Fig. 4
In vitro cytotoxic effects and PDT effects of SPN-PT. A Cell viability of 143B, MG63 and 4T1 cells determined by MTT assays after SPN-PT incubation (blue) or SPN-PT+laser treatments (635 nm, 0.75 W cm−2, 5 min per well) (red). B Flow cytometry of 143B cells co-stained with Annexin V-FITC and PI after different treatments, from left to right: PBS, laser, SPN-PT (16 µg mL−1), SPN-PT and laser irradiation (16 µg mL−1) (635 nm, 0.5 W cm−2, 5 min). C Representative CLSM images of live and dead 143B cells received different treatments: PBS (first row), SPN-PT (16 µg mL−1) (second row), SPN-PT+laser (16 µg mL−1) (635 nm, 0.5 W cm−2, 5 min) (third row). Necrotic cell nuclei could be stained by PI in red, while live cells were only stained by Calcein-AM in green. Scale bar = 50 μm. D CLSM images of 1O2 generated by in 143B cells irradiated by 635 nm laser (0.5 W cm−2), with (down) or without (up) incubation of SPN-PT for different time. BF: bright field. Scale bar = 20 μm. Data were shown as mean ± SD, n ≥ 3