Poly(glycerol) Used for Constructing Mixed Polymeric Micelles as <i>T</i><sub>1</sub> MRI Contrast Agent for Tumor-Targeted Imaging Yi Cao Min Liu Kunchi Zhang Guangyue Zu Ye Kuang Xiaoyan Tong Dangsheng Xiong Renjun Pei 10.1021/acs.biomac.6b01437.s001 https://acs.figshare.com/articles/journal_contribution/Poly_glycerol_Used_for_Constructing_Mixed_Polymeric_Micelles_as_i_T_i_sub_1_sub_MRI_Contrast_Agent_for_Tumor-Targeted_Imaging/4282169 There was much interest in the development of nanoscale delivery vehicles based on polymeric micelles to realize the diagnostic and therapeutic applications in biomedicine. Here, with the purpose of constructing a micellar magnetic resonance imaging (MRI) contrast agent (CA) with well biocompatibility and targeting specificity, two types of amphiphilic diblock polymers, mPEG–PG­(DOTA­(Gd))-<i>b</i>-PCL and FA-PEG-<i>b</i>-PCL, were synthesized to form mixed micelles by coassembly. The nanostructure of the resulting micellar system consisted of poly­(caprolactone) (PCL) as core and poly­(glycerol) (PG) and poly­(ethylene glycol) (PEG) as shell, simultaneously modified with DOTA­(Gd) chelates and folic acid (FA), which afforded functions of MRI contrast enhancement and tumor targeting. The mixed micelles in aqueous solution presented a hydrodynamic diameter of about 85 nm. Additionally, this mixed micelles exhibited higher <i>r</i><sub>1</sub> relaxivity (14.01 mM<sup>–1</sup> S<sup>1–</sup>) compared with commercial Magnevist (3.95 mM<sup>–1</sup> S<sup>1–</sup>) and showed negligible cytotoxicity estimated by WST assay. In vitro and in vivo MRI experiments revealed excellent targeting specificity to tumor cells and tissue. Furthermore, considerably enhanced signal intensity and prominent positive contrast effect were achieved at tumor region after tumor-bearing mice were intravenously injected with the mixed micelles. These preliminary results indicated the potential of the mixed micelle as <i>T</i><sub>1</sub> MRI CA for tumor-targeted imaging. 2016-11-21 00:00:00 signal intensity PG vivo MRI experiments WST assay amphiphilic diblock polymers PCL T 1 MRI CA micelle DOTA MRI contrast enhancement tumor-targeted imaging folic acid Tumor-Targeted Imaging FA PEG Constructing Mixed Polymeric Micelles hydrodynamic diameter 85 nm tumor cells contrast agent nanoscale delivery vehicles micellar system tumor-bearing mice tumor region FA-PEG T 1 MRI Contrast Agent resonance imaging contrast effect