Fig. 4

Selective uptake of CL4 and/or Gint4.T-decorated Ir_en-AuSiO₂_Aptamer nanoplatforms in 3D heterotypic spheroids. A (left) Growth kinetic of BT-549-GFP + MSC spheroids represented in spheroid diameter over 13 days. The representative phase-contrast microscopy images of spheroids formation over the course of seven days are reported in Supplementary Fig. 8A. Data are presented as the mean ± SD (n = 3); (right) representative phase-contrast microscopy image of the spheroids grown at day 13. Magnification: 10 × , scale bar = 100 μm. B Representative confocal image of the heterotypic spheroid at day 13. BT-549-GFP cells are visualized in green and nuclei, stained with NucRed 647, in blue. White arrows in the merged images highlight the mixed composition of the spheroid (MSC, blue; BT-549-GFP, blue light). C Representative confocal images of BT-549-GFP/MSC spheroids grown at day 13 and then incubated with Ir_en-AuSiO₂_CL4, Ir_en-AuSiO₂_Gint4.T, Ir_en-AuSiO₂_CL4_Gint4.T, Ir_en-AuSiO₂_Scr or unconjugated Ir_en-AuSiO₂_ COOH/NHS for 24 h at 37 °C. Nanoparticles, BT-549-GFP cells and nuclei are displayed in red, green and blue, respectively. 3D images are shown. B,C Magnification: 10 × , 1.0 × digital zoom, scale bar = 100 μm. All digital images were captured under the same settings to enable a direct comparison of staining patterns