RUI: Development of Next-Generation Drift-Time Ion Mobility Spectrometry through the Application of Pulsed Ionization and Voltage Sweep Methodologies

在化学系化学测量和成像计划的支持下，惠特沃斯大学的Eric Davis和他的团队正在努力提高离子迁移率光谱(IMS)的能力，IMS是一种化学测量技术，通常用于安全和军事应用，用于检测爆炸物、毒品和化学战剂。戴维斯团队寻求通过提高IMS快速分离复杂现实世界混合物的能力来扩大IMS的有用性。这项研究主要是由惠特沃斯的本科生在戴维斯教授的指导下进行的。通过与华盛顿州立大学的Brian H.Clowers合作，戴维斯博士的学生可以接触到研究生院的环境，帮助他们为攻读研究生做好更好的准备。研究机会还扩展到华盛顿州大斯波坎地区的当地分析化学家社区，将工业和学术化学家聚集在一起，为学生和社区带来互惠互利。之前在创建电压扫描(VS)IMS分离方面的努力利用了阶跃电势或多路VS方法，这些方法无法达到许多IMS应用所需的高分辨率或高速分离。使用基于印刷电路板的IMS单元(利用最小的电路跟踪来减少电容)和应用高压放大器(能够达到500 V/ms的转换速率)，可以实现单次运行的VSIMS方法，从而显著提高IMS分辨率和峰值容量。通过使用脉冲电离源和消除离子门，可以减轻在低场条件下通过选通过程的离子的寄生损耗。主要目标是(1)开发一种使用高压放大器的单次运行的VSIMS方法，以实现高分辨率、高峰容量的IMS分离；(2)从离子形成、动力学和物种形成方面评估IMS和质谱仪(MS)的脉冲电离源的效用；以及(3)在IMS分离中使用脉冲源，以避免低场电压扫描条件下的栅极耗尽效应。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Eric Davis and his group at Whitworth University are working to improve the capabilities of ion mobility spectrometry (IMS), a chemical measurement technique commonly used in security and military applications for the detection of explosives, narcotics, and chemical warfare agents. The Davis group seeks to expand the usefulness of IMS by improving its ability to separate complex, real-world mixtures rapidly. The research is primarily performed by Whitworth undergraduate students under the supervision of Professor Davis. Through collaboration with Brian H. Clowers at Washington State University, Dr. Davis' students are exposed to the graduate school environment, helping to better prepare them to pursue graduate studies. Research opportunities also expand into the local community of analytical chemists within the greater Spokane, WA area, bringing together industrial and academic chemists for the mutual benefit of students and the community.Prior efforts in creating voltage sweep (VS) IMS separations have utilized either stepped-potential or multiplexed VS methods that do not attain the high-resolution or high-speed separations required for many IMS applications. Utilization of printed circuit board-based IMS cells (with minimal circuit tracing to reduce capacitance) and application of high voltage amplifiers (capable of 500 V/ms slew rates) enable single-run VSIMS methods which can provide significant improvements in IMS resolution and peak capacity. Parasitic losses of ions through the gating process under low-field conditions can be mitigated through use of pulsed ionization sources and elimination of the ion gate. Primary aims are to (1) develop a single-run VSIMS method using high voltage amplifiers to allow high resolution, high peak capacity IMS separations; (2) evaluate the utility of pulsed ionization sources with both IMS and mass spectrometry (MS) with respect to ion formation, kinetics, and speciation; and (3) utilize pulsed sources in IMS separations to avoid gate depletion effects under low-field voltage sweep conditions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.