1. Center for Molecular Imaging and Nuclear Medicine; School for Radiological and Interdisciplinary Sciences (RAD-X); Soochow University; Suzhou 215123 P. R. China
2. Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions; Suzhou 215123 P. R. China
3. Institute of Chemistry; Chinese Academy of Sciences, Bei Yi Jie 2, Zhongguancun; Beijing 100190 P. R. China