Figure 2

Cathepsin B confocal imaging in Ag-NP-treated Vero cells. A fluorescent substrate cleaved by active cathepsin B was detected using confocal microscopy in Vero cells treated with Ag-NPs or left untreated. a Negative control (Vero cells alone), b Positive control (Vero cells + CV-(FR)₂), c 10-nm uncoated Ag-NP 10 μg/ml, d 10-nm uncoated Ag-NP 50 μg/ml, e 10-nm PS-Ag-NP 10 μg/ml, f 10-nm PS-Ag-NP 50 μg/ml, g 25-nm uncoated Ag-NP 10 μg/ml, h 25-nm uncoated Ag-NP 50 μg/ml, i 25-nm PS-Ag-NP 10 μg/ml, j 25-nm PS-Ag-NP 50 μg/ml. Red fluorescent intensity was normalized to Vero cells exposed to the substrate (b). The table below represents a quantitative assessment of the confocal images as determined using a fluorescent plate reader. The values indicate the mean percent of control +/- SEM (n = 6).