Ultra-fast polarity switching ion mobility spectrometer

It is well known that depending on their gas phase energetic properties, different substances may form positive ions, negative ions or even ions of both polarities in some cases. Thus, non-targeted measurements or measurements aiming to monitor a variety of substances require analyzing ions of both polarities, e.g. in GC-IMS applications. In this project, an ion mobility spectrometer which is able to perform a polarity switch in less than 10 ms has been developed. This allows switching the measurement polarity after every spectrum, thus enabling real-time monitoring of ions of both polarities with a single drift tube and obviating the need for expensive twin drift tubes.