KVI Atomic and Molecular Physics, University of Groningen, Zernikelaan 25, NL-9747 AA Groningen, The Netherlands.
Phys Chem Chem Phys. 2010 Apr 14;12(14):3376-83. doi: 10.1039/b924145k.
We have studied multiple ionization and dissociation of a trapped protonated peptide (leucine enkephalin) as induced by keV singly and doubly charged ions (H(+), He(+, 2+)) to demonstrate the potential of keV ions as a future tool for peptide identification. In contrast to conventional excitation techniques, the fragmentation pattern exhibits very strong peaks due to loss of sidechains in addition to those due to backbone scission. The results can be understood on the basis of the energy deposited into the peptide via electronic stopping. A pronounced dependence of the fragmentation pattern on the electronic structure of the projectile ions can be attributed to different electron capture efficiencies from localized molecular orbitals.
我们研究了被捕获的质子化肽（亮氨酸脑啡肽）在 keV 单电荷和双电荷离子（H(+)、He(+、2+)）诱导下的多次电离和离解，以证明 keV 离子作为未来肽鉴定工具的潜力。与传统的激发技术相比，除了由于主链断裂产生的峰外，由于侧链丢失，碎片模式还显示出很强的峰。这些结果可以基于通过电子阻止沉积在肽中的能量来理解。由于从局域分子轨道中具有不同的电子俘获效率，碎片模式对射弹离子的电子结构的依赖性非常明显。
