Perfluoro-tert-butanol: a cornerstone for high performance fluorine-19 magnetic resonance imaging

Abstract

As a versatile quantification and tracking technology, ¹⁹F magnetic resonance imaging (¹⁹F MRI) provides quantitative “hot-spot” images without ionizing radiation, tissue depth limit, and background interference. However, the lack of suitable imaging agents severely hampers its clinical application. First, because the ¹⁹F signals are solely originated from imaging agents, the relatively low sensitivity of MRI technology requires high local ¹⁹F concentrations to generate images, which are often beyond the reach of many ¹⁹F MRI agents. Second, the peculiar physicochemical properties of many fluorinated compounds usually lead to low ¹⁹F signal intensity, tedious formulation, severe organ retention, etc. Therefore, the development of ¹⁹F MRI agents with high sensitivity and with suitable physicochemical and biological properties is of great importance. To this end, perfluoro-tert-butanol (PFTB), containing nine equivalent ¹⁹F and a modifiable hydroxyl group, has outperformed most perfluorocarbons as a valuable building block for high performance ¹⁹F MRI agents. Herein, we summarize the development and application of PFTB-based ¹⁹F MRI agents and analyze the strategies to improve their sensitivity and physicochemical and biological properties. In the context of PFC-based ¹⁹F MRI agents, we also discuss the challenges and prospects of PFTB-based ¹⁹F MRI agents.