A Superfluorinated Molecular Probe for Highly Sensitive <i>in Vivo</i>¹⁹F‑MRI

19F-MRI offers unique opportunities to image diseases and track cells and therapeutic agents in vivo. Herein we report a superfluorinated molecular probe, herein called PERFECTA, possessing excellent cellular compatibility, and whose spectral properties, relaxation times, and sensitivity are promising for in vivo19F-MRI applications. The molecule, which bears 36 equivalent 19F atoms and shows a single intense resonance peak, is easily synthesized via a simple one-step reaction and is formulated in water with high stability using trivial reagents and methods.