Fig 1.
Transmission electron microscopy images (TEM) and size distributions of PS nano-beads.
NPs were suspended in RPMI 1640 cell culture media supplemented with 5% (v/v) FBS and 1% (v/v) penicillin/streptomycin. TEM images (column 1) show non-functionalized (A and D), carboxylated (B and E) and aminated (C and F) polystyrene nanobeads (scale bars = 100 nm). Size distributions (column 2) of each nanobeads were determined by dynamic light scattering at t0 at room temperature (blue curves) and after 24h in an incubator at 37°C (green curves).
Table 1.
Zeta potential and polydispersity indexes of PS nanobeads.
Fig 2.
Cell index real-time monitoring of Calu-3 epithelial cells and THP-1 macrophages exposed to PS nanobeads.
Cell index real-time monitoring of Calu-3 epithelial cells and THP-1 macrophages are reported on column 1 and 2 respectively. One representative experiment among three independents experiments were carried out for 48h and cell indexes were normalized at time 0 to ensure non inter-wells variability prior to the addition of nanoparticles. Calu-3 epithelial cells and THP-1 differentiated macrophages were exposed 48 h to the three kinds of PS nanobeads, PS-NF (A and D), PS-COOH (B and E) and PS-NH2 (C and F).
Fig 3.
Fluorescence follow-up of Calu-3 cells and THP-1 macrophages exposed to PS nanobeads.
Total sum intensity of fluorescence performed by 24 h real-time video-microscopy follow-up on Calu-3 cells (A) and THP-1 macrophages (B) exposed to PS-NF (blue curve), PS-COOH (red curve) and PS-NH2 (green curve) nanobeads.
Fig 4.
Confocal microscopy images of Calu-3 cells and THP-1 macrophages exposed to PS-NH2 nanobeads.
Confocal microscopy images of Calu-3 cells are reported on (A) and in (B) for THP-1 macrophages. For both cell types, times of exposure are as follows: 1 (line 1), 2 (line 2), 4 (line 3) and 24 h (line 4). Cytoplasm staining (actin) is represented on column 1, nanobeads on column 2, DNA staining on column 3 and column 4 represents overlay of the three stainings. White arrows indicate nanobeads location on overlay images (column 4). White bars correspond to 10 μm.
Table 2.
Genotoxicity of PS nanobeads on Calu-3 cells and THP-1 macrophages.