a) Dox fluorescence images of adherent NDL cells in culture and isolated nuclei. Cells were treated with released CuDox, free Dox, or liposomal CuDox (CuDox-LTSL) and images were acquired 15 min, 5 h or 24 h after incubation at 37°C. b-c) NDL cellular fluorescence intensity in arbitrary units (AU) after 24 h incubation in media (NT Control) or treatments as above, and as quantified by (b) Image J or (c) flow cytometry. d) Nuclear Dox fluorescence across various treatments at 5 h via image-based fluorescence measurements of intact cells. e) Dox accumulation in whole cell lysate, isolated cytoplasm and isolated nuclei from cells treated with free Dox or released CuDox at 24 h. Dox quantification was performed in the presence of Triton X-100 and HCl-isopropanol. Statistical analyses were performed using one-way ANOVA followed by a Tukey Post Hoc test. ***p < 0.001, n.s. = not significant.