Ion-Induced Dipole Interactions and Fragmentation Times : Cα -Cβ Chromophore Bond Dissociation Channel

International audienceThe fragmentation times corresponding to the loss of the chromophore (Cα− Cβ bond dissociation channel) after photoexcitation at 263 nm have been investigated for several small peptides containing tryptophan or tyrosine. For tryptophan-containing peptides, the aromatic chromophore is lost as an ionic fragment (m/z 130), and the fragmentation time increases with the mass of the neutral fragment. In contrast, for tyrosine-containing peptides the aromatic chromophore is always lost as a neutral fragment (mass = 107 amu) and the fragmentation time is found to be fast (