A miniaturized low-cost ion mobility spectrometer for fast detection of trace gases in air

In this paper we present an optimized design of our miniaturized ion mobility spectrometer. It has significantly improved analytical capabilities compared to our previous prototypes, and it can be manufactured at low cost by simply stacking four easy-to-manufacture parts. Different gases were measured down to low ppb-level concentrations in air to demonstrate the analytical performance. The system was challenged with Dimethyl methylphosphonate, Diisopropyl methylphosphonate, Diethyl cyanophosphonate, 2-Chloroethyl ethyl sulfide, Methyl caproate and 1-Octanol. The resolution of our miniaturized IMS is now sufficient to partly resolve different product ion peaks. However, substance identification by peak position is still difficult. Therefore, a simple pattern recognition algorithm is used for substance identification. Reliable identification of single substances is possible down to low ppb-level concentrations within 3 seconds.