Fig. 5
From: Photosensitizing deep-seated cancer cells with photoprotein-conjugated upconversion nanoparticles
NIR-induced cytotoxic effect of UCNP-KR-LP on various cancer cell lines. a Representative confocal images of 5 cancer cell lines (MCF-7, SK-BR-3, MDA-MB-231, MCF-10 A, and U-87MG) with SG/DAPI double staining after treatment with CS-UCNP-KR (top) or CS-UCNP-KR-LP (bottom) followed by NIR irradiation at 980 nm for 30 min. Blue, green, and red indicate DAPI, SG, and KR, respectively. Scale bar = 50 μm. b Quantitative FL analysis of SG intensity from confocal images in three independent experiments. c MTT assay of the cell viability of 5 cancer cell lines. The cells were treated with unmodified or modified CS-UCNPs (every 200 µg/mL) followed by NIR irradiation at 980 nm (1 W/cm2 for 30 min). The significant difference in cell viability between CS-UCNP-KR and CS-UCNP-KR-LP was evaluated (***P < 0.001, n = 3, one-way ANOVA with post-hoc Tukey’s test). DAPI, 4′,6-diamidino-2-phenylindole; SG, SYTOX Green; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide