Production and analysis of multiply charged negative ions by liquid atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry.
Production and analysis of multiply charged negative ions by liquid atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry.
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DOI：
10.1002/rcm.8246
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发表时间：
2021-01
期刊：
影响因子：
--
通讯作者：
Cramer R
中科院分区：
文献类型：
--
作者：
Hale OJ;Ryumin P;Brown JM;Morris M;Cramer R
液体大气压基质辅助激光解吸/电离(AP-MALDI)已被证明能够产生类似于电喷雾电离(ESI)的多电荷分析物离子，且样品消耗少，离子产率持久、稳定，可用于质谱(MS)的灵敏分析。此前的报道主要集中在正离子生产方面。在这里，我们报告了液体AP-MALDI产生类ESI负离子的初步优化，并将其应用于多肽/蛋白质、DNA和脂质的分析。本研究使用的仪器与早期的液体AP-MALDI MS研究相同，该研究使用一个简单的非商业AP离子源，该离子源连接到Waters Synapt G2-Si质谱仪，并结合了一个加热的离子转移管。液体MALDI矩阵的制备类似于正离子模式分析，但已针对负离子模式进行了调整，将发色团更改为3-氨基喹啉和9-氨基吖啶以进行进一步改进。对于DNA，液体AP-MALDI MS分析得益于切换到基于9-氨基吖啶的MALDI样品和负离子模式，与正离子模式相比，电荷数量增加了2倍，分析物离子信号强度增加了10倍以上。ATGCAT的检出限约为10 fmoL。对于脂类，负离子模式分析提供了一组完全正交的检测到的脂类。在液体AP-MALDI MS分析中，负离子模式是取代正离子模式的灵敏选择。特别是，脂类和DNA的分析得益于所检测的脂类的互补性和负离子模式下极大的DNA离子信号强度。
Liquid atmospheric pressure matrix‐assisted laser desorption/ionisation (AP‐MALDI) has been shown to enable the production of electrospray ionisation (ESI)‐like multiply charged analyte ions with little sample consumption and long‐lasting, robust ion yield for sensitive analysis by mass spectrometry (MS). Previous reports have focused on positive ion production. Here, we report an initial optimisation of liquid AP‐MALDI for ESI‐like negative ion production and its application to the analysis of peptides/proteins, DNA and lipids. The instrumentation employed for this study is identical to that of earlier liquid AP‐MALDI MS studies for positive analyte ion production with a simple non‐commercial AP ion source that is attached to a Waters Synapt G2‐Si mass spectrometer and incorporates a heated ion transfer tube. The preparation of liquid MALDI matrices is similar to positive ion mode analysis but has been adjusted for negative ion mode by changing the chromophore to 3‐aminoquinoline and 9‐aminoacridine for further improvements. For DNA, liquid AP‐MALDI MS analysis benefited from switching to 9‐aminoacridine‐based MALDI samples and the negative ion mode, increasing the number of charges by up to a factor of 2 and the analyte ion signal intensities by more than 10‐fold compared with the positive ion mode. The limit of detection was recorded at around 10 fmol for ATGCAT. For lipids, negative ion mode analysis provided a fully orthogonal set of detected lipids. Negative ion mode is a sensitive alternative to positive ion mode in liquid AP‐MALDI MS analysis. In particular, the analysis of lipids and DNA benefited from the complementarity of the detected lipid species and the vastly greater DNA ion signal intensities in negative ion mode.
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影响因子：
16.6
作者：
Cramer, Rainer;Pirkl, Alexander;Hillenkamp, Franz;Dreisewerd, Klaus
通讯作者：
Dreisewerd, Klaus
影响因子：
3.4
作者：
Cramer, R;Corless, S
通讯作者：
Corless, S
影响因子：
4.4
作者：
Towers, Mark W.;Mckendrick, John E.;Cramer, Rainer
通讯作者：
Cramer, Rainer
DOI：
10.1007/s13361-012-0414-y
发表时间：
2012-10-01
影响因子：
3.2
作者：
Trimpin, Sarah;Wang, Beixi;McEwen, Charles N.
通讯作者：
McEwen, Charles N.
影响因子：
1.8
作者：
Breuker, K;Knochenmuss, R;Zenobi, R
通讯作者：
Zenobi, R