Fluoropolymer-Gadolinium(III) Hybrids for Photoactivatable Dual-Mode -Weighted H MRI and F MRI Contrast Agents.

Multimodal imaging probes play a crucial role in overcoming the limitations associated with single-mode imaging for clinical medical diagnosis. This study focuses on the development of a photoresponsive fluorine-containing water-soluble polymer () through RAFT polymerization. Subsequently, a polymer-gadolinium(III) hybrid () dual-modal probe capable of -weighted H MRI and F MRI was synthesized via postmodification of with a Gd-DOTA derivative. Under physiological conditions (pH = 7.4), the hybrids exhibit UV-activated F NMR/MRI and enhanced H MRI. The inclusion of Gd facilitates the acceleration of water molecule relaxation, leading to high-intensity H MRI contrast. Leveraging the paramagnetic relaxation enhancement (PRE) effect between fluorine atoms and Gd, the restoration of Gd-accelerated F relaxation enables precise photoactivation of F MRI signals, transitioning from the "OFF" to the "ON" state. This study provides an important reference for the development of hybrid systems that function as real-time diagnostic tools and offers controlled activation for multimodal imaging probes.