Click-Ready Perfluorocarbon Nanoemulsion for ¹⁹F MRI and Multimodal Cellular Detection

We describe an in vivo imaging probe platform that is readily modifiable to accommodate binding of different molecular targeting moieties and payloads for multimodal image generation. In this work, we demonstrate the utility of perfluorocarbon (PFC) nanoemulsions incorporating dibenzocyclooctyne (DBCO) by enabling postemulsification functionalization via a click reaction with azide-containing ligands. The addition of DBCO-lipid to the surfactant in PFC nanoemulsions did not affect nanoemulsion size or nanoemulsion stability. As proof-of-concept, fluorescent dye-azides were conjugated to PFC nanoemulsions, demonstrating the feasibility of functionalization the by click reaction. Uptake of the fluorescent PFC by macrophages was demonstrated both in vitro in cultured macrophages and in situ in an acute inflammation mouse model, where fluorescence imaging and ¹H/¹⁹F magnetic resonance imaging (MRI) were used for in vivo detection. Overall, these data demonstrate the potential of PFC nanoemulsions incorporating DBCO as a versatile platform for generating functionalized probes.