UCLA

Developing chemical tools to detect and influence biological processes is a cornerstone of chemical biology. Here we combine two tools which rely on orthogonality– perfluorocarbons and multiplexed shortwave infrared fluorescence imaging– to track the biodistribution of nanoemulsions in real time in living mice. Drawing inspiration from fluorous and shortwave infrared (SWIR) fluorophore development, we prepared two SWIR-emissive, fluorous-soluble chromenylium polymethine dyes. These are the most red-shifted fluorous fluorophores– “fluorofluorophores”– to date. After characterizing the dyes, their utility was demonstrated by tracking perfluorocarbon nanoemulsion biodistribution in vivo. Using an excitation-multiplexed approach to visualize two variables simultaneously, we gained insight into the importance of size and surfactant identity on biodistribution.Graphical AbstractFluorofluorophores (fluoro references to fluorine and fluorescence) are chemical tools to study perfluorocarbons. To understand the biodistribution of perfluorocarbons in animals, fluorofluorophores that emit past 1000 nm are necessary. Here we describe the synthesis, characterization, and application of shortwave infrared (SWIR)-emissive fluorofluorophores towards understanding how to control the pharmacokinetics of perfluorocarbon nanoemulsions in mammals.