A sensitive gas chromatographic-mass spectrometric method is described for reliably measuring endogenous uracil in 100 μl of human plasma. Validation of this assay over a wide concentration range, 0.025 ♂m to 250 ♂m (0.0028 μg/ml to 28 μg/ml), allowed for the determination of plasma uracil in patients treated with agents such as eniluracil, an inhibitor of the pyrimidine catabolic enzyme, dihydropyrimidine dehydrogenase. Calibration standards were prepared in human plasma using the stable isotope, [15N2]uracil, to avoid interference from endogenous uracil and 10 ♂m 5- chlorouracil was added as the internal standard.
|Original language||English (US)|
|Number of pages||10|
|Journal||Journal of Chromatography B: Biomedical Sciences and Applications|
|Publication status||Published - Feb 11 2000|
- Dihydropyrimidine dehydrogenase
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