Figure 3.

a) Schematic illustration of O₂ generation and ¹O₂ production catalyzed by Au@Rh-CM. b) Fluorescence images of O₂ generation in MDA-MB-231 cells in a hypoxic setting (i.e., N₂ atmosphere) treated with: b1) no treatment, b2) H₂O₂, b3) Au@Rh-CM, and b4) Au@Rh-CM + H₂O₂. Experiments were repeated three times independently. c) Fluorescence images of singlet oxygen production in MDA-MB-231 cells in N₂ atmosphere treated with: c1) no treatment, c2) Au@Rh-ICG-CM in dark, c3) Au@Rh-CM under 808-nm laser irradiation, c4) Au@Rh-ICG-CM under 808-nm laser irradiation, and c5) Au@Rh-ICG-CM + H₂O₂ under 808-nm laser irradiation. Irradiation time was 3 min. Experiments were performed three times independently. d) Schematic illustration of MDA-MB-231 cells treated with Au@Rh-ICG-CM and laser irradiation in normoxia (air atmosphere) and hypoxia (N₂ atmosphere). e) Viability of MDA-MB-231 cells treated with Au@Rh-CM or Au@Rh-ICG-CM plus 808-nm laser irradiation (3 min) under normoxia (air atmosphere). Data are expressed as mean ± SD (n = 6). f) Viability of MDA-MB-231 cells treated with Au@Rh-CM, Au@Rh-ICG-CM, or Au@Rh-ICG-CM/H₂O₂ plus 808-nm laser irradiation (3 min) under hypoxia (N₂ atmosphere). Data are expressed as mean ± SD (n = 6). g) Fluorescence images of hypoxic MDA-MB-231 cells after different treatments: g1) no treatment in dark, g2) Au@Rh-ICG-CM in dark, g3) Au@Rh-CM under 808-nm laser irradiation, g4) Au@Rh-ICG-CM under 808-nm laser irradiation, and g5) Au@Rh-ICG-CM/H₂O₂ under 808 nm laser irradiation. Cells were stained live (green) with calcein (AM) and dead (red) with propidium iodide (PI). The irradiation time was 3 min. Experiments were repeated three times independently.