Factors affecting the ultraviolet laser desorption of proteins.
Factors affecting the ultraviolet laser desorption of proteins.
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DOI：
10.1002/rcm.1290030708
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发表时间：
1989-07-01
期刊：
影响因子：
--
通讯作者：
Chait, B T
中科院分区：
文献类型：
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作者：
Beavis, R C;Chait, B T
描述了用基质辅助紫外激光解吸法从蛋白质中制备高质量准分子离子。一个简单的飞行时间系统，使用Q开关的四倍频Nd-YAG激光解吸蛋白质分子的质量范围高达116,000 u的观察完整的，单电荷准分子离子从700 fmol的β-半乳糖苷酶亚基（mol.wt = 116,336 Da）。显示了蛋白质的正离子和负离子光谱。介绍了四种性能与烟酸相当或更好的新型基质材料。约500（半高全宽定义）的质量分辨率被证明为蛋白质与摩尔重量小于20,000 Da。产品种类，在基质中的快速光化学反应形成的，观察到形成加合物离子与蛋白质分子。这些加合物离子是观察到的蛋白质准分子离子峰的宽度的重要原因。本文讨论了激光解吸探测大质量准分子离子时的实际物理问题，如探测器过载等。
The production of high-mass quasimolecular ions from proteins by matrix-assisted ultraviolet laser desorption is described. A simple time-of-flight system using a Q-switched frequency-quadrupled Nd-YAG laser to desorb protein molecules is shown to have a mass range of up to 116,000 u by the observation of intact, singly charged quasimolecular ions from 700 fmol of beta-galactosidase subunit (mol.wt = 116,336 Da). Both positive- and negative-ion spectra of proteins are shown. Four new matrix materials, with properties as good as or better than nicotinic acid, are described. A mass resolution of approximately 500 (full width at half maximum definition) is demonstrated for proteins with mol.wt less than 20,000 Da. Product species, formed by fast photochemical reactions in the matrix, are observed to form adduct ions with protein molecules. These adduct ions are a significant cause of the observed broadness of protein quasimolecular ion peaks. The practical physical considerations in detection of large-mass quasimolecular ions from laser desorption, such as detector overloading, are discussed.