TY  - JOUR
AB  - Peatland fires emit organic carbon-rich particulate matter into the atmosphere. Boreal and Arctic peatlands are becoming more vulnerable to wildfires, resulting in a need for better understanding of the emissions of these special fires. Extractable, nonpolar, and low-polar organic aerosol species emitted from laboratory-based boreal and Arctic peat-burning experiments are analyzed by direct-infusion atmospheric pressure photoionization (APPI) ultrahigh-resolution mass spectrometry (UHRMS) and compared to time-resolved APPI UHRMS evolved gas analysis from the thermal analysis of peat under inert nitrogen (pyrolysis) and oxidative atmosphere. The chemical composition is characterized on a molecular level, revealing abundant aromatic compounds that partially contain oxygen, nitrogen, or sulfur and are formed at characteristic temperatures. Two main structural motifs are identified, single core and multicore, and their temperature-dependent formation is assigned to the thermal degradation of the lignocellulose building blocks and other parts of peat.
AU  - Schneider, E.*
AU  - Neumann, A.*
AU  - Chacón-Patiño, M.L.*
AU  - Somero, M.*
AU  - Ruppel, M.M.*
AU  - Ihalainen, M.*
AU  - Köster, K.*
AU  - Sippula, O.*
AU  - Czech, H.
AU  - Rüger, C.P.*
AU  - Zimmermann, R.
C1  - 71024
C2  - 55988
CY  - 1155 16th St, Nw, Washington, Dc 20036 Usa
TI  - Accessing the low-polar molecular composition of boreal and arctic peat-burning organic aerosol via thermal analysis and ultrahigh-resolution mass spectrometry: Structural motifs and their formation.
JO  - J. Am. Soc. Mass Spectrom.
PB  - Amer Chemical Soc
PY  - 2024
ER  - 

TY  - JOUR
AB  - We introduce vacuum resonance-enhanced multiphoton ionization (REMPI) with high-resolution Orbitrap Fourier transform mass spectrometry (FTMS) for analyzing silylated polar compounds. UV laser radiation at 248 nm sensitively and selectively targets aromatic constituents, while high-resolution mass spectrometry (HRMS) enables high-performance mass spectrometric detection. This workflow enhances the detection confidence of polar constituents by identifying unique isotopologue patterns, including at the isotopic fine structure (IFS) level, in analytical standards and complex bio-oils. A direct and derivatized gas chromatography (GC) procedure on a polar standard component mixture allowed us to explore the general ionization and detection characteristics of REMPI FTMS. HRMS enabled the examination of the complex isotopologue profiles, revealing distinct patterns for the CHOxSiy-class compounds. Particularly in complex mixtures, this isobaric/isonucleonic complexity exceeded the classical mass resolution capabilities of the employed Orbitrap D30 series and prompted the usage of prolonged transients via an external data acquisition system. This procedure substantially improved mass spectrometric results by recording the unreduced time-domain transient data for up to 2 s. Notably, the ability to distinguish diagnostic isotopic pairs, such as 12C/29Si vs 13C/28Si with a mass split of ∼3.79 mDa and 13C12C/28Si29Si vs 13C2/28Si2, with an approximate mass difference of ∼3.32 mDa, demonstrates a significant and expected performance improvement. Finally, we benchmark the GC HRMS methodology to identify silylated oxygenated and nitrogen-containing constituents in ultracomplex bio-oil samples. The presented approach of utilizing the silicon isotope pattern and unique isotopologue mass splits for increasing attribution confidence can be applied beyond bio-oils toward the general GC analyses of polar oxygenates.
AU  - Vesga Martínez, S.J.*
AU  - Rüger, C.P.*
AU  - Kösling, P.*
AU  - Schade, J.*
AU  - Ehlert, S.*
AU  - Tsybin, Y.O.*
AU  - Zimmermann, R.
C1  - 72298
C2  - 56563
CY  - 1155 16th St, Nw, Washington, Dc 20036 Usa
SP  - 3242-3255
TI  - Deciphering isotopic fine structures of silylated compounds in gas chromatography-vacuum photoionization orbitrap mass spectrometry of bio-oils.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 35
IS  - 12
PB  - Amer Chemical Soc
PY  - 2024
ER  - 

TY  - JOUR
AB  - Photoionization schemes for mass spectrometry, either by laser or discharge lamps, have been widely examined and deployed. In this work, the ionization characteristics of a xenon discharge lamp (Xe-APPI, 9.6/8.4 eV) have been studied and compared to established ionization schemes, such as atmospheric pressure chemical ionization, atmospheric pressure photoionization with a krypton discharge lamp (Kr-APPI, 10.6/10 eV) and atmospheric pressure laser ionization (266 nm). Addressing the gas-phase ionization behavior has been realized by gas chromatography coupled to high-resolution mass spectrometry without the usage of a dopant. For standard substances, it has been found that Xe-APPI is able to ionize a broad range of polycyclic aromatic hydrocarbons as well as their heteroatom-containing and alkylated derivatives. However, thiol and ester compounds could not be detected. Moreover, Xe-APPI revealed a high tendency to generate oxygenated artifacts, most likely due to a VUV absorption band of oxygen at 148 nm. Beneficially, almost no chemical background, commonly caused by APCI or Kr-APPI due to column blood, plasticizers or impurities, is observed. This advantage is noteworthy for evolved gas analysis without preseparation or for chromatographic coelution. For the complex mixtures, Xe-APPI revealed the predominant generation of radical cations via direct photoionization with a high selectivity toward aromatic core structures with low alkylation. Interestingly, both Xe-APPI and Kr-APPI could sensitively detect sterane cycloalkanes, validated by gas chromatographic retention. The narrowly ionized chemical space could let Xe-APPI find niche applications, e.g., for strongly contaminated samples to reduce the background.
AU  - Neumann, A.*
AU  - Tiemann, O.*
AU  - Hansen, H.J.*
AU  - Rüger, C.*
AU  - Zimmermann, R.
C1  - 68405
C2  - 54637
CY  - 1155 16th St, Nw, Washington, Dc 20036 Usa
SP  - 1632-1646
TI  - Detailed comparison of Xenon APPI (9.6/8.4 eV), Krypton APPI (10.6/10.0 eV), APCI, and APLI (266 nm) for gas chromatography high resolution mass spectrometry of standards and complex mixtures.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 34
IS  - 8
PB  - Amer Chemical Soc
PY  - 2023
ER  - 

TY  - JOUR
AB  - Ultrahigh resolution mass spectrometry (UHR-MS) coupled with direct infusion (DI) electrospray ionization offers a fast solution for accurate untargeted profiling. Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometers have been shown to produce a wealth of insights into complex chemical systems because they enable unambiguous molecular formula assignment even if the vast majority of signals is of unknown identity. Interlaboratory comparisons are required to apply this type of instrumentation in quality control (for food industry or pharmaceuticals), large-scale environmental studies, or clinical diagnostics. Extended comparisons employing different FT-ICR MS instruments with qualitative direct infusion analysis are scarce since the majority of detected compounds cannot be quantified. The extent to which observations can be reproduced by different laboratories remains unknown. We set up a preliminary study which encompassed a set of 17 laboratories around the globe, diverse in instrumental characteristics and applications, to analyze the same sets of extracts from commercially available standard human blood plasma and Standard Reference Material (SRM) for blood plasma (SRM1950), which were delivered at different dilutions or spiked with different concentrations of pesticides. The aim of this study was to assess the extent to which the outputs of differently tuned FT-ICR mass spectrometers, with different technical specifications, are comparable for setting the frames of a future DI-FT-ICR MS ring trial. We concluded that a cluster of five laboratories, with diverse instrumental characteristics, showed comparable and representative performance across all experiments, setting a reference to be used in a future ring trial on blood plasma.
AU  - Forcisi, S.
AU  - Moritz, F.
AU  - Thompson, C.J.*
AU  - Kanawati, B.
AU  - Uhl, J.
AU  - Afonso, C.*
AU  - Bader, C.D.*
AU  - Barsch, A.*
AU  - Boughton, B.A.*
AU  - Chu, R.K.*
AU  - Ferey, J.*
AU  - Fernandez-Lima, F.*
AU  - Guéguen, C.*
AU  - Heintz, D.*
AU  - Gomez-Hernandez, M.*
AU  - Jang, K.S.*
AU  - Kessler, N.*
AU  - Mangal, V.*
AU  - Müller, R.*
AU  - Nakabayashi, R.*
AU  - Nicol, E.*
AU  - Nicolardi, S.*
AU  - Palmblad, M.*
AU  - Paša-Tolić, L.*
AU  - Porter, J.*
AU  - Schmitz-Afonso, I.*
AU  - Seo, J.B.*
AU  - Sommella, E.*
AU  - van der Burgt, Y.E.M.*
AU  - Villette, C.*
AU  - Witt, M.*
AU  - Wittrig, A.*
AU  - Wolff, J.J.*
AU  - Easterling, M.L.*
AU  - Laukien, F.H.*
AU  - Schmitt-Kopplin, P.
C1  - 66674
C2  - 53276
SP  - 2203–2214
TI  - Large-scale interlaboratory DI-FT-ICR MS comparability study employing various systems.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 33
IS  - 12
PY  - 2022
ER  - 

TY  - JOUR
AB  - The detection of polycyclic aromatic hydrocarbons (PAHs) by electrospray ionization (ESI) without additional reagents or targeted setup changes to the ionization source was observed in ultrafine particle (UFP) extracts, with high organic carbon (OC) concentrations, generated by a combustion aerosol standard (CAST) soot generator. Particulate matter (PM) was collected on filters, extracted with methanol, and analyzed by ESI Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Next to oxygen-containing species, pure hydrocarbons were found to be one of the most abundant compound classes, detected as [M + Na]+ or [M + H]+ in ESI+ and mostly as [M - H]- in ESI-. The assigned hydrocarbon elemental compositions are identified as PAHs due to their high aromaticity index (AI > 0.67) and were additionally confirmed by MS/MS experiments as well as laser desorption ionization (LDI). Thus, despite the relatively low polarity, PAHs have to be considered in the molecular attribution of these model aerosols and/or fresh emissions with low salt content investigated by ESI.
AU  - Schneider, E.*
AU  - Giocastro, B.*
AU  - Rüger, C.P.*
AU  - Adam, T.
AU  - Zimmermann, R.
C1  - 66355
C2  - 53147
SP  - 2019–2023
TI  - Detection of polycyclic aromatic hydrocarbons in high organic carbon ultrafine particle extracts by electrospray ionization ultrahigh-resolution mass spectrometry.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 33
IS  - 11
PY  - 2022
ER  - 

TY  - JOUR
AB  - Anthropogenic air pollution has a severe impact on climate and human health. The immense molecular complexity and diversity of particulate matter (PM) is a result of primary organic aerosol (POA) as well as secondary organic aerosols (SOAs). In this study, a direct inlet probe (DIP), i.e., atmospheric solids analysis probe (ASAP), with ion mobility high-resolution mass spectrometric detection is applied. Primary particulate matter emissions from three sources were investigated. Furthermore, photochemically aged emissions were analyzed. DIP introduction allowed for a direct analysis with almost no sample preparation and resulted in a complex molecular pattern. This pattern shifted through oxidation processes toward heavier species. For diesel emissions, the fuel's chemical characteristic is partially transferred to the particulate matter by incomplete combustion and characteristic alkylated series were found. Polycyclic aromatic hydrocarbons (PAHs) were identified as major contributors. Ion mobility analysis results in drift time profiles used for structural analysis. The apex position was used to prove structural changes, whereas the full-width-at-half-maximum was used to address the isomeric diversity. With this concept, the dominance of one or a few isomers for certain PAHs could be shown. In contrast, a broad isomeric diversity was found for oxygenated species. For the in-depth specification of fresh and aged spruce emissions, the ion mobility resolving power was almost doubled by allowing for three passes in the circular traveling wave design. The results prove that ASAP coupled with ion mobility spectrometry-mass spectrometry (IMS-MS) serves as a promising analytical approach for tackling the vast molecular complexity of PM.
AU  - Rüger, C.P.*
AU  - Le Maître, J.*
AU  - Riches, E.*
AU  - Palmer, M.*
AU  - Orasche, J.
AU  - Sippula, O.*
AU  - Jokiniemi, J.*
AU  - Afonso, C.*
AU  - Giusti, P.*
AU  - Zimmermann, R.
C1  - 60639
C2  - 49555
CY  - 1155 16th St, Nw, Washington, Dc 20036 Usa
SP  - 206-217
TI  - Cyclic ion mobility spectrometry coupled to high-resolution time-of-flight mass spectrometry equipped with atmospheric solid analysis probe for the molecular characterization of combustion particulate matter.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 32
IS  - 1
PB  - Amer Chemical Soc
PY  - 2021
ER  - 

TY  - JOUR
AB  - The rising demand for more and more specialized polyethylene represents a challenge for synthesis and analysis. The desired properties are dependent on the structure, but its elucidation is still intricate. For this purpose, we applied thermal analysis hyphenated to single photon ionization mass spectrometry (STA-SPI-MS). The melting and pyrolysis behavior of different types of polyethylene were tracked by DSC and mass loss. Crystallinity and melting point give hints about the branching but are also influenced by the molecular weight distribution. The evolving gas analysis patterns obtained by SPI-MS however, contain specific molecular information about the samples. Shifts in the summed spectra, which can be clearly observed with our technique, result from differently favored degradation reactions due to the respective structure. Pyrolysis gas chromatography mass spectrometry (Py-GC-EI-MS) was used to support the assignment of pyrolysis products. Principal component analysis was successfully applied to reduce the complexity of data and find suitable markers. The obtained grouping is based on the molecular fingerprint of the samples and is strongly influenced by short-chain branching. Short and medium alkenes and dienes have the strongest impact on the first four principal components. Thus, two marker ratios could be defined, which also give a comprehensible and robust grouping. Butene and pentene were the most abundant signals in our set of samples. With STA-PI-MS, a broad range of pyrolysis products can be measured at the same time, possibly extending the range for quantifiable short-chain branches to more than six carbon atoms for PE. Unfortunately, no clear trend between long-chain branching and any grouping was observed. The quite universal and soft single photon ionization enables access to many different compound classes and hence other polymers can be studied.
AU  - Grimmer, C.*
AU  - Friederici, L.*
AU  - Streibel, T.
AU  - Naim, A.*
AU  - Cirriez, V.*
AU  - Giusti, P.*
AU  - Afonso, C.*
AU  - Rüger, C.P.*
AU  - Zimmermann, R.
C1  - 60492
C2  - 49479
CY  - 1155 16th St, Nw, Washington, Dc 20036 Usa
SP  - 2362-2369
TI  - Characterization of polyethylene branching by thermal analysis-photoionization mass spectrometry.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 31
IS  - 11
PB  - Amer Chemical Soc
PY  - 2020
ER  - 

TY  - JOUR
AB  - A major bottleneck in metabolomics is the annotation of a molecular formula as a first step to a tentative structure assignment of known and unknown metabolites. The direct observation of an isotopic fine structure (IFS) provides the ability to confidently assign an unknown's molecular formula out of a complex mass spectrum. However, the majority of mass spectrometers deployed for metabolomic studies do not have sufficient resolving power and high-fidelity isotope ratios in the mass range of interest to determine molecular formulas from IFS data. To increase the number of unknowns for which IFS can be determined, a segmented "boxcar" approach using a selection quadrupole as a broadband mass filter is used. In this longer, enhanced dynamic range discovery experiment, selected ions in a specific mass range are accumulated before detection by the analyzer cell. The mass filter window is then moved across the entire mass range resulting in a composite mass spectrum covering the m/z range of interest for phenomics research. The effectiveness of the FIA-CASI-FTMS workflow utilizing IFS for molecular formula assignment is realized with the implementation of the dynamically harmonized cell, which distinguishes the approach from other segmented workflows because of the analytical properties of the cell. The discovery approach was applied to a human plasma sample to confidently assign an unknown molecular formula as part of the quest to illuminate its metabolic "dark matter" via high-fidelity IFS ratio determinations. The FIA-CASI-FTMS workflow showed a 2.6-fold increase in both matching with the Human Metabolome Database and an increase in the IFS pattern.
AU  - Thompson, C.J.*
AU  - Witt, M.*
AU  - Forcisi, S.
AU  - Moritz, F.
AU  - Kessler, N.*
AU  - Laukien, F.H.*
AU  - Schmitt-Kopplin, P.
C1  - 60326
C2  - 49323
CY  - 1155 16th St, Nw, Washington, Dc 20036 Usa
SP  - 2025-2034
TI  - An enhanced isotopic fine structure method for exact mass analysis in discovery metabolomics: FIA-CASI-FTMS.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 31
IS  - 10
PB  - Amer Chemical Soc
PY  - 2020
ER  - 

TY  - JOUR
AB  - Ammonia is well suited to favor deprotonation process in electrospray ionization mass spectrometry (ESI-MS) to increase the formation of [M - H]. Nevertheless, NH may react with carbonyl compounds (aldehyde, ketone) and bias the composition description of the investigated sample. This is of significant importance in the study of complex mixture such as oil or bio-oil. To assess the ability of primary amines to form imines with carbonyl compounds during the ESI-MS process, two aldehydes (vanillin and cinnamaldehyde) and two ketones (butyrophenone and trihydroxyacetophenone) have been infused in an ESI source with ammonia and two different amines (aniline and 3-chloronaniline). The (+) ESI-MS analyses have demonstrated the formation of imine whatever the considered carbonyl compound and the used primary amine, the structure of which was extensively studied by tandem mass spectrometry. Thus, it has been established that the addition of ammonia, in the solution infused in an ESI source, may alter the composition description of a complex mixture and leads to misinterpretations due to the formation of imines. Nevertheless, this experimental bias can be used to identify the carbonyl compounds in a pyrolysis bio-oil. As we demonstrated, infusion of the bio-oil with 3-chloroaniline in ESI source leads to specifically derivatized carbonyl compounds. Thanks to their chlorine isotopic pattern and the high mass measurement accuracy, (+) ESI Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) unambiguously highlighted them from the numerous CHO bio-oil components. These results offer a new perspective into the detailed molecular structure of complex mixtures such as bio-oils.
AU  - Hertzog, J.*
AU  - Carré, V.*
AU  - Dufour, A.*
AU  - Aubriet, F.*
C1  - 54674
C2  - 0
SP  - 543-557
TI  - Semi-targeted analysis of complex matrices by ESI FT-ICR MS or how an experimental bias may be used as an analytical tool.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 29
IS  - 3
PY  - 2018
ER  - 

TY  - JOUR
AB  - Mass spectrometry faces considerable difficulties in de novo sequencing of long non-tryptic peptides with S-S bonds. Long disulfide-containing peptides brevinins 1E and 2Ec from frog Rana ridibunda were reduced and alkylated with nine novel and three known derivatizing agents. Eight of the novel reagents are maleimide derivatives. Modified samples were subjected to MS/MS studies on FT-ICR and Orbitrap mass spectrometers using CAD/HCD or ECD/ETD techniques. Procedures, fragmentation patterns, and sequence coverage for two peptides modified with 12 tags are described. ECD/ETD and CAD fragmentation revealed complementary sequence information. Higher-energy collisionally activated dissociation (HCD) sufficiently enhanced y-ions formation for brevinin 1E, but not for brevinin 2Ec. Some novel tags [N-benzylmaleimide, N-(2,6-dimethylphenyl)maleimide] along with known N-phenylmaleimide and iodoacetic acid showed high total sequence coverage taking into account combined ETD and HCD fragmentation. Moreover, modification of long (34 residues) brevinin 2Ec with N-benzylmaleimide or N-(2,6-dimethylphenyl)maleimide yielded high sequence coverage and full C-terminal sequence determination with ECD alone.
AU  - Samgina, T.Y.*
AU  - Vorontsov, E.A.*
AU  - Gorshkov, V.A.*
AU  - Artemenko, K.A.*
AU  - Nifant'ev, I.E.*
AU  - Kanawati, B.
AU  - Schmitt-Kopplin, P.
AU  - Zubarev, R.A.*
AU  - Lebedev, A.T.*
C1  - 5625
C2  - 29159
SP  - 2246-2255
TI  - Novel cysteine tags for the sequencing of non-tryptic disulfide peptides of anurans: ESI-MS study of fragmentation efficiency.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 22
IS  - 12
PB  - Springer
PY  - 2011
ER  - 

TY  - JOUR
AU  - Wittmaack, K.
AU  - Szymczak, W.
AU  - Hoheisel, G.*
AU  - Tuszynski, W.*
C1  - 22192
C2  - 20901
SP  - 553-563
TI  - Time-of-flight secondary ion mass spectrometry of matrix-diluted oligo- and polypeptides bombarded with slow and fast projectiles : Positive and negative matrix and analyte ion yields, background signals and sample aging.
JO  - J. Am. Soc. Mass Spectrom.
VL  - 11
PY  - 2000
ER  -