Photocrosslinked and pH-switchable Soft Polymer Nanocapsules from Polyglycidyl Ethers

ChemRxiv

Abstract

Soft polymer nanocapsules and microgels, which can adapt their shape and at the same time sequester and release molecular payloads in response to an external trigger, are a challenging complement to vesicular structures like polymersomes. In this work we report the synthesis of such capsules by photocrosslinking of coumarin-substituted polyglycidyl ethers, which we prepared by Williamson etherification of epichlorohydrin (ECH) repeating units with 7-hydroxycoumarin in copolymers with tert-butyl glycidyl ether (tBGE). To control capsule size, we employed the prepolymers in an o/w miniemulsion, where they formed a gel layer at the interface upon irradiation at 365 nm by [2π+2π] photodimerization of the coumarin groups. Upon irradiation at 245 nm, the reaction could be reversed and the gel wall could be repeatedly disintegrated and rebuilt. We further demonstrated (i) reversible hydrophilization of the gels by hydrolysis of the lactone rings in coumarin dimers as a mechanism to manipulate the permeability of the capsules, and (ii) binding functional molecules as amides. Together with the possibility to hydrolyze the tert-butyl ether group we demonstrate a remarkable versatility of such nanogels for their use as a carrier system.

Authors 8

1. Pascal M. Jeschenko Aachen DWI - Leibniz Institute for Interactive Materials

   Max Planck Institute for Medical Research · DWI – Leibniz Institute for Interactive Materials · Max Planck School Matter to Life

   Affiliation as printed

   DWI - Leibniz-Institute for Interactive Materials

   Max Planck Institute for Medical Research

   Max Planck School Matter to Life

2. Marcel van Dongen Aachen DWI - Leibniz Institute for Interactive Materials

   DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI - Leibniz-Institute for Interactive Materials

3. Jonas C. Rose Aachen DWI - Leibniz Institute for Interactive Materials

   DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI - Leibniz-Institute for Interactive Materials

4. Dominic Schäfer Aachen Institute of Inorganic Chemistry

   RWTH Aachen University

   Affiliation as printed

   Institute of Inorganic Chemistry (IAC), RWTH Aachen University

5. Michael Brüns

   Karlsruhe Institute of Technology

   Affiliation as printed

   Institute for Applied Materials and Karlsruhe Nano Micro Facility, Karlsruhe Institute of Technology

6. Sonja Herres‐Pawlis Aachen Institute of Inorganic Chemistry

   RWTH Aachen University

   Affiliation as printed

   Institute of Inorganic Chemistry (IAC), RWTH Aachen University

7. Helmut Keul Aachen DWI - Leibniz Institute for Interactive Materials

   DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI - Leibniz-Institute for Interactive Materials

8. Martin Möller Aachen DWI - Leibniz Institute for Interactive Materials Institute for Technical and Macromolecular Chemistry

   DWI – Leibniz Institute for Interactive Materials · Max Planck School Matter to Life · RWTH Aachen University

   Affiliation as printed

   DWI - Leibniz-Institute for Interactive Materials

   Institute for Technical and Macromolecular Chemistry (ITMC), RWTH Aachen University

   Max Planck School Matter to Life