Isoflurane as an Accurate Negative Mode Calibrant for Ion Mobility Spectrometry

The search for suitable ion mobility spectrometry (IMS) calibrant compounds is ongoing and necessitates the use of highly accurate reduced ion mobility (K-0) values across a range of instrumental conditions. Such values will be used in calibrating devices to shift the ion mobility scales and alarm windows for chemicals of interest to their proper locations based on the instrumental conditions present during calibration and sampling. Many positive ion mode calibrants have been investigated, whereas investigations for a negative ion detection mode calibrant have been more limited. Isoflurane (IsoF) is a strong candidate as a negative ion mode calibrant. This report documents the accurately measured K-0 values for IsoF product ions as a function of multiple instrumental parameters. K-0 values were measured in two instrumentation modes as a function of drift gas temperature, water concentration, and dopant concentration. This report culminates with our evaluation of the suitability of IsoF as a negative ion mode calibrant for IMS applications.

Automated summary

The search for suitable ion mobility spectrometry (IMS) calibrant compounds continues, with a focus on accurately measuring reduced ion mobility (K-0) values under various instrumental conditions. Isoflurane (IsoF) is highlighted as a strong candidate for negative ion mode calibrant, and its accurately measured K-0 values are discussed in this report. The evaluation of IsoF as a negative ion mode calibrant for IMS applications is the main focus of this study.