Infrared multiphoton dissociation in an external ion reservoir
Infrared multiphoton dissociation in an external ion reservoir
复制标题
DOI：
10.1021/ac990176n
复制
发表时间：
1999-06-01
影响因子：
7.4
通讯作者：
Griffey, RH
中科院分区：
文献类型：
--
作者：
Hofstadler, SA;Sannes-Lowery, KA;Griffey, RH
在这项工作中，我们提出了一种新颖的方案，用于在质量分析器外部的外部离子库中执行红外多光子解离（IRMPD），该外部离子库由纯射频多极杆和一对静电透镜元件组成。电喷雾电离 (ESI) 产生的离子积聚在纯射频六极杆中，并通过质谱仪源区域中 CW CO2 激光器的 10.6 μm 照射而解离。该方案与其他 IRMPD 方案不同，因为解离发生在光谱仪的空间不同区域，并且独立于用于分析碎片离子的质谱平台。该技术的有效性通过 20 聚体硫代磷酸酯寡核苷酸的 ESI IRMPD FTICR 质谱法得到了证明。将外部 IRMPD 方案与喷嘴分离器解离和传统的内置 IMPD 进行比较，结果表明信噪比和碎片产率显着提高，特别是对于较大、带电较高的碎片离子。
In this work we present a novel scheme for performing infrared multiphoton dissociation (IRMPD) external to the mass analyzer in an external ion reservoir consisting of an rf-only multipole and a pair of electrostatic lens elements. Ions generated by electrospray ionization (ESI) are accumulated in an rf-only hexapole and dissociated by irradiation at 10.6 mu m from a CW CO2 laser in the source region of the mass spectrometer. This scheme is unique from other IRMPD schemes as dissociation occurs in a spatially distinct region of the spectrometer and is independent of the mass spectrometry platform used to analyze the fragment ions. The effectiveness of the technique is demonstrated with ESI IRMPD FTICR mass spectrometry of a 20-mer phosphorothioate oligonucleotide. A comparison of the external IRMPD scheme with nozzle-skimmer dissociation and conventional in-cell IRMPD reveals a significant improvement in signal-to-noise ratio and fragment yield, particularly for larger, more highly charged fragment ions.