Detection of Triacetone Triperoxide by High Kinetic Energy Ion Mobility Spectrometry
C. Schäfer, Martin Lippmann, Michiel Beukers, Niels Beijer, Ben van de Kamp, Jaap Knotter, Stefan Zimmermann
Abstract
High Resolution Image Download MS PowerPoint Slide High Kinetic Energy Ion Mobility Spectrometry (HiKE-IMS) is a versatile technique for the detection of gaseous target molecules that is particularly useful in complex chemical environments, while the instrumental effort is low. Operating HiKE-IMS at reduced pressures from 10 to 60 mbar results in fewer ion-neutral collisions than at ambient pressure, reducing chemical cross-sensitivities and eliminating the need for a preceding separation dimension, e.g., by gas chromatography. In addition, HiKE-IMS allows operation over a wide range of reduced electric field strengths E / N up to 120 Td, allowing separation of ions by low-field ion mobility and exploiting the field dependence of ion mobility, potentially allowing separation of ion species at high E / N despite similar low-field ion mobilities. Given these advantages, HiKE-IMS can be a useful tool for trace gas analysis such as triacetone triperoxide (TATP) detection. In this study, we employed HiKE-IMS to detect TATP. We explore the ionization of TATP and the field-dependent ion mobilities, providing a database of the ion mobilities depending on E / N . Confirming the literature results, ionization of TATP by proton transfer with H 3 O + in HiKE-IMS generates fragments, but using NH 4 + as the primary reactant ion leads to the TATP·NH 4 + adduct. This adduct fragments at high E / N, which could provide additional information for reliable detection of TATP. Thus, operating HiKE-IMS at variable E / N in the drift region generates a unique fingerprint of TATP made of all ion species related to TATP and their ion mobilities depending on E / N, potentially reducing the rate of false positives.