Fig. 3

Cellular uptake and apoptosis analysis in SW620 tumor cells. (a) Quantitative determination of cell uptake amounts for free DOX, DS NPs and SC@DS NPs at 2 and 4 h incubation, respectively. (b) Apoptosis level of SW620 cells after being treated with D/S, DS NPs, SC and SC@DS NPs, respectively. (c) The caspase-9 and cleaved-caspase-3 protein levels of SW620 cells and (d) semi-quantitative analysis of different groups. (e) The bax/bcl-2 ratio analysis