1. State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
2. Department of Molecular and Medical Pharmacology, Crump Institute for Molecular Imaging (CIMI), California NanoSystems Institute (CNSI), University of California, Los Angeles, Los Angeles, California 90095-1770, United States
3. Department of Chemistry and Biochemistry, Department of Materials Science and Engineering, California NanoSystems Institute (CNSI), University of California, Los Angeles, Los Angeles, California 90095, United States
4. School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
5. Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
6. Department of Bioengineering, University of California, Los Angeles, Los Angeles, California 90095, United States
7. Department of Chemistry, Research Center for Sustainable Energy and Nanotechnology, Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University (NCHU), 145 Xingda Road, South Dist., Taichung 402, Taiwan
8. Department of Dermatology, Institute of Dermatology, Peking Union Medical College & Chinese Academy of Medical Sciences, 12 Jiangwangmiao Street, Xuanwu Dist., Nanjing 210042, China
9. Molecular Imaging Center, Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033-9061, United States