Figure 2

(a,b) Cellular uptake study. Cellular uptake was evaluated by measuring fluorescence intensity of PSs in (a) U87MG and (b) K562 cells. U87MG and K562 cells were incubated with the samples at various 700DX equivalent concentrations for 7 h before measuring the fluorescence intensity (Ex = 710 nm, Em = 780 nm). The results are expressed as mean ± S.D. (n = 6). Statistical analysis was performed using one-way ANOVA at 200 nM (*p < 0.01). (c) Subcellular distribution of PSs in U87MG cells. After 7 h incubation with PSs, fixed cells were observed using CLSM. The fluorescence of 700DX, Lysotracker Red DND-99, and Hoechst33342 are shown in green, red, and blue, respectively.