Figure 7.

Analysis of HCT116 spheroids by confocal microscopy. Spheroids were treated for 5 h with 1 μM of RuL2 and subsequently irradiated with blue laser light (1 mW, 180 s). After 67 h post-treatment and irradiation in the drug-free medium, samples were stained with Hoechst 33258 dye, Calcein AM, and propidium iodide. The overlay of fluorescence channels was used to capture spheroid details. Bright-field images were obtained via phase contrast microscopy. Controls were irradiated with blue laser light (405 nm, 180 s), whereas RuL2-treated samples were irradiated with blue or red (405 or 650 nm, 180 s) laser light. Both laser lines used for irradiation were adjusted to a power of 1 mW. Scale bars in all panels represent 200 μm. The images represent maximal projections of 3D z-stacks and are representative of two independent experiments performed in triplicate; a quantitative evaluation of all experiments is given in Figure S19.