1. Department of Materials, Imperial College London, London, UK
2. Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, People's Republic of China
3. Institut für Physik, Humboldt-Universität zu Berlin, Berlin, Germany
4. Institut für Weiche Materie und Funktionale Materialien, Helmholtz-Zentrum Berlin, Berlin, Germany
5. Multifunctional Biomaterials for Medicine, Helmholtz Virtual Institute, Teltow, Germany
6. Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany