Water-Soluble Chemically Precise Fluorinated Molecular Clusters for Interference-Free Multiplex F MRI in Living Mice.

Fluorine-19 magnetic resonance imaging (F MRI) is gaining widespread interest from the fields of biomolecule detection, cell tracking, and diagnosis, benefiting from its negligible background, deep tissue penetration, and multispectral capacity. However, a wide range of F MRI probes are in great demand for the development of multispectral F MRI due to the limited number of high-performance F MRI probes. Herein, we report a type of water-soluble molecular F MRI nanoprobe by conjugating fluorine-containing moieties with a polyhedral oligomeric silsesquioxane (POSS) cluster for multispectral color-coded F MRI. These chemically precise fluorinated molecular clusters are of excellent aqueous solubility with relatively high F contents and of single F resonance frequency with suitable longitudinal and transverse relaxation times for high-performance F MRI. We construct three POSS-based molecular nanoprobes with distinct F chemical shifts at -71.91, -123.23, and -60.18 ppm and achieve interference-free multispectral color-coded F MRI of labeled cells and . Moreover, F MRI reveals that these molecular nanoprobes could selectively accumulate in tumors and undergo rapid renal clearance afterward, illustrating their favorable behavior for biomedical applications. This study provides an efficient strategy to expand the F probe libraries for multispectral F MRI in biomedical research.