Pulsed Ion Mobility Spectrometer for the Detection of Toluene 2, 4-Diisocyanate in Ambient Air

In this paper, we use an ion mobility spectrometer with a nonradioactive ionization source that can be operated in pulsed mode, which offers the advantage of introducing delay times after the ionization. These allow the observation of substance specific signal decay times which can enhance the selectivity. The described novel principle can be used in the detection of the hazardous substance toluene 2,4-diisocyanate (TDI) in e.g., industrial areas since it offers the required sensitivity and selectivity with response times of only a few minutes. This will be shown with a focus on the TDI signal's decay characteristics regarding changes of concentration and humidity.