1. Institute of Biomedical Engineering, Boğaziçi University, Rasathane Street, Kandilli, İstanbul34684, Turkey
2. Department of Materials Science and Engineering, Institute of Biomaterials, University of Erlangen-Nuremberg, 91058Erlangen, Germany
3. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte, Escuela Politécnica Superior, Universidad de Sevilla, 41011Seville, Spain