Figure 10.

Drug ondansetron and the three hydroxylated metabolites identified in Dear et al. 2010.²⁶² This study was a first demonstration of the use of quantum chemical-based theoretical calculations of CCS for small-molecule identification. The four isomers had indistinguishable MS/MS fragmentation spectra due to the hydroxyl moiety being located on the unfragmented benzene ring, thus, the matching of calculated CCS to the experimental CCS distributions was the sole distinguishing dimension of data for identification. Reproduced with permission from ref (262). Copyright 2010 Wiley and Sons, Ltd.