1. Laboratory of Molecular Imaging and Nanomedicine (LOMIN); National Institute of Biomedical Imaging and Bioengineering (NIBIB); National Institutes of Health; Bethesda MD 20892 USA
2. State Key Laboratory for Powder Metallurgy; Central South University; Hunan Changsha 410083 P. R. China
3. Department of Radiology; The Third Xiangya Hospital; Central South University; Changsha Hunan 410013 P. R. China
4. Laboratory of Cellular Imaging and Macromolecular Biophysics; National Institute of Biomedical Imaging and Bioengineering (NIBIB); National Institutes of Health; Bethesda MD 20892 USA
5. Center for Molecular Imaging and Translational Medicine; School of Public Health; Xiamen University; Xiamen Fujian 361005 P. R. China