Improved determination of uracil and dihydrouracil in plasma after a loading oral dose of uracil using high-performance liquid chromatography with photodiode array detection and porous graphitic carbon stationary phase

The developed method was fully validated and has significantly reduced running time when compared to previous assay using porous graphitic stationary phase, allowing complete resolution of uracil, dihydrouracil and internal standard. This assay might be suitable to investigate the eventual correlation between concentrations of uracil and dihydrouracil in plasma after an oral loading dose and DPD enzyme activity, with potential contribution to therapeutic drug monitoring.