Fig. 2: Me₂NNMe₂ accumulation in the ER-derived vesicles.

a Representative fluorescence microscopy images and overlaid differential interference contrast images of the ER lumen of ER-YFP-transfected SW480 cells treated with 10 µM Me₂NNMe₂ for 24 h (scale bar: 50 µm). b Life-cell fluorescence imaging of ER-located YFP-transfected SW480 cells treated with 1 µM Me₂NNMe₂. Time after treatment is indicated as hh:mm (scale bar: 10 µm). c Representative fluorescence microscopy images of mitochondria (MitoTracker) showing no overlap with vesicles in ER-YFP-transfected SW480 cells treated with 10 µM Me₂NNMe₂. (scale bar: 50 µm). d Raman microspectroscopy of SW480 cells treated with 10 µM Me₂NNMe₂ for 24 h. Principal component analysis (PCA) of Raman spectra can differentiate between background (black), cell (green) and vesicles (red). CLS fitting of Me₂NNMe₂ Raman spectrum to the spectral map of the cell revealed accumulation of the drug inside the vesicles