Liver metastasis (LM) remains a leading cause of cancer mortality, and conventional magnetic resonance imaging (MRI) is susceptible to physiological interference, which affects the diagnostic accuracy of LM. Fluorine-19 (¹⁹F) MRI offers a promising solution due to its negligible endogenous background, yet existing targeted probes face limitations in tumor heterogeneity and receptor variability. We developed a novel ¹⁹F MRI nanoparticles (EP-NPs) by coating perfluorocarbon nanoparticles (PFCE NPs) with exosomal membranes derived from HEK-293T cells. The hybrid platform combined the targeting capability of exosomes with the superiority of ¹⁹F MRI. Characterization included dynamic light scattering, transmission electron microscopy, and 19F nuclear magnetic resonance (NMR). In vitro cellular uptake was evaluated in BT-549 and NCI-H446 cells using confocal microscopy. In vivo targeting ¹⁹F MRI study was assessed in a BT-549 liver metastasis mouse model. Toxicity was tested via 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, serum biochemistry, and histopathology. EP-NPs exhibited a hydrodynamic diameter of 111.6 ± 8.2 nm, negative zeta potential (-20.50 mV), and stable ¹⁹F signal. Confocal imaging confirmed enhanced cellular uptake of EP-NPs compared to non-targeted PFCE NPs. In vivo, EP-NPs enabled precisely detection of LM with sustained ¹⁹F signal. Biodistribution revealed that EP-NPs accumulate in the liver and spleen, and toxicity assessments demonstrated no significant hepatorenal impairment or histological damage. EP-NPs integrate priorities of exosomes and ¹⁹F MRI achieve precise LM detection with high biocompatibility and prolonged circulation. This platform holds potential for clinical translation, overcoming limitations of conventional imaging agents.
Xu et al. (2026) studied this question.