In vivo "hot spot" MR imaging of neural stem cells using fluorinated nanoparticles.

To optimize (19)F MR tracking of stem cells, we compared cellular internalization of cationic and anionic perfluoro-15-crown-5-ether (PFCE) nanoparticles using cell culture plates with different surface coatings. The viability and proliferation of anionic and cationic PFCE-labeled neural stem cells (NSCs) did not differ from unlabeled cells. Cationic PFCE nanoparticles ((19)F T1/T2 = 580/536 ms at 9.