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

## TL;DR

This paper introduces self-destructing nanoparticles that change shape and release cargo quickly when exposed to UV light, offering new possibilities for controlled delivery systems.

## Contribution

The novelty lies in creating Janus dendrimers that rapidly self-degrade and morph under UV light, enabling on-demand release of encapsulated molecules.

## Key findings

- SIJDs self-assemble into spherical nanoparticles in water.
- UV light triggers rapid shape transformation from spheres to crescents within minutes.
- The degradation pathway enables controlled release of encapsulated cargo.

## Abstract

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.

Self‐immolative Janus dendrimers assemble into spherical nanoparticles with solid cores. Upon irradiation, rapid end‐to‐end depolymerization triggers a unique degradation pathway from spheres to crescents within minutes, enabling on‐demand release of encapsulated cargo. This rapid photodegradation provides assemblies with predefined lifetimes and points toward dynamic supramolecular states for stimuli‐responsive applications.