1. National Engineering Research Centre for Nanomedicine College of Life Science and Technology Huazhong University of Science and Technology 1037 Luoyu Road Wuhan 430074 P. R. China
2. Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medical Huazhong University of Science and Technology Wuhan 430074 P. R. China
3. School of Chemical and Biomedical Engineering Nanyang Technological University 70 Nanyang Drive Singapore 637457 Singapore
4. State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Soochow University Suzhou 215123 P. R. China
5. School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
6. Lee Kong Chian School of Medicine Nanyang Technological University Singapore 636921 Singapore