1. School of Materials Science and Engineering; South China University of Technology; Guangzhou 510641 China
2. Nation Engineering Research Centre for Tissue Restoration and Reconstruction; Guangzhou 510006 China
3. Guangdong Province Key Laboratory of Biomedical Engineering; South China University of Technology; Guangzhou 510006 China
4. Department of Anatomy; Guangdong Provincial Key Laboratory of Medical Biomechanics; Southern Medical University; Guangzhou 510515 China
5. Department of Chemistry & Biochemistry; Stephenson Life Sciences Research Center; Institute for Biomedical Engineering; Science and Technology; University of Oklahoma; 101 Stephenson Parkway, Room 3310 Norman OK 73019-5300 USA
6. School of Materials Science and Engineering; Zhejiang University; Hangzhou Zhejiang 310027 China