Fig. 4

Visualization of rGO by confocal laser microscopy and light microscopy. Representative confocal micrographs of hippocampus at the right cerebral hemisphere from: a vehicle-injected (control) rats showing none evidence of nanoparticles and b rGO-treated rats (1 h) showing differently-sized red dots that indicate the differential accumulation of nanoparticles, mainly in the dentate gyrus. Images were obtained at an excitation wavelength of 365 nm. c Bright field image of paraffin-embedded hippocampus (captured from the same region as a and b panels) from rats administered rGO (1 h): there were no morphologically detectable alterations. Hematoxilyn-eosin. Scale bars 20 μm (a, b) and 200 μm (c)