Figure 4
Particle-induced X-ray emission (PIXE) spectra and maps of P and Ti distribution. PIXE spectra displaying the regions of interest (between dashed lines) selected for mapping and quantification of P and Ti content, on Caco-2 monoculture (A) and Caco-2/HT29-MTX co-culture (B). Chemical element distribution in the Caco-2 monoculture (C-E), Caco-2/HT29-MTX co-culture (F-H) and the Caco-2/RajiB co-culture (I-K), exposed to 50 μg/mL TiO2-NPs for 24 h: distribution of phosphorous (P) (C, F, I) and of titanium (Ti) (D, G, J), merge of P and Ti distribution maps (E, H, K).