Richard King and Carmen Fernandez-Metzler Pages 541 - 545 ( 5 )
Advances in mass spectrometry continue to bring new and exciting capabilities to the study of drug metabo-lism. This review covers the hybrid linear ion trap – triple quadrupole mass spectrometer, the QTrap. While still a recentaddition to the arsenal of mass spectrometry techniques available to the metabolism scientist, reports in the literaturehighlight the advantages of the system for metabolite identification. The system combines the selective scans of the triplequadrupole with the high speed, high sensitivity of the ion trap allowing metabolites to be found and characterized in asingle scan. Additionally, the system has MS3 and time delayed fragmentation scans that aid in structure elucidation.Since the fragmentation occurs in the collision cell of the triple quadrupole, the traditionally rich fragmentation of the col-lision cell fragmentation is preserved. In addition to helping to make traditional processes more efficient, work has been done that shows the potential of the in-strument to change traditional DMPK approaches. Researchers have reported methods that allow for both qualitativeanalysis of circulating metabolites and quantification of parent drug within the same analysis. The approaches reportedshow how the instrument can be used to collect more information from every sample and potentially streamline typicaldrug metabolism assays.
Q-Trap MS, LC-MS/MS, metabolite identification, hybrid linear ion trap, MS3, DMPK assays
Department of Drug Metabo-lism, Merck and Co., Inc., West Point, PA 19486, USA.