1. Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 6, FI-33720 Tampere, Finland
2. Department of Chemistry, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland
3. Biomaterial Processing and Products, VTT Technical Research Centre of Finland Ltd., Tietotie 4E, 02044 Espoo, Finland
4. Department of Electronics and Nanoengineering, Aalto University, Maarintie 13, 02150 Espoo, Finland