1. Department of Regenerative Biomaterials, Radboud University Medical Center, Philips van Leydenlaan 25 6525 EX, Nijmegen, The Netherlands
2. CAM Bioceramics B.V., Zernikedreef 6 2333 CL, Leiden, The Netherlands
3. Research Center for Nano Biomaterials, Analytical & Testing Center, Sichuan University 610064 Chengdu, China