一系列阳离子性卟啉化合物的基质辅助激光解吸质谱行为

应用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)研究了一系列阳离子性卟啉化合物的质谱行为.结果表明,阳离子性卟啉与非离子性卟啉化合物的激光解吸电离方式有明显不同.对于四-氮R基(R=甲基,乙基,丙基,苄基)吡啶基卟啉,吡啶基氮上的侧链基团(R)可明显影响该类化合物在MALDI-TOF-MS测试过程中离子形成方式;R基团的增大以及平衡阴离子半径的增大可增加平衡阴离子与卟啉环阳离子之间相互作用力的共价成分,因此在MALDI-TOF-MS测定过程中能够得到卟啉环阳离子与多个平衡阴离子结合在一起的较高质量数的离子峰.另外,还初步探讨了阳离子性卟啉化合物的激光解吸电离机理.

Application of Matrix-assisted Laser Desorption/Ionization-time of Flight-mass Spectrometry in Characterizing a Series of Cationic Porphyrins

The matrix assisted laser desorption/ionization time of flight mass spectrometric behavior of a series of cationic porphyrins was studied. The results showed the desorption/ionization ways of cationic porphyrins were different from those of non ionic porphyrins. The space volume of the side chain groups of the porphyrins apparently affects the desorption/ionization mechanism of the formation of ions. The larger the space volume of the side chain groups and anions is, the larger the portion of the covalence is between the porphyrin cycle cation and the balance anions. As a result, the higher mass ion peaks formed by the porphyrin cycle cation combined with more anions appeared in the MALDI TOF mass spectra. The desorption/ionization mechanisms of the cationic porphyrins were also discussed in this paper.