Focusing Differential Mobility Analyzer

描述（由申请人提供）：离子迁移谱仪与电喷雾离子源耦合并与质谱仪接口，是研究分子构象、分离质量异构体、分析复杂混合物和抑制化学背景的强大工具。限制该技术能力的原因之一是其相对较低的分辨率。气相扩散导致峰展宽，将分辨率限制在50-100级。本文提出了一种基于均匀静电场作用下离子聚焦和气体减速的气相离子分离替代原理。解析计算和数值模拟均表明，该方法可以达到几百的扩散极限分辨率。我们建议建立一种新型离子迁移率分析仪，称为聚焦差分迁移率分析仪（FDMA）。所提出的原型FDMA可以很容易地与商用质谱仪接口，并提供几百的理论分辨率和离子透射接近100%。本文的目的是论证在均匀电场和减速气流作用下，基于离子聚焦新原理的常压离子分离的可行性。将设计并制造一台FDMA样机。电喷雾离子源将与FDMA耦合。该设备将与安装在我们实验室的Thermo Finnigan公司的商用LCQ离子阱连接。该研究的成功将为科学界提供一种新型离子迁移率分析仪，该分析仪具有更好的分辨率和灵敏度，设计简单，与不同类型的质谱仪相结合。

DESCRIPTION (provided by applicant): Ion Mobility Spectrometer coupled with electrospray ion source and interfaced to a Mass Spectrometer is a powerful tool for the study of molecular conformations, separation of mass isomers, and analysis of complex mixtures and suppression of chemical background. One of the reasons that limit the capabilities of the technique is its relatively low resolving power. The gas-phase diffusion results in the peak broadening and limits the resolution at 50-100 level. We propose the alternative principle of gas-phase ion separation, based on ion focusing under the influence of uniform electrostatic field and decelerating gas flow. Both analytical calculations and numerical simulation show that a diffusion-limited resolution of several hundred can be achieved. We propose to build an ion mobility analyzer of the new type that is called Focusing Differential Mobility Analyzer (FDMA). The proposed prototype FDMA can be easily interfaced with commercial mass spectrometers and offers the theoretical resolution of several hundred and ion transmission close to 100%. The purpose of this proposal is the demonstration of the feasibility of atmospheric-pressure ion separation based on the new principle of ion focusing under the influence of uniform electrical field and decelerating gas flow. A prototype FDMA apparatus will be designed and built. The electrospray ion source will be coupled with FDMA. The devices will be interfaced with commercial LCQ ion trap of Thermo Finnigan, Inc., installed in our laboratory. The success of the research will provide a scientific community with a new class of ion mobility analyzer that combines better resolution and sensitivity with simplicity of design and interface to mass spectrometers of different types.