Redox reactions are integral parts of many cellular processes. Thus, they are extensively studied in vitro and in vivo. Electrochemistry (EC) represents a pure instrumental approach to characterize direct and indirect effects of redox reactions on bioorganic molecules.
5-Fluorouracil (5-FU) is a low-molecular-weight anticancer drug in clinical use for several solid tumors in humans. Currently, the most widely used methodology for 5-FU quantitation is liquid chromatography–tandem mass spectrometry (LC–MS-MS) with either liquid–liquid extraction (LLE), protein precipitation, or a combination of both as sample cleanup procedures.
Gas chromatography with electron ionization and mass spectrometry (GC–EI-MS) detection is a workhorse among analytical techniques in metabolomics. A major challenge in the utilization of GC–EI-MS in metabolomics is the identification of unknowns.