A method has been developed to determine the levels of α-tocopherol in human plasma
and colon tissue using gas chromatography with mass spectrometric detection. The
samples were acquired from 27 patients with Crohn’s disease. Samples were
deproteinized and α-tocopherol was obtained using a two-step extraction and
measured by GC-MS without prior derivatization. The analytical parameters of the
method were satisfactory: the intra-day and inter-day coefficients of variation were
below 7% and quantitative recoveries range between 92.2-100.5%. The method shows
an excellent linear range from 0.6-64.3 μmol/L. The median measured α-tocopherol
concentration in human plasma was 21.6 μmol/L and in healthy colon tissue and tissue
affected by Crohn’s disease was 26.5 nmol/mg and 34.9 nmol/mg, respectively. We did
not find any statistically significant correlation or differences between the α-tocopherol
content in plasma and tissue. Overall, our method has potential to be easily implemented
in special studies for monitoring α-tocopherol as a biomarker of oxidative stress.
