Acta Phys. -Chim. Sin. ›› 1997, Vol. 13 ›› Issue (03): 252-257.doi: 10.3866/PKU.WHXB19970313

• ARTICLE • Previous Articles     Next Articles

Characteristic Fragmentations of [MH-CO2H2]+ in Two Kinds of Amino Acid

She Yi-Min,Xiong Xiao-Hong,Zhou Li;Liu Shu-Ying   

  1. Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022|Hunan Institute of Scientific Technological Information,Changcha 410001
  • Received:1996-09-16 Revised:1996-12-03 Published:1997-03-15
  • Contact: Liu Shu-Ying


Unimolecular fragmentations of metastable ions [MH-CO2H2]+ in leucine (Leu) and isoleucine (Ile) were studied by electron impact (EI) ionization and fast atom bombardment (FAB) ionization. The different characteristic fragment ions resulted from the collision-induced dissociation (CID) spectra of [MH-CO2H2]+ ions in isomeric amino acids were observed. Deuterium labelling experiment was used to demonstrate the behaviour of the dissociation of [MH-CO2H2]+ion, and the possible fragment mechanisms involving intermediary ion/neutral complexes or proton-bound complexes were proposed and discussed.

Key words: Collision-induced dissociation, Ion/neutral complex, Leucine, Isoleucine