Intracellular MGd uptake and ROS production. Fluorescence analysis was performed on live gated cells after 24 hours of incubation with 50 μM MGd and 50μM ascorbate in the (A) chemotherapy-sensitive cell line, 8226-RPMI, and the (B) highly chemotherapy-resistant line, DOX-10V. Histograms depict fluorescence uptake in live cells, with fluorescence on the x-axis and live cell counts on the y-axis. A shift to the right indicates increased MGd fluorescence. Con indicates mannitol control. Histograms shown are representative of triplicate measurements. Intracellular uptake of MGd and intracellular ROS production in C2E3 cells was also assessed by fluorescence microscopy after 24 hours incubation with 50 μM MGd and 50 μM ascorbate: (C) myeloma cells in gray scale transmission, (D) intracellular MGd uptake with MGd delineated by red fluorescence label, (E) ROS production as delineated by green fluorescence, which results from oxidation of DCFA to DCF, (F) MGd and ROS production in the same cells as represented by the overlay of red and green fluorescence resulting in the yellow color.