Fig. 2.

Uptake of ME (A), MP (B) and PL (C) lipid nanocapsules in SF (horizontal gray lines) and cDMEM medium (horizontal lines) by A549 cells as determined by flow cytometry. Error bars are the standard deviation of the mean cell fluorescence intensity averaged over 3 replicates. For all the types of nanocapsules, the uptake in SF was higher than in complete medium. Cells exposed to several types of particles for up to 24 h, changed their phenotype and lost cell adhesion, which is indicative of cell damage, due to the strong adhesion of bare nanoparticle surfaces to the cell membrane. In fact, we could not determine the uptake by flow cytometry of EP nanoparticles in SF because they seriously damaged cells already after short exposure times.