Electron micrographs of brain endothelial cells with glucose-coated gold nanoparticles.

<p>(a) hCMEC/D3 cells and (b) primary human brain endothelium 8 hours after application of glucose-nanoparticles to the apical surface. Nanoparticles are located between the basal plasma membrane and the transwell insert (arrows), for (b) the lower area is also magnified in the top left corner ×2. (c) A gold nanoparticle in the intercellular junction of hCMEC/D3 cells (arrow) 3 hours after application of nanoparticles to the apical surface (detailed magnification of the junction with nanoparticle is in the top left corner ×7). The nanoparticles are also seen in the cytosol and vesicles. (d) Detail of nanoparticles located in the cytosol and beneath the basal membrane. (e) Detail of nanoparticles in a vesicle. Scale bars = 500 nm.</p>