Fig. 5. NPs’ effect on the permeability of the alveolar capillary barrier on the chip. After 24 hours’ exposure to TiO2-NPs/ZnO-NPs, HPAEpiCs and HUVECs were washed with RPMI1640 medium and the FITC-dextran was added in the alveolar channel. The distribution of FITC-dextran on the chip was recorded by fluorescent microscopy at various time points (0 h, 6 h, 12 h, 24 h) to determine the permeability of the alveolar capillary barrier on the chip. A. Time-lapse images of FITC-dextran across the alveolar capillary barrier into the vessel channel with TiO2-NP treatment of different concentrations; B. statistical analysis of the permeability of the alveolar capillary barrier with TiO2-NP treatments; C. time-lapse images of FITC-dextran across the alveolar-capillary interface into the vessel channel with ZnO-NP treatment of different concentrations. Scale bar: 200 μm; D. statistical analysis of the permeability of the alveolar capillary barrier with ZnO NP treatments. * indicates p < 0.05; error bar: SD, n = 3.
