Fig. 2

Cytotoxicity assessments of the OX@Se-MnP and uptake of FITC-labeled Se-MnP by HCT116/DR cells. A Relative cell viabilities of HCT116/DR cells co-incubation with OX (20 μg/mL), Se-MnP (100 μg/mL) and OX@Se-MnP (120 μg/mL) for 48 h. B Relative cell viabilities of HCT116/DR cells after 24 h and 48 h co-incubation with OX@Se-MnP at varied concentrations. C Relative cell viabilities of HCT116/DR cells co-incubation with OX and OX@Se-MnP at varied concentrations after 24 h. D The images of CAM and PI stained HCT116/DR cells treated with PBS, OX (20 μg/mL), Se-MnP (100 μg/mL) and OX@Se-MnP (120 μg/mL) for 48 h. (Green fluorescence: Calcein AM representing living cells, red fluorescence: PI representing dead cells). E FITC-labeled Se-MnPs were incubated with HCT116/DR cells. After incubating for 2 h, 4 h, 8 h and 10 h, the cells were stained with DAPI and were observed by fluorescence microscope. Scale bar: D 100 μm, F 10 μm.**p < 0.01 and ***p < 0.001