Fig. 4. Determination of the therapeutic capacity of SPP/GO and IR780-SPP/GO. Schematic representation of the procedure used to evaluate the phototherapeutic effect of SPP/GO or IR780-SPP/GO towards MCF-7 cells (A). Therapeutic effect mediated by SPP/GO and IR780-SPP/GO towards MCF-7 cells without (w/o NIR) and with NIR (w/NIR) laser irradiation (808 nm, 1.7 W cm ⁻², 8 min) (B). K⁻ w/o NIR represents the negative control, while K⁻ w/NIR represents cells solely exposed to NIR light. Data represents mean ± S.D., n = 5, (*p < 0.01, **p < 0.0001), ns = non-significant. CLSM images of MCF-7 cells stained with Calcein-AM/PI after exposure to SPP/GO or IR780-SPP/GO w/o NIR (C) or w/NIR laser irradiation (808 nm, 1.7 W cm ⁻², 8 min) (D). Medium w/o NIR represents the control for live cells, while medium w/NIR represents cells solely exposed to NIR light. Green channel: Calcein-AM; red channel: PI. Scale bars correspond to 50 μm.