1. Biomaterials and Polymer Science, Department of Bio- and Chemical Engineering, TU Dortmund, Emil-Figge-Str. 66, 44227 Dortmund, Germany
2. BG University Hospital Bergmannsheil Bochum/Surgical Research, Ruhr University Bochum, Buerkle-de-la-Camp-Platz 1, D-44789 Bochum, Germany
3. Institute for Physical Chemistry, University of Muenster, Corrensstrasse 30, 48149 Muenster, Germany