Figure 2. Cellular uptake of Dox, doxorubicin-loaded graphene oxide (Dox-GO) or angiopep-2 polypeptide-modified and doxorubicin-loaded graphene oxide (ANG-Dox-GO) by U87 MG cells. Confocal images of U87 MG cells treated with Dox, Dox-GO or ANG-Dox-GO at 10 μg/mL of Dox for 0.5 and 1 h.