Synthesis and Evaluation of [18F]-Ammonium BODIPY Dyes as Potential Positron Emission Tomography Agents for Myocardial Perfusion Imaging

Recently, we demonstrated the potential of a [F-18]-trimethylammonium BODIPY dye for cardiac imaging. This is the first example of the use of the [F-18]-ammonium BODIPY dye for positron emission tomography (PET) myocardial perfusion imaging (MPI). In this report, we extend our study to other ammonium BODIPY dyes with different nitrogen substituents. These novel ammonium BODIPY dyes were successfully prepared and radiolabeled by the SnCl4-assisted F-18-F-19 isotopic exchange method. The microPET results and the biodistribution data reveal that nitrogen substituent changes have a significant effect on the in vivo and pharmacological properties of the tracers. Of the novel [F-18]-ammonium BODIPY dyes prepared in this work, the [F-18]-dimethyl-ethylammonium BODIPY is superior in terms of myocardium uptake and PET imaging contrast. These results support our hypothesis that the ammonium BODIPY dyes have a great potential for use as PET/optical dual-modality MPI probes.