1. Department of Biomedical Engineering Research Center for Nano-biomaterials & Regenerative Medicine Shanxi Key Laboratory of Materials Strength & Structural Impact College of Biomedical Engineering Taiyuan University of Technology Taiyuan 030024 P. R. China
2. Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032 P. R. China
3. Laboratory of Biomaterial Surface and Interface Institute of New Carbon Materials Taiyuan University of Technology Taiyuan 030024 P. R. China