Polymer Mechanochemistry of Metal-Organic Cages in Supramolecular Chemistry

Dr. Bernd M. Schmidt, Heinrich-Heine-Universität Düsseldorf

My research group explores diverse facets of supramolecular chemistry, with a particular focus on mechanoresponsive supramolecular systems for the controlled release of non-covalently bound guests from aqueous solution. The mechanochemical liberation of cargo molecules from latent carrier polymers remains a challenge. In 2021, we introduced a versatile platform that employed a supramolecular coordination cage as a complex mechanophore. By integrating metal-mediated self-assembly of organic ligands into discrete nanoscopic architectures with polymer chains attached at each vertex, we achieved ultrasound-induced disassembly of cargo-loaded PdII6(TPT)4 cages, thereby enabling the release of nanoconfined guests. This concept was exemplified by the encapsulation and subsequent release of several unmodified, pharmaceutically active compounds. Beyond this, we have developed bifunctionalised bipyridines that facilitate the formation of metal–organic cage-based hydrogels, bridging supramolecular chemistry and soft matter.

In this talk, I will present a series of new systems that expand upon the Pd–N mechanophore concept, highlighting strategies for ultrasound activation of star-shaped supramolecular polymers and offering an outlook toward broader applications in responsive materials design.