Supporting Information for Fluorescent microspheres for one-photon and two-photon imaging of mesenchymal stem cells

a School of Radiation Medicine and Protection and School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Medical College of Soochow University, Suzhou, Jiangsu 215123, China. b Department of Radiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China c Key Laboratory for Nano-Bio Interface Research, Division of Nanobiomedicine, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, Jiangsu 215123, China d Department of Oncology, The Affiliated Changzhou No.2 People's Hospital With Nanjing Medical University, Changzhou, Jiangsu 213100, China