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Updated: Jan 23, 2026

Synthesis and Evaluation of a Ruthenium-based Mitochondrial Calcium Uptake Inhibitor
Published on: October 26, 2017
Dynamic Supramolecular Ruthenium-Based Gels Responsive to Visible/NIR Light and Heat
Ian Teasdale1, Sabrina Theis2, Aitziber Iturmendi1
1Institute of Polymer Chemistry, Johannes Kepler University Linz, Altenberger Straße 69, 4040, Linz, Austria.
Abstract:
A simple supramolecular crosslinked gel is reported with a photosensitive ruthenium bipyridine complex functioning as a crosslinker and poly(4-vinylpyridine) (P4VP) as a macromolecular ligand. Irradiation of the organogels in H2 O/MeOH with visible and NIR light (in a multiphoton process) leads to cleavage of pyridine moieties from the ruthenium complex breaking the cross-links and causing degelation and hence solubilization of the P4VP chains. Real-time (RT) photorheology experiments of thin films showed a rapid degelation in several seconds, whereas larger bulk samples could also be photocleaved. Furthermore, the gels could be reformed or healed by simple heating of the system and restoration of the metal-ligand crosslinks. The relatively simple dynamic system with a high sensitivity towards light in the visible and NIR region make them interesting positive photoresists for nano/micropatterning applications, as was demonstrated by writing, erasing, and rewriting of the gels by single- and multiphoton lithography.
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