Reactive Metabolite Screening

• GSH, KCN, semicarbazide trapping
• UPLC with Q-TOF-MS or QE-Orbitrap-MS and UV detection

One of the reasons behind unexpected drug induced toxicity can be chemically reactive metabolites that bind covalently to protein or DNA. Due to their high reactivity and short life-span, these metabolites cannot be analyzed directly as such, but have to be first stabilized by trapping agents, such as S-glutathione (GSH), cyanide (KCN) or semicarbazide (SCA). Of these, GSH is clearly the most used trapping agent, although KCN and SCA may be used for trapping certain types of reactive metabolites that are not trapped by GSH, such as iminium ions or aldehydes. As in any analysis of unknown drug metabolites, the use of liquid chromatography with high-resolution mass spectrometry delivers the highest quality data with the shortest time consumption also in our reactive metabolite screening assay.