Figure 2.

HPLC analysis of CoQ₁₀in samples.A, outline of cell sample preparation with (normal fixation) or without (rapid fixation) an intermediate step in which cells are scraped in PBS. B, calibration curves for CoQ₉ and CoQ₁₀ standards. C, HT29 cell samples exhibit two peaks assigned as CoQ₁₀H₂ and CoQ₁₀ (black); oxidation with p-benzoquinone (p-BQ) leads to the disappearance of the CoQ₁₀H₂ and an increase in the intensity of CoQ₁₀ peak (red). Spiking with authentic samples of CoQ₁₀ (dark blue) or CoQ₁₀H₂ (light blue), confirmed the assignment of the corresponding peaks in the cell sample. The data are representative of at least three independent runs.