1. School of Materials Science and Engineering
2. Shanghai Jiao Tong University
3. Shanghai 200240
4. People's Republic of China
5. Shanghai Key Laboratory of Molecular Imaging
6. Shanghai University of Medicine and Health Sciences
7. Shanghai 201318
8. China
9. National Engineering Research Center for Nanotechnology
10. Shanghai 200241
11. P. R. China
12. Department of Radiology
13. Shanghai Renji Hospital
14. Shanghai Jiao Tong University School of Medicine
15. Shanghai 200127