TY  - JOUR
A1  - Riebe, Daniel
A1  - Laudien, Robert
A1  - Brendler, Christian
A1  - Beitz, Toralf
A1  - Löhmannsröben, Hans-Gerd
T1  - Laser ionization of H2S and ion-molecule reactions of H3S+ in laser-based ion mobility spectrometry and drift cell time-of-flight mass spectrometry
JF  - Analytical & bioanalytical chemistry
N2  - The detection of hydrogen sulfide (H2S) by 2 + 1 resonance-enhanced multi-photon ionization (REMPI) and the application of H2S as a laser dopant for the detection of polar compounds in laser ion mobility (IM) spectrometry at atmospheric pressure were investigated. Underlying ionization mechanisms were elucidated by additional studies employing a drift cell interfaced to a time-of-flight mass spectrometer. Depending on the pressure, the primary ions H2S+, HS+, S+, and secondary ions, such as H3S+, were observed. The 2 + 1 REMPI spectrum of H2S near lambda = 302.5 nm was recorded at atmospheric pressure. Furthermore, the limit of detection and the linear range were established. In the second part of the work, H2S was investigated as an H2O analogous laser dopant for the ionization of polar substances by proton transfer. H2S exhibits a proton affinity (PA) similar to that of H2O, but a significantly lower ionization energy facilitating laser ionization. Ion-molecule reactions (IMR) of H3S+ with a variety of polar substances with PA between 754.6 and 841.6 kJ/mol were investigated. Representatives of different compound classes, including alcohols, ketones, esters, and nitroaromatics were analyzed. The IM spectra resulting from IMR of H3S+ and H3O+ with these substances are similar in structure, i.e., protonated monomer and dimer ion peaks are found depending on the analyte concentration.
KW  - Ion mobility spectrometry
KW  - Mass spectrometry
KW  - REMPI
KW  - Hydrogen sulfide
KW  - Proton transfer reaction
Y1  - 2013
U6  - https://doi.org/10.1007/s00216-013-7186-5
SN  - 1618-2642
VL  - 405
IS  - 22
SP  - 7031
EP  - 7039
PB  - Springer
CY  - Heidelberg
ER  -