Confocal microscopy analysis and co-localization studies.

<p>A, accumulation of bioconjugates in HT-29, MKN-45 and KYSE-30. Cells were incubated with BODIPY-labeled ONCOFID-P (50 µg/mL in paclitaxel equivalents) or ONCOFID-S (50 µg/mL in SN-38 equivalents) for 1 hour, washed and fixed before analysis. B, co-localization analysis of bioconjugates in lysosomes. HT-29, MKN-45 and OE-33 cells were treated with LysoTracker green, incubated with BODIPY-labeled compounds and finally analyzed by confocal microscopy. Left pictures show the fluorescence of the labeled bioconjugates (red) in single cells, while central pictures illustrate signals (green) from lysosomes. The merging of the 2 components is visible in right pictures. Lysosomes were occupied by bioconjugates by ∼90% to 100%, as assessed by the Zeiss’profile software tool. Experiments were repeated at least twice with consistent results.