Figure 8. UV spectra of oxidized and reduced ubiquinone.

T67 cells were treated for 24 hours with 100 nM Qter or 10 µM native CoQ₁₀, then ubiquinone was immediately extracted, from an equal number of cells, with isopropyl alcohol (for further details see Materials and methods) and the UV spectra were recorded between 320 and 240 nm. The ubiquinone extracted from 100 nM Qter treated sample appears to be completely reduced with a maximum absorption peak at 290 nm, while the ubiquinone extracted from 10 µM native CoQ₁₀ treated sample has a maximum absorption peak shifted towards 275 nm, indicating the presence of the ubiquinone oxidized form. Spectra are representative of three different experiments.