The Janus Facet of Nanomaterials

Figure 1

In vitro cellular uptake of fluorophore dye-conjugated anionic (G4.5-COONa) and cationic (G5-NH₂) polyamidoamine (PAMAM) dendrimers. Confocal laser microscope images were taken after 1 h incubation of hepatocytes (a and c) and Kupffer cells (b) with PAMAM dendrimers. The anionic G4.5-COONa dendrimer was conjugated with 5(6)-TAMRA cadaverine HCl salt while the cationic G5-NH₂ dendrimer was coupled with 5(6)-TAMRA NHS ester as fluorescent dyes. Following 1 h of incubation, the anionic dendrimer expanded in the cytoplasm of the Kupffer cells, while it was retained in the plasma membrane of the hepatocytes. The uptake of the cationic derivative by the hepatocytes was much more extensive compared to the anionic one.

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(b)

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