Stimuli-Responsive Polymers for Advanced 19F Magnetic Resonance Imaging: From Chemical Design to Biomedical Applications

Fluorine magnetic resonance imaging (19F MRI) is a rapidly evolving research area with a high potential to advance the field of clinical diagnostics. In this review, we provide an overview of the recent progress in the field of fluorinated stimuli-responsive polymers applied as 19F MRI tracers. These polymers respond to internal or external stimuli (e.g., temperature, pH, oxidative stress, and specific molecules) by altering their physicochemical properties, such as self-assembly, drug release, and polymer degradation. Incorporating noninvasive 19F labels enables us to track the biodistribution of such polymers. Furthermore, by triggering polymer transformation, we can induce changes in 19F MRI signals, including attenuation, amplification, and chemical shift changes, to monitor alterations in the environment of the tracer. Ultimately, this review highlights the emerging potential of stimuli-responsive fluoropolymer 19F MRI tracers in the current context of polymer diagnostics research.