1. Fraunhofer Institute for Silicate Research ISC; c/o University Hospital Würzburg; Chair of Tissue Engineering and Regenerative Medicine; Röntgenring 11 97070 Würzburg Germany
2. CellTool GmbH; Am Neuland 1 82347 Bernried Germany
3. Ludwig-Maximilians-University Munich; Faculty of Physics; Geschwister-Scholl-Platz 1 80539 München Germany
4. Micromod Partikeltechnologie GmbH; Friedrich-Barnewitz-Straße 4 18119 Rostock Germany