1. Polymer Chemistry and Biomaterials Research Group, Department of Organic Chemistry; Ghent University; Krijgslaan 281/S4-Bis B-9000 Ghent Belgium
2. Department of Biomedical Engineering, 4 Colby Street; Tufts University; Medford MA 02155 USA
3. Department of Basic Medical Science; Histology Group; Ghent University; De Pintelaan 185 (6B3) 9000 Ghent Belgium
4. Advanced Concepts Team (ACT) European Space Agency; PPC-PF, Keplerlaan 1, PO Box 299 NL-2200 AZ Noordwijk The Netherlands
5. Department of Solid State Sciences; COCOON, Ghent University; Krijgslaan 281/S1 B-9000 Ghent Belgium
6. Department of Inorganic Chemistry; COMOC, Ghent University; Krijgslaan 281 S3 9000 Ghent Belgium