Chen Tsung-Chi, Webb Ian K, Prost Spencer A, Harrer Marques B, Norheim Randolph V, Tang Keqi, Ibrahim Yehia M, Smith Richard D
Biological Sciences Division, Pacific Northwest National Laboratory , Richland, Washington 99352, United States.
Anal Chem. 2015 Jan 6;87(1):716-22. doi: 10.1021/ac503564c. Epub 2014 Dec 8.
Structures for lossless ion manipulations (SLIM) have recently demonstrated the ability for near lossless ion focusing, transfer, and trapping in subatmospheric pressure regions. While lossless ion manipulations are advantageously applied to the applications of ion mobility separations and gas phase reactions, ion introduction through ring electrode ion funnels or more conventional ion optics to SLIM can involve discontinuities in electric fields or other perturbations that result in ion losses. In this work, we developed and investigated a new funnel design that aims to seamlessly couple to SLIM at the funnel exit. This rectangular ion funnel (RIF) was initially evaluated by ion simulations, fabricated utilizing printed circuit board technology, and tested experimentally. The RIF was integrated to a SLIM-time of flight (TOF) MS system, and the operating parameters, including RF, DC bias of the RIF electrodes, and electric fields for effectively interfacing with a SLIM, were characterized. The RIF provided a 2-fold sensitivity increase without significant discrimination over a wide m/z range and well matched to that of SLIM, along with greatly improved SLIM operational stability.
用于无损离子操控的结构（SLIM）最近已证明能够在低于大气压的区域实现近乎无损的离子聚焦、转移和捕获。虽然无损离子操控有利地应用于离子迁移率分离和气相反应的应用，但通过环形电极离子漏斗或更传统的离子光学器件将离子引入到SLIM中可能会涉及电场的不连续性或其他导致离子损失的扰动。在这项工作中，我们开发并研究了一种新的漏斗设计，旨在在漏斗出口处与SLIM无缝耦合。这种矩形离子漏斗（RIF）最初通过离子模拟进行评估，利用印刷电路板技术制造，并进行了实验测试。RIF被集成到一个SLIM-飞行时间（TOF）质谱系统中，对包括RIF电极的射频、直流偏置以及与SLIM有效接口所需的电场等操作参数进行了表征。RIF在很宽的m/z范围内提供了两倍的灵敏度提升，且无明显歧视，与SLIM的灵敏度良好匹配，同时大大提高了SLIM的操作稳定性。
