The number of metabolites identified with the precursor ion scan method was compared to the number of metabolites identified with an enhanced MS method. Table 1 illustrates that the precursor ion scan method clearly identifies and confirms more metabolites in all cases.
For identification of Phase II metabolites, an IDA method with a neutral loss scan of 176 as the survey scan was used to selectively identify three glucuronide species of buspirone (Figure 5). Prior MS/MS experiments with buspirone glucuronides indicated the aglycon species as the major fragment ion, and subsequently, the IDA method was set to include an MS3 experiment following EPI, in order to gain more structural information. The MS3 experiment run on the aglycon metabolite (m/z 402) is much richer in structural information due to the triple quadrupole fragmentation pattern of the Q TRAP system. Figure 5 shows the resulting MS3 spectra of m/z 402 from the EPI scan, which, combined with supporting chemical structural information, clearly indicates the site of hydroxylation. This powerful automated approach to identifying and characterizing metabolites all in a single LC/MS IDA analysis can be used on expected and unexpected metabolites.
The Q TRAP LC/MS/MS system with IDA and Metabolite ID automates every aspect of metabolite identification and provides the highest quality results. Advanced, automated data processing and reporting puts highconfidence results at your fingertips in less time. The Q TRAP LC/MS/MS system, a hybrid linear ion trap, provides superior ion trap performance and high-performance triple quadrupole functionality. Scan functions unique to ion trap MS, such as precursor ion and neutral loss scans, simplify the task of finding