Fig. 7
Ultrastructural detection of Co3O4-NPs in rat ventricular cardiomyocytes. Panels a and b: Transmission Electron Microscopic (TEM) images of a CTRL cardiomyocyte illustrating the regular distribution of mitochondria (Mit) and myofibrils (MF) and the scattered accumulation of small electrondense glycogen granules (*). Panels c-f: Co3O4-NPs (arrows) were detected within the mitochondria (Mit; c-d) and at the interface between mitochondria and myofibrils (MF; e-f) in cardiomyocytes exposed to 5 μg/ml (NPc5) and 50 μg/ml (NPc50) Co3O4-NPs, respectively. N: cardiomyocyte nucleus. Scale bars: 2 μm in a, c, d; 0.5 μm in b, d, f.