Gas-phase ion chemistry of protonated melatonin
David Bongiorno1, Leopoldo Ceraulo, Lorenzo Camarda
1Dipartimento di Chimica e Tecnologie Farmaceutiche, Università di Palermo, Via Archirafi 32, I-90123 Palermo, Italy.
Abstract:
The gas-phase ion chemistry of protonated melatonin has been investigated by mass spectrometric (MS) techniques involving chemical ionisation, fast atom bombardment and electrospray ionisation. Either naturally- occurring or collision-induced decomposition e-D derivatives obtained by exchange with D(2)O. The analysis of experimental results allows definite pathways for the formation of the ion at m/z 174 to be assigned and sheds some more light on the overall fragmentation pathways. Experiments on labelled derivatives evidenced H-D scrambling processes during fragmentation.
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