Confocal Fluorescence Microscopy Studies of a Fluorophore-Labeled Dirhodium Compound: Visualizing Metal–Metal Bonded Molecules in Lung Cancer (A549) Cells

[Image: see text] The new dirhodium compound [Rh(2)(μ-O(2)CCH(3))(2)(η(1)-O(2)CCH(3))(phenbodipy)(H(2)O)(3)][O(2)CCH(3)] (1), which incorporates a bodipy fluorescent tag, was prepared and studied by confocal fluorescence microscopy in human lung adenocarcinoma (A549) cells. It was determined that 1 localizes mainly in lysosomes and mitochondria with no apparent nuclear localization in the 1–100 μM range. These results support the conclusion that cellular organelles rather than the nucleus can be targeted by modification of the ligands bound to the Rh(2)(4+) core. This is the first study of a fluorophore-labeled metal–metal bonded compound, work that opens up new venues for the study of intracellular distribution of dinuclear transition metal anticancer complexes.