物理化学学报 >> 1997, Vol. 13 >> Issue (03): 252-257.doi: 10.3866/PKU.WHXB19970313

研究论文 上一篇    下一篇

两种氨基酸中[MH-CO2H2]+的特征质谱碎裂

佘益民,熊晓虹,周雨,刘淑莹   

  1. 中国科学院长春应用化学研究所,长春 130022|湖南科技信息研究所,长沙 410001
  • 收稿日期:1996-09-16 修回日期:1996-12-03 发布日期:1997-03-15
  • 通讯作者: 刘淑莹

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

摘要:

运用低能碰撞诱导解离(CID)研究了电子轰击(EI)、快原子轰击(FAB)电离条件下质子化亮氨酸与异亮氨酸解离产生亚稳离子[MH-CO2H2]+的单分子质谱碎裂,二种异构体呈现出了各自不同的解离特征. 根据CID的特征碎片离子和氘代同位素标记实验,提出了其碎裂过程存在离子/中性(碎片)复合物中间体碎裂机理,并对有关的特征离子的形成进行了讨论.

关键词: 碰撞诱导解离, 离子/中性(碎片)复合物, 亮氨酸, 异亮氨酸

Abstract:

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