Multigenerational Collision-Induced Dissociation for Characterization of Organic Compounds

There are many cases in which limited information is obtained from a single stage of tandem mass spectrometry (MS2 or MS/MS). For example, isomeric cathinones give similar product ion MS2 spectra, but they can be differentiated by their unique MS3 fragments. Other drugs such as oxycodone and noroxycodone lose water in a single-stage tandem mass spectrometry experiment but give rich structural information in subsequent stages, as do many peptides. Here we utilize multigenerational collision-induced dissociation (CID) on a miniature mass spectrometer and emphasize useful applications. Unique fragmentation patterns consisting of several generations of fragment ions are obtained in these multigenerational spectra, allowing discrimination of cathinone isomers and structural characterization of small molecules, including drugs and peptides, all using a single sequence of ion injection, isolation, and mass scanning.