Voltage Sweep Ion Mobility Spectrometry

Abstract

Ion mobility spectrometry (IMS), is a powerful tool commonly used for security applications (e.g. search for explosives, narcotics, and other trace contrabands) but it doesn’t achieve optimal separation power with both small and large ions simultaneously. Similar to the general elution problem of chromatographic experiments, small ions are well resolved using a low electric field, whereas large molecules are best separated using a higher electric field. While using a low electric field, IMS systems tend to suffer from low ion transmission and low signal-to-noise ratios.

Washington State University scientists have alleviated these effects using a software-created second gate and a novel voltage algorithm. The electric field was swept from low to high while monitoring a specific drift time using the second gate creating a ‘voltage-sweep’ spectrum. This not only increases the resolving power of each peak in the spectrum, but also allows simultaneous separation of peaks for both low and high mobility compounds.

Applications and Advantages

•Vast Improvement over analysis time

•Improved resolving power

•Extends peak capacity of any IMS system

•Minimal implementation cost

•Generates more detailed information when compared to a standard IMS system

Patent# 13/163,568