大黄酸ESI-IT MS质谱行为及碎片离子的量子化学研究

Study on Mass Behavior and Fragment Ions of Rhein by ESI-IT MS and Quantum Chemistry

中文关键词:大黄酸  电喷雾离子阱质谱  量子化学

Key Words:rhein  electrospray ionization ion trap mass spectrometry(ESI-IT-MS)  quantum chemistry

中文摘要:采用电喷雾-离子阱质谱(ESI-IT MS)，获取大黄酸分子的一级质谱和多级质谱碰撞诱导解离下的碎片离子，以量子化学计算大黄酸分子及其主要碎片离子的质谱行为。通过对质谱离子几何参数、键断裂能、电荷变化、自旋密度以及前线分子轨道的分析，可得到m/z 282.8、256.9、238.9、210.8、192.8、182.8、166.8离子的稳定构型以及质谱裂解途径，从而较系统地解释了大黄酸分子在ESI-IT MS中的裂解行为。

Abstract:The fragment ions of rhein in total ions mass chromatogram and collision inductive dissociation multi-level mass were studied by electrospray ionization ion trap mass spectrometry(ESI-IT MS).Quantum chemistry calculations were carried out to explore the mass behavior of rhein and the main fragment ions from the molecule.By analysing the characteristic of the fragment ions including geometry parameter,bond dissociation energy,changes of charge,spin density and frontier molecular orbital,the stable structures of the fragment ions with m/z 282.8,256.9,238.9,210.8,192.8,182.8,166.8,and fragmentation pathways could be obtained,the cracking behavior of rhein could be explained systematically by ESI-IT MS.