Vital imaging of sanguinarine uptake and distribution in MCF-7 cells by laser-scanning confocal microscopy. 5 μg/ml Hoechst and 10 μM sanguinarine were simultaneously added to living cultures and images taken with both blue (Hoechst) and red (sanguinarine) channels every 2 minutes for two hours. (a-c) Three frames from a time lapse movie (a, b and c = 6, 60, and 120 minutes after drug addition, respectively), showing Hoechst fluorescence. Using the Nikon C1 software, the average pixel intensities of circles encompassing approximately the central third of each of 10 nuclei were charted over time (d). Over this timecourse, Hoechst nuclear fluorescence progressively increases. (e-g) Three frames from the same time-lapse movie and same timepoints shown in (a-c), demonstrating that sanguinarine uptake and disposition differs from that of Hoechst. Nuclei are more rapidly labeled by sanginarine, but this signal is shorter-lived, and begins to noticeably diminish after a few hours (h).