Investigation of the self-assembly processes and architectural diversity of photo-reversible supramolecular gels

Supramolecular gels are a class of soft materials formed by the self-assembly of small molecules, exhibiting versatile properties and responsiveness to external stimuli. Understanding their self-assembly mechanisms is crucial for designing functional materials with controlled behavior. This project is part of the LIGHTSUPGEL initiative, which aims to establish a rational methodology for developing truly photo-reversible supramolecular hydrogels and organogels. To achieve this, we propose SAXS experiments to investigate the self-assembly process of four photo-reversible supramolecular gelators under controlled light irradiation.

By exposing the samples to 365 nm and 455 nm light sources, we will induce reversible assembly/disassembly processes. The study will be conducted in different solvents and concentrations to explore a broad range of polarities and solubilities. SAXS data will provide insights into the type, size, and organization of the aggregates, which will be correlated with previous results obtained from state-of-the-art nanoscopy techniques. We expect distinct SAXS profiles for the sol and gel states, as well as for their intermediate state. Furthermore, we aim to track early-stage self-assembly dynamics, particularly changes in the fractal dimension during network formation. Finally, by comparing SAXS patterns before irradiation and after multiple trans–cis–trans cycles, we seek to determine whether the observed macroscopic reversibility arises from a true supramolecular reconstitution of the original system. These results will contribute to a deeper understanding of photo-responsive self-assembly and guide the design of advanced supramolecular materials.