanoparticles in aqueous media. Upon ultraviolet (UV) light irradiation, the hydrophobic oligo(ethyl glyoxylate) units exhibit rapid end-to-end self-immolation within minutes. The depolymerization at the molecular level leads to a degradation pathway from spherical to crescent-shaped nanoparticles, which can be used for the rapid release of encapsulated molecules of interest.