Structure selective ion molecule interactions (SSIMI)

Ion mobility spectrometry (IMS) is commonly used for the detection of chemical warfare agents, toxic industrial chemicals and drugs of abuse testing, but has a reputation of false positive responses. This paper demonstrates the use of HPIMS to lower false positive alerts by using .structure selective ion molecule interactions (SSIMI) to shift the mobility of a targeted analyte through the addition of a gas phase modifier to the buffer gas. A series of buffer gas modifiers were evaluated to enhance the separation of chemical warfare agent simulants (CWAs), toxic industrial chemicals (TICs) and a known interference (butyl carbitol) found in fire extinguishing agents.