Ion Mobility Spectrometry

This chapter discusses ion mobility spectrometry (IMS) with a focus on interfacing IMS. Ions moving in a gas are accelerated due to coulomb forces in the presence of the electric field and slowed down by collisions with gas molecules. The chapter summarizes the different modes of IMS: drift time, high-field asymmetric waveform, travelling wave, and trapped. With drift time- or temporally-dispersive IMS, the ions drift along a similar path and arrive at the detector at different times, thereby producing peaks as a function of time. The chapter outlines the aspect of resolving power in MS, and discusses the interfacing IMS; interfacing with MS allows analysis of complex mixtures, providing structural information and increased peak capacity. It also discusses the various applications of IMS in analytical toxicology: direct analysis, interfaced techniques, and chiral separations.