desorption/ionization (MALDI). The fragmentation efficiency as measured by post-source decay in a reflectron time-of-flight mass spectrometer increases by a factor of 2-3.5. Peptide bonds adjacent to modified residues are more susceptible to cleavage than in the non-derivatized peptide ions. The increased lability of these bonds gives rise to more complete sequence information. In addition, the relative
用
乙酰丙酮(
戊烷-2,4-二酮)修饰
缓激肽,[1-5]-
缓激肽,脾瘦素和两个合成五肽中的精
氨酸残基,可显着增加基质辅助激光解吸/产生的序列特异性片段离子的相对丰度电离(MALDI)。在反射式飞行时间质谱仪中通过源后衰减测量的碎裂效率提高了2-3.5倍。与未衍生肽离子相比,与修饰残基相邻的肽键更易于裂解。这些键的不稳定性增加导致更完整的序列信息。另外,增强了序列特异性片段离子的相对丰度。