FIGURE 1.

Distribution of ²H-α-tocopherol isotopomers. Single-ion recording mass spectrometer data were used to obtain the isotopic distribution of ²H-α-tocopherol isotopomers extracted from collard greens similarly to what was described for ²H-phylloquinone (14, 21). The predominant isotopomers in the collard green α-tocopherols were m/z 438–442 as indicated by the box; these ions encompassed ∼60% of the total α-tocopherol ion abundance. No unlabeled α-tocopherol (m/z 429) was detected. The ions at m/z 438–442 [equivalent to 9–13 deuterium (²H) atoms, respectively, on the α-tocopherol) were chosen for selected ion recording in plasma extracts.