MALDI-MS法中多电荷单体和单电荷多聚体分子离子形成机理的研究之二──负离子质谱的研究  

A Study of the Factors Influencing the Formation of Singly Charged Oligomers and Multiply Charged Monomers by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry(Ⅱ)—Negative Charged Ions

作　　者：赵善楷[1] 朱智华[1] 钟峰 查庆民 

机构地区：[1]中山大学测试中心,广州510275

出　　处：《质谱学报》1998年第1期1-5,共5页Journal of Chinese Mass Spectrometry Society

基　　金：国家自然科学基金

摘　　要：本文通过观察不同样品浓度、不同基体、不同基底所形成MALDI—MS负离子谱图中多电荷单体及单电荷多聚体的情况，了解其形成的规律。实验结果发现随着样品浓度增加，谱图中单电荷多聚体增加；不导电的硝化纤维膜基底比导电良好的银片基底谱图中多电荷离子增加。以上两种现象与正离子谱基本相似。对比α—氰基—4—羟基肉桂酸和阿魏酸两种基体的负离子谱图，发现与正离子谱图相同，在α—氰基—4—羟基肉桂酸谱图中多电荷离子明显多于阿魏酸。对上述实验结果分别就其形成机理作了讨论。By the observation of negative MALDl mass spectra obtained with different concentration of sample solution; different matrices and different substrates, the factors iafluencing the formation of singly charged oligomers and multiply charged monomers are investigated. The results demonstrate that singly charged oligomers increased with the increase of sample concentration; more multply charged monomers appeared with the use of nitrocellulose mernbrane as substrate than that with silver plate. The above results are simila to that observed in positive ion MALDI mass spectra. By the comparison of MADLI mass spectra obtained with the use of Q-cyano,4-hydroxycinnandc acid(4HHCA) and sinapinic acid(SA)as matrix, more multiply charged monomers are found with 4HCCA as matrix. That is also the seem as in positive ion spectra. The mechanism of the formation of negative ion spectra mentioned above are discussed.

关 键 词：MALDI MS 员离子质谱 质谱 谱图 

分 类 号：O657.6[理学—分析化学]