Figure 4.

CLSM images of intracellular ¹O₂ generation in a) 4T1 cells and b) MCF‐7 cells measured by DCFH‐DA after treatment of the cells with PHHPEG₆ NFs at pH 7.4 and 6.3 with and without 660 nm laser irradiation (0.12 W cm⁻², 10 min). CLSM images of c) 4T1 cells and d) MCF‐7 cells stained with calcein‐AM/PI, incubated with PHHPEG₆ NFs at pH 7.4 and 6.3 with 660 nm laser irradiation (0.12 W cm⁻², 10 min). The concentration of PHHPEG₆ NFs used for 4T1 cells was 50 μg mL⁻¹, and for MCF‐7 cells 200 μg mL⁻¹ in a‐d. MTT assay of cell viability of e) 4T1 cells) and f) MCF‐7 cells with PHHPEG₆ NFs at different concentrations at pH 7.4 and 6.3, with and without 660 nm laser irradiation (0.12 W cm⁻², 10 min).