1. Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 22, 4058 Basel, Switzerland
2. NCCR-Molecular Systems Engineering, BPR 1095, Mattenstrasse 24a, 4058 Basel, Switzerland
3. Group for Functionalized Biomaterials, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland