As a step towards development of a high-resolution ion mobility mass spectrometer using the orbitrap mass analyzer platform, we describe herein a novel reverse-entry ion source (REIS) coupled to the higher-energy C-trap dissociation (HCD) cell of an orbitrap mass spectrometer with extended mass range. Development of the REIS is a first step in the development of a drift tube ion mobility-orbitrap MS. The REIS approach retains the functionality of the commercial instrument ion source which permits the uninterrupted use of the instrument during development as well as performance comparisons between the two ion sources. Ubiquitin (8.5 kDa) and lipid binding to the ammonia transport channel (AmtB, 126 kDa) protein complex were used as model soluble and membrane proteins, respectively, to evaluate the performance of the REIS instrument. Mass resolution obtained with the REIS is comparable to that obtained using the commercial ion source. The charge state distributions for ubiquitin and AmtB obtained on the REIS are in agreement with previous studies which suggests that the REIS-orbitrap EMR retains native structure in the gas phase. Graphical Abstract ᅟ.

中文翻译：

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反向进入离子源Orbitrap质谱仪的开发和评估。

作为开发使用orbitrap质谱仪平台的高分辨率离子迁移质谱仪的一步，我们在此介绍了一种新型的反向进入离子源（REIS），该离子源耦合到高能C阱解离（HCD）池中。质量范围扩大的Orbitrap质谱仪。REIS的开发是开发漂移管离子迁移率轨道质谱仪的第一步。REIS方法保留了商用仪器离子源的功能，该功能允许在开发过程中不间断地使用仪器以及在两个离子源之间进行性能比较。泛素（8.5 kDa）和与氨转运通道结合的脂质（AmtB，126 kDa）蛋白复合物分别用作模型可溶性蛋白和膜蛋白，以评估REIS仪器的性能。使用REIS获得的质量分辨率与使用商业离子源获得的质量分辨率相当。在REIS上获得的泛素和AmtB的电荷状态分布与以前的研究一致，这表明REIS-orbitrap EMR在气相中保留了天然结构。图形摘要ᅟ。