Individual acidic organelle pH measurements by capillary electrophoresis.

摘要: This report describes the pH measurement of individual acidic organelles isolated from human leukemia CCRF-CEM and CEM/C2 cells. These cells were allowed to endocytose fluorescein tetramethylrhodamine dextran (FRD), a ratiometric probe that has as pH-dependent fluorophore pH-independent fluorophore. Isolated organelle fractions these then subjected capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) analysis. The at two different wavelengths, selected on basis emission range FRD probe, gives intensity ratio used calculate calibration curve. curve was constructed CE-LIF measurements liposomes loaded several buffer standards. respective median values are 5.1 +/- 0.2 in 6.1 0.4 compare well pixel-based epifluorescence microscopy whole where corresponding average 5.0 0.6 (n = 15) 6.2 0.7 15). A comparison between cell types suggests lower may be relevant protonation sequestration weak base anticancer drugs such doxorubicin. determination vesicles, liposomes, is new resource for measuring investigating role acid-base properties subcellular-size compartments.