Charge transfer dissociation (CTD): a new activation method in Evry for probing the structure of natural or synthetic compounds

The combination of soft ionization methods with tandem mass spectrometry (MS/MS or MSn) has become an essential tool for the fine structural analysis of biomolecules. The most popular MS/MS method is based on collision-induced dissociation (CID) of the gas-phase analyte. However, this method suffers several limitations, such as incomplete fragmentation or the loss of labile chemical functional groups, leading to a loss of structural information.To reach a more complete characterization, especially for biomolecules with high isomerism, new activation methods have been developed for several years, including Charge Transfer Dissociation (CTD). We have implemented the CTD fragmentation method in 2022 on an ion trap of the LAMBE mass spectrometry platform.Charge Transfer Dissociation has been recently introduced. [1] CTD is based on the collision between strongly accelerated (keV) He+ ions and a precursor ion. This method allows a charge exchange process, leading to the formation of radical ions, whose fragmentation appear complementary to CID processes. Several examples of application will be presented. References1.D. W. Hoffmann, G. P. Jackson J. Am. Soc. Mass Spectrom. 25, 1939-1943 (2014).