Cytotoxicity of mitochondrial-targeting silica-coated manganese oxide nanoparticles

The mitochondrion is a promising target for diagnosis and therapy. Mitochondrial-targeting silica-coated manganese oxide nanoparticles(Mn O@Si O2-PPh3+ NPs) were successfully synthesized to explore the mitochondrial cytotoxicity of nanoparticles. The mitochondrial targeting property was confirmed by a laser scanning confocal microscopy experiment. Even after incubation for only 4 h, the cytotoxicity of Mn O@Si O2-PPh3+ NPs against cancer cells was obvious; the ATP content was significantly decreased to 40%; and the mitochondrial membrane potential was depleted. All of these results indicated the collapse of mitochondrial function and the start of a cell apoptosis pathway. Our findings suggest that mitochondrial-mediated apoptosis could be strengthened by targeting to the subcellular compartment.