Light‐Gated Amine Exchange in Diarylethene‐Crosslinked Microgels

Angewandte Chemie International Edition, vol. 64, pp. e202510141

Abstract

Abstract The functionalization of microgels with photoswitchable moieties enables the construction of multi‐responsive systems, which are highly interesting for biological applications, for example, in drug delivery. Controlling the reversible uptake of functional molecules, however, remains a major challenge. To address this, we developed a novel aniline‐type diarylethene (DAE) crosslinker and prepared a series of corresponding poly( N ‐vinylcaprolactam)‐based microgels with varying degrees of DAE crosslinker. Upon UV light irradiation, the aniline (and thus enamine) motif of the DAE is converted to its imine form, thus allowing for reversible exchange with primary amines. Irradiating the DAE with blue light covalently locks the equilibrium and traps the amine in the microgels. The light‐controlled covalent binding of fluorinated, hydrophobic, and hydrophilic amine derivatives was proven by dynamic light scattering and 19 F NMR spectroscopy. Importantly, the impact of photoisomerization and amine binding on microgel properties was investigated and we were able to remotely control size as well as temperature and pH responsiveness by light. Overall, this study demonstrates optically gated uptake and release of functional amines in multi‐responsive microgels and highlights their potential biological applications.

Authors 5

1. Kevin Broi Aachen DWI - Leibniz Institute for Interactive Materials Institute of Technical and Macromolecular Chemistry

   RWTH Aachen University · DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI–Leibniz Institute for Interactive Materials RWTH Aachen University Forckenbeckstr. 50 52074 Aachen Germany

   Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 2 52074 Aachen Germany

   Both authors contributed equally to this work

   Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany

2. Frédéric Grabowski Aachen DWI - Leibniz Institute for Interactive Materials Institute of Technical and Macromolecular Chemistry

   RWTH Aachen University · DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI–Leibniz Institute for Interactive Materials RWTH Aachen University Forckenbeckstr. 50 52074 Aachen Germany

   Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 2 52074 Aachen Germany

   Both authors contributed equally to this work

   Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany

3. Jannick Dörr Aachen DWI - Leibniz Institute for Interactive Materials Institute of Technical and Macromolecular Chemistry

   RWTH Aachen University · DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI–Leibniz Institute for Interactive Materials RWTH Aachen University Forckenbeckstr. 50 52074 Aachen Germany

   Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 2 52074 Aachen Germany

   Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany

4. Andrij Pich corresponding Aachen DWI - Leibniz Institute for Interactive Materials Institute of Technical and Macromolecular Chemistry

   RWTH Aachen University · DWI – Leibniz Institute for Interactive Materials · Maastricht University

   Affiliation as printed

   Aachen Maastricht Institute for Biobased Materials Maastricht University Geleen 6167 RD The Netherlands

   DWI–Leibniz Institute for Interactive Materials RWTH Aachen University Forckenbeckstr. 50 52074 Aachen Germany

   Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 2 52074 Aachen Germany

   DWI–Leibniz Institute for Interactive Materials RWTH Aachen University Forckenbeckstr. 50 52074 Aachen Germany

   Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany

5. Stefan Hecht corresponding Aachen DWI - Leibniz Institute for Interactive Materials Institute of Technical and Macromolecular Chemistry

   RWTH Aachen University · DWI – Leibniz Institute for Interactive Materials · Humboldt-Universität zu Berlin

   Affiliation as printed

   Center for the Science of Materials Berlin Humboldt University of Berlin Zum Großen Windkanal 2 12489 Berlin Germany

   DWI–Leibniz Institute for Interactive Materials RWTH Aachen University Forckenbeckstr. 50 52074 Aachen Germany

   Department of Chemistry, Humboldt University of Berlin Brook‐Taylor‐Str. 2 12489 Berlin Germany

   Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 2 52074 Aachen Germany

   DWI–Leibniz Institute for Interactive Materials RWTH Aachen University Forckenbeckstr. 50 52074 Aachen Germany

   Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany