1. Department of Pharmaceutics and Bioengineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
2. College of Chemistry and Environment Protection Engineering, Southwest Minzu University, Chengdu 610041, P. R. China
3. Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu 610041, P. R. China