Role of Ion Trap LC ‐ MS Techniques for the Identification of Drug Metabolites

Abstract

The theory and techniques of using ion trap mass spectrometry in identification of drug metabolites were discussed. Over decades of improvement, ion trap mass spectrometry has evolved as one of the matured techniques for identification of drug metabolites. With its significantly enhanced ion trapping capacity and efficiency, the linear ion trap makes possible many versatile designs of hybrid mass spectrometers. Consequently, many novel scan methods can be applied for metabolite identification purposes. In comparison with conventional triple-quadrupole mass spectrometers, ion traps have clear advantages in terms of detecting and elucidating unknown metabolites at very low levels. With the novel hybrid ion traps, the systematic information-dependent acquisition has become an integral part of modern drug discovery and development with its ability to speed up and streamline the metabolite identification process. The scan modes that are unique to these ion traps, such as enhanced product ion scan and MSn scan, have proven to be powerful tools for the purpose of structural elucidation of unknown chemical entities. When it is appropriately applied in the pharmaceutical research, the ion trap mass spectrometry can play a significant and unique role for the identification of unknown metabolites of drugs and drug candidates.