Asst. Prof. Nuno Basilio, Departamento de Química, Campus de Caparica, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa

"Design Principles for Light-Responsive High-Affinity Host–Guest Systems in Water"

Photoswitchable host–guest pairs underpin a wide range of light-controlled molecular functions, including sol–gel transitions, photopharmacology, active transport of ions and molecules, light-powered molecular machines, and many other stimuli-responsive systems. Despite the rapid expansion of photoresponsive host–guest chemistry, the rational design of complementary binding pairs that combine high affinity, selectivity, and efficient photoswitching in aqueous environments remains a major challenge.
Over the past several years, our group has contributed to the discovery of new light-responsive host–guest complexes based on cucurbituril macrocycles that exhibit exceptional affinity and selectivity in water, together with enhanced photoswitching performance.[1–5] In this presentation, I will provide an overview of our work in this area and highlight recent advances in the development of exceptionally efficient host–guest systems incorporating diarylethene and diazocine photoswitches.

References
[1] N. Basílio, U. Pischel, “Drug Delivery by Controlling a Supramolecular Host-Guest Assembly with a Reversible Photoswitch” Chem. - A Eur. J. 2016, 22, 15208–15211.
[2] M. A. Romero, N. Basílio, A. J. Moro, M. Domingues, J. A. González-Delgado, J. F. Arteaga, U. Pischel, “Photocaged Competitor Guests: A General Approach Toward Light-Activated Cargo Release From Cucurbiturils” Chem. - A Eur. J. 2017, 23, 13105–13111.
[3] P. Ferreira, B. Ventura, A. Barbieri, J. P. Da Silva, C. A. T. Laia, A. J. Parola, N. Basílio, “A Visible–Near‐Infrared Light‐Responsive Host–Guest Pair with Nanomolar Affinity in Water” Chem. – A Eur. J. 2019, 25, 3477–3482.
[4] A. Zubillaga, P. Ferreira, A. J. Parola, S. Gago, N. Basílio, “pH-Gated photoresponsive shuttling in a water-soluble pseudorotaxane” Chem. Commun. 2018, 54, 2743–2746.
[5] M. Colaço, J. Ewert, J.-S. von Glasenapp, U. Pischel, R. Herges, N. Basílio, “Diazocines as Guests of Cucurbituril Macrocycles: Light-Responsive Binding and Supramolecular Catalysis of Thermal Isomerization” J. Am. Chem. Soc. 2025, 147, 734–745.

Contact person:
Univ.-Prof. Davide Bonifazi - davide.bonifazi@univie.ac.at
Alma Krpuljevic-Hanic - alma.krpuljevic-hanic@univie.ac.at
Yvonne Walter – institute.orgchem@univie.ac.at