TY - JOUR

T1 - Revealing the Ion Chemistry Occurring in High Kinetic Energy-Ion Mobility Spectrometry

T2 - A Proof of Principle Study

AU - Weiss, Florentin

AU - Schaefer, Christoph

AU - Zimmermann, Stefan

AU - Märk, Tilmann D.

AU - Mayhew, Chris A.

N1 - Funding Information: We wish to acknowledge the EU HORIZON Innovation Actions HORIZON CL3-2021-DRS-01-05, Project Number 101073924 (ONELAB), for funding this project. Open access funding was provided by the University of Innsbruck.

PY - 2023/4/23

Y1 - 2023/4/23

N2 - Here, we present proof of principle studies to demonstrate how the product ions associated with the ion mobility peaks obtained from a High Kinetic Energy-Ion Mobility Spectrometer (HiKE-IMS) measurement of a volatile can be identified using a Proton Transfer Reaction/Selective Reagent Ion-Time-of-Flight-Mass Spectrometer (PTR/SRI-ToF-MS) when operating both instruments at the same reduced electric field value and similar humidities. This identification of product ions improves our understanding of the ion chemistry occurring in the ion source region of a HiKE-IMS. The combination of the two analytical techniques is needed, because in the HiKE-IMS three reagent ions (NO+, H3O+ and O2+•) are present at the same time in high concentrations in the reaction region of the instrument for reduced electric fields of 100 Td and above. This means that even with a mass spectrometer coupled to the HiKE-IMS, the assignment of the product ions to a given reagent ion to a high level of confidence can be challenging. In this paper, we demonstrate an alternative approach using PTR/SRI-ToF-MS that allows separate investigations of the reactions of the reagent ions NO+, H3O+ and O2+•. In this study, we apply this approach to four nitrile containing organic compounds, namely acetonitrile, 2-furonitrile, benzonitrile and acrylonitrile. Both the HiKE-IMS and the PTR/SRI-ToF-MS instruments were operated at a commonly used reduced electric field strength of 120 Td and with gas flows at the same humidities.

AB - Here, we present proof of principle studies to demonstrate how the product ions associated with the ion mobility peaks obtained from a High Kinetic Energy-Ion Mobility Spectrometer (HiKE-IMS) measurement of a volatile can be identified using a Proton Transfer Reaction/Selective Reagent Ion-Time-of-Flight-Mass Spectrometer (PTR/SRI-ToF-MS) when operating both instruments at the same reduced electric field value and similar humidities. This identification of product ions improves our understanding of the ion chemistry occurring in the ion source region of a HiKE-IMS. The combination of the two analytical techniques is needed, because in the HiKE-IMS three reagent ions (NO+, H3O+ and O2+•) are present at the same time in high concentrations in the reaction region of the instrument for reduced electric fields of 100 Td and above. This means that even with a mass spectrometer coupled to the HiKE-IMS, the assignment of the product ions to a given reagent ion to a high level of confidence can be challenging. In this paper, we demonstrate an alternative approach using PTR/SRI-ToF-MS that allows separate investigations of the reactions of the reagent ions NO+, H3O+ and O2+•. In this study, we apply this approach to four nitrile containing organic compounds, namely acetonitrile, 2-furonitrile, benzonitrile and acrylonitrile. Both the HiKE-IMS and the PTR/SRI-ToF-MS instruments were operated at a commonly used reduced electric field strength of 120 Td and with gas flows at the same humidities.

KW - chemical ionization

KW - HiKE-IMS

KW - ion–molecule reactions

KW - nitriles

KW - PTR/SRI-ToF-MS

UR - http://www.scopus.com/inward/record.url?scp=85168014481&partnerID=8YFLogxK

U2 - 10.3390/analytica4020010

DO - 10.3390/analytica4020010

M3 - Article

AN - SCOPUS:85168014481

VL - 4

SP - 113

EP - 125

JO - Analytica

JF - Analytica

IS - 2

ER -