1
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Bouwmeester R, Richardson K, Denny R, Wilson ID, Degroeve S, Martens L, Vissers JPC. Predicting ion mobility collision cross sections and assessing prediction variation by combining conventional and data driven modeling. Talanta 2024; 274:125970. [PMID: 38621320 DOI: 10.1016/j.talanta.2024.125970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 03/01/2024] [Accepted: 03/20/2024] [Indexed: 04/17/2024]
Abstract
The use of collision cross section (CCS) values derived from ion mobility studies is proving to be an increasingly important tool in the characterization and identification of molecules detected in complex mixtures. Here, a novel machine learning (ML) based method for predicting CCS integrating both molecular modeling (MM) and ML methodologies has been devised and shown to be able to accurately predict CCS values for singly charged small molecular weight molecules from a broad range of chemical classes. The model performed favorably compared to existing models, improving compound identifications for isobaric analytes in terms of ranking and assigning identification probability values to the annotation. Furthermore, charge localization was seen to be correlated with CCS prediction accuracy and with gas-phase proton affinity demonstrating the potential to provide a proxy for prediction error based on chemical structural properties. The presented approach and findings represent a further step towards accurate prediction and application of computationally generated CCS values.
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Affiliation(s)
- Robbin Bouwmeester
- VIB-UGent Center for Medical Biotechnology, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent, Belgium.
| | | | | | - Ian D Wilson
- Computational & Systems Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College, United Kingdom
| | - Sven Degroeve
- VIB-UGent Center for Medical Biotechnology, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Lennart Martens
- VIB-UGent Center for Medical Biotechnology, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
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2
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Liu W, Liu F, Che A, Chen Y, Cai J, Liu W, Jing G, Li W, Yu J. Investigation of low-temperature partitioning with dispersive solid-phase extraction for quantification of pesticides in apples followed by electrospray-ionization mobility spectrometry: Comparison with conventional procedure. J Chromatogr B Analyt Technol Biomed Life Sci 2024; 1234:124014. [PMID: 38306956 DOI: 10.1016/j.jchromb.2024.124014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/06/2024] [Accepted: 01/14/2024] [Indexed: 02/04/2024]
Abstract
Ion mobility spectrometry (IMS) has a promising application prospect in food surveillance. However, due to the complexity of food matrix and trace levels of pesticide residues, the effective and rapid detection of pesticides by IMS has been a challenge, especially when using electrospray ionization (ESI) as an ion source. In this study, low-temperature partitioning with dispersive solid-phase extraction (LTP-dSPE) was explored and compared with conventional procedures. Both methods were validated for the quantification of eight pesticides in apples, obtaining a limit of detection (LOD) of 0.02-0.12 mg/kg for LTP-dSPE and 0.02-0.09 mg/kg for conventional solid-phase extraction (SPE), lower than those usually stipulated by government legislation in food matrices. For LTP-dSPE, the matrx effect (ME) ranged from -16.3 to -68.6 %, lower than that for the SPE method, ranging from -70.0 to -92.9 %. The results showed satisfactory efficiency and precision, with recovery values ranging from 67.9 to 115.4 % for LTP-dSPE and from 62.0 to 114.8 % for conventional SPE, with relative standard deviations below 13.0 %. Notably, the proposed LTP-dSPE/ESI-IMS has been shown to be more cost-effective, easier to use, more environment-friendly, more accessible, and, most importantly, less matrix effect than the conventional method, thereby being suitably applicable to a wide range of food safety applications.
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Affiliation(s)
- Wen Liu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China.
| | - Fei Liu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Anyi Che
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Yanjing Chen
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Jiayi Cai
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Wenjie Liu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Guoxing Jing
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Wenshan Li
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Jianna Yu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China.
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3
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Duez Q, Hoyas S, Josse T, Cornil J, Gerbaux P, De Winter J. Gas-phase structure of polymer ions: Tying together theoretical approaches and ion mobility spectrometry. MASS SPECTROMETRY REVIEWS 2023; 42:1129-1151. [PMID: 34747528 DOI: 10.1002/mas.21745] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 08/17/2021] [Accepted: 08/23/2021] [Indexed: 06/07/2023]
Abstract
An increasing number of studies take advantage of ion mobility spectrometry (IMS) coupled to mass spectrometry (IMS-MS) to investigate the spatial structure of gaseous ions. Synthetic polymers occupy a unique place in the field of IMS-MS. Indeed, due to their intrinsic dispersity, they offer a broad range of homologous ions with different lengths. To help rationalize experimental data, various theoretical approaches have been described. First, the study of trend lines is proposed to derive physicochemical and structural parameters. However, the evaluation of data fitting reflects the overall behavior of the ions without reflecting specific information on their conformation. Atomistic simulations constitute another approach that provide accurate information about the ion shape. The overall scope of this review is dedicated to the synergy between IMS-MS and theoretical approaches, including computational chemistry, demonstrating the essential role they play to fully understand/interpret IMS-MS data.
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Affiliation(s)
- Quentin Duez
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | - Sébastien Hoyas
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | | | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | - Pascal Gerbaux
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | - Julien De Winter
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
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4
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Fu D, Habtegabir SG, Wang H, Feng S, Han Y. Understanding of protomers/deprotomers by combining mass spectrometry and computation. Anal Bioanal Chem 2023:10.1007/s00216-023-04574-1. [PMID: 36737499 DOI: 10.1007/s00216-023-04574-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/19/2023] [Accepted: 01/27/2023] [Indexed: 02/05/2023]
Abstract
Multifunctional compounds may form different prototropic isomers under different conditions, which are known as protomers/deprotomers. In biological systems, these protomer/deprotomer isomers affect the interaction modes and conformational landscape between compounds and enzymes and thus present different biological activities. Study on protomers/deprotomers is essentially the study on the acidity/basicity of each intramolecular functional group and its effect on molecular structure. In recent years, the combination of mass spectrometry (MS) and computational chemistry has been proven to be a powerful and effective means to study prototropic isomers. MS-based technologies are developed to discriminate and characterize protomers/deprotomers to provide structural information and monitor transformations, showing great superiority than other experimental methods. Computational chemistry is used to predict the thermodynamic stability of protomers/deprotomers, provide the simulated MS/MS spectra, infrared spectra, and calculate collision cross-section values. By comparing the theoretical data with the corresponding experimental results, the researchers can not only determine the protomer/deprotomer structure, but also investigate the structure-activity relationship in a given system. This review covers various MS methods and theoretical calculations and their devotion to isomer discrimination, structure identification, conformational transformation, and phase transition investigation of protomers/deprotomers.
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Affiliation(s)
- Dali Fu
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Sara Girmay Habtegabir
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Haodong Wang
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Shijie Feng
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Yehua Han
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China.
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5
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Analytical key issues and challenges in the LC-MS/MS determination of antibiotics in wastewater. Anal Chim Acta 2023; 1239:340739. [PMID: 36628733 DOI: 10.1016/j.aca.2022.340739] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 12/27/2022]
Abstract
The research on antibiotics occurrence in the aquatic environment has become a hot topic in the last years due to their potential negative effects, associated to possible bacterial antibiotic-resistance, after continuous exposure to these compounds. Most of antibiotic residues are not completely removed in the wastewater treatment plants (WWTPs) and end up in the aquatic environment through treated wastewater (WW). The development of reliable analytical methodologies for the determination of antibiotics in influent (IWW) and effluent wastewater (EWW) is needed with different purposes, among others: monitoring their occurrence in the aquatic environment, performing environmental risk assessment, estimating removal efficiencies of WWTPs, or estimating the consumption of these compounds. In this paper, we perform an in-depth investigation on analytical key issues that pose difficulties in the determination of antibiotics in complex matrices, such as WW, and we identify challenges to be properly addressed for successful analysis. The analytical technique selected was liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), as it is the most powerful and widely applied at present for antibiotic residues determination. The mass spectrometric behavior of 18 selected antibiotics, the chromatographic performance, ion ratio variations associated to the sample matrix when using different precursor ions or protomers, and the macrolides adsorption to glass vial, were some of the issues studied in this work. On the basis of the detailed study performed, an analytical LC-MS/MS method based on sample direct injection has been developed for quantification of 18 antibiotics in IWW and EWW, allowing their determination at low ng L-1 levels.
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6
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Vu OT, Nguyen QH, Nguy Phan T, Luong TT, Eersels K, Wagner P, Truong LTN. Highly Sensitive Molecularly Imprinted Polymer-Based Electrochemical Sensors Enhanced by Gold Nanoparticles for Norfloxacin Detection in Aquaculture Water. ACS OMEGA 2023; 8:2887-2896. [PMID: 36713701 PMCID: PMC9878621 DOI: 10.1021/acsomega.2c04414] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 12/26/2022] [Indexed: 06/18/2023]
Abstract
The overuse of antibiotics in aquaculture and pharmaceuticals and their subsequent leaking into the environment have been demonstrated to be a potential route for creating antibiotic resistance in bacteria. In order to assess the impact of this problem and take regulatory measures, it is necessary to develop tools that allow for the detection of antibiotics in environmental samples in a routine, low-cost manner. In this study, we integrated gold nanoparticles (AuNPs) into a molecularly imprinted polymer (MIP) membrane to fabricate a new sensor for the detection of norfloxacin in pharmaceuticals and aquaculture samples. The receptor layers were characterized by scanning electron microscopy, electrochemical impedance spectroscopy, and Raman spectroscopy. The results of these studies demonstrate that the addition of AuNPs to the polymer network enhanced the sensor sensitivity by at least a factor of two. The MIP-AuNPs sensor has a low detection limit (0.15 ng/mL, S/N = 3) with a wide linear range and very high sensitivity. The selectivity of the fabricated sensor was measured in the sample containing other antibiotics (like chloramphenicol, ciprofloxacin, and levofloxacin). Rapid and precise norfloxacin detection in pharmaceutical compounds and fishpond water samples indicates that the fabricated sensor has the potential to be used for routine screening of aquacultures and pharmaceutical processes.
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Affiliation(s)
- Oanh Thi Vu
- Vietnam-Korea
Institute of Science and Technology, Hoa Lac Hi-Tech Park, Research and Development Zone, Hanoi100000, Vietnam
| | - Quoc Hao Nguyen
- Department
of Chemical Engineering (Integrated Engineering), Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do17104, Republic of Korea
| | - Tin Nguy Phan
- Vietnam-Korea
Institute of Science and Technology, Hoa Lac Hi-Tech Park, Research and Development Zone, Hanoi100000, Vietnam
| | - Thanh ThuyThi Luong
- National
Institute of Occupational and Environmental Health, 57 Le Quy Don,
Hai Ba Trung District, Hanoi3800 016, Vietnam
| | - Kasper Eersels
- Sensor
Engineering Department, Faculty of Science and Engineering, Maastricht University, Maastricht6200 MD, The Netherlands
| | - Patrick Wagner
- Department
of Physics and Astronomy, Laboratory for Soft Matter and Biophysics, KU Leuven, Celestijnenlaan 200 D, LeuvenB-3001, Belgium
| | - Lien Thi Ngoc Truong
- Vietnam-Korea
Institute of Science and Technology, Hoa Lac Hi-Tech Park, Research and Development Zone, Hanoi100000, Vietnam
- School of
Engineering Physics, Hanoi University of
Science and Technology, No. 1 Dai Co Viet Road, Hai Ba Trung District, Hanoi100000, Vietnam
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7
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Tammiku-Taul J, Burk P. Nonempirical Prediction of the Relative Electrospray Ionization Efficiencies of Nitroanilines by Combined CBS-QB3 and SCC-DFTB Calculations. J Phys Chem A 2022; 126:8939-8944. [DOI: 10.1021/acs.jpca.2c05420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Jaana Tammiku-Taul
- Institute of Chemistry, University of Tartu, Ravila 14A, Tartu 50411, Estonia
| | - Peeter Burk
- Institute of Chemistry, University of Tartu, Ravila 14A, Tartu 50411, Estonia
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8
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Paglia G, Smith AJ, Astarita G. Ion mobility mass spectrometry in the omics era: Challenges and opportunities for metabolomics and lipidomics. MASS SPECTROMETRY REVIEWS 2022; 41:722-765. [PMID: 33522625 DOI: 10.1002/mas.21686] [Citation(s) in RCA: 90] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 01/17/2021] [Accepted: 01/17/2021] [Indexed: 06/12/2023]
Abstract
Researchers worldwide are taking advantage of novel, commercially available, technologies, such as ion mobility mass spectrometry (IM-MS), for metabolomics and lipidomics applications in a variety of fields including life, biomedical, and food sciences. IM-MS provides three main technical advantages over traditional LC-MS workflows. Firstly, in addition to mass, IM-MS allows collision cross-section values to be measured for metabolites and lipids, a physicochemical identifier related to the chemical shape of an analyte that increases the confidence of identification. Second, IM-MS increases peak capacity and the signal-to-noise, improving fingerprinting as well as quantification, and better defining the spatial localization of metabolites and lipids in biological and food samples. Third, IM-MS can be coupled with various fragmentation modes, adding new tools to improve structural characterization and molecular annotation. Here, we review the state-of-the-art in IM-MS technologies and approaches utilized to support metabolomics and lipidomics applications and we assess the challenges and opportunities in this growing field.
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Affiliation(s)
- Giuseppe Paglia
- School of Medicine and Surgery, University of Milano-Bicocca, Vedano al Lambro (MB), Italy
| | - Andrew J Smith
- School of Medicine and Surgery, University of Milano-Bicocca, Vedano al Lambro (MB), Italy
| | - Giuseppe Astarita
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, District of Columbia, USA
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9
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Delvaux A, Rathahao-Paris E, Alves S. Different ion mobility-mass spectrometry coupling techniques to promote metabolomics. MASS SPECTROMETRY REVIEWS 2022; 41:695-721. [PMID: 33492707 DOI: 10.1002/mas.21685] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Metabolomics has become increasingly popular in recent years for many applications ranging from clinical diagnosis, human health to biotechnological questioning. Despite technological advances, metabolomic studies are still currently limited by the difficulty of identifying all metabolites, a class of compounds with great chemical diversity. Although lengthy chromatographic analyses are often used to obtain comprehensive data, many isobar and isomer metabolites still remain unresolved, which is a critical point for the compound identification. Currently, ion mobility spectrometry is being explored in metabolomics as a way to improve metabolome coverage, analysis throughput and isomer separation. In this review, all the steps of a typical workflow for untargeted metabolomics are discussed considering the use of an ion mobility instrument. An overview of metabolomics is first presented followed by a brief description of ion mobility instrumentation. The ion mobility potential for complex mixture analysis is discussed regarding its coupling with a mass spectrometer alone, providing gas-phase separation before mass analysis as well as its combination with different separation platforms (conventional hyphenation but also multidimensional ion mobility couplings), offering multidimensional separation. Various instrumental and analytical conditions for improving the ion mobility separation are also described. Finally, data mining, including software packages and visualization approaches, as well as the construction of ion mobility databases for the metabolite identification are examined.
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Affiliation(s)
- Aurélie Delvaux
- Faculté des Sciences et de l'Ingénierie, Institut Parisien de Chimie Moléculaire (IPCM), Sorbonne Université, Paris, 75005, France
| | - Estelle Rathahao-Paris
- Faculté des Sciences et de l'Ingénierie, Institut Parisien de Chimie Moléculaire (IPCM), Sorbonne Université, Paris, 75005, France
- Département Médicaments et Technologies pour la Santé (DMTS), SPI, Université Paris-Saclay, CEA, INRAE, Gif-sur-Yvette, 91191, France
| | - Sandra Alves
- Faculté des Sciences et de l'Ingénierie, Institut Parisien de Chimie Moléculaire (IPCM), Sorbonne Université, Paris, 75005, France
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10
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Liu W, Chen Y, Yin X, Liu F, Li W, Yu J, Jing G, Li W. A Rapid and on-Site detection of Pesticide Residue from Fruit Samples based on Surface Swab-Electrospray Ionization-Ion Mobility Spectrometry. Microchem J 2022. [DOI: 10.1016/j.microc.2022.107919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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11
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Sepman H, Tshepelevitsh S, Hupatz H, Kruve A. Protomer Formation Can Aid the Structural Identification of Caffeine Metabolites. Anal Chem 2022; 94:10601-10609. [PMID: 35861491 PMCID: PMC9352149 DOI: 10.1021/acs.analchem.2c00257] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
![]()
The structural annotation of isomeric metabolites remains
a key
challenge in untargeted electrospray ionization/high-resolution mass
spectrometry (ESI/HRMS) metabolomic analysis. Many metabolites are
polyfunctional compounds that may form protomers in electrospray ionization
sources and therefore yield multiple peaks in ion mobility spectra.
Protomer formation is strongly structure-specific. Here, we explore
the possibility of using protomer formation for structural elucidation
in metabolomics on the example of caffeine, its eight metabolites,
and structurally related compounds. It is observed that two-thirds
of the studied compounds formed high- and low-mobility species in
high-resolution ion mobility. Structures in which proton hopping was
hindered by a methyl group at the purine ring nitrogen (position 3)
yielded structure-indicative fragments with collision-induced dissociation
(CID) for high- and low-mobility ions. For compounds where such a
methyl group was not present, a gas-phase equilibrium could be observed
for tautomeric species with two-dimensional ion mobility. We show
that the protomer formation and the gas-phase properties of the protomers
can be related to the structure of caffeine metabolites and facilitate
the identification of the structural isomers.
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Affiliation(s)
- Helen Sepman
- Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16, 106 91 Stockholm, Sweden
| | - Sofja Tshepelevitsh
- Institute of Chemistry, University of Tartu, Ravila 14a, Tartu 50411, Estonia
| | - Henrik Hupatz
- Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 20, 14195 Berlin, Germany
| | - Anneli Kruve
- Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16, 106 91 Stockholm, Sweden
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12
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McCann A, Kune C, Massonnet P, Far J, Ongena M, Eppe G, Quinton L, De Pauw E. Cyclic Peptide Protomer Detection in the Gas Phase: Impact on CCS Measurement and Fragmentation Patterns. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:851-858. [PMID: 35467879 DOI: 10.1021/jasms.2c00035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
With the recent improvements in ion mobility resolution, it is now possible to separate small protomeric tautomers, called protomers. In larger molecules above 1000 Da such as peptides, a few studies suggest that protomers do exist as well and may contribute to their gas-phase conformational heterogeneity. In this work, we observed a CCS distribution that can be explained by the presence of protomers of surfactin, a small lipopeptide with no basic site. Following preliminary density functional theoretical calculations, several protonation sites in the gas phase were energetically favorable in positive ionization mode. Experimentally, at least three near-resolved IM peaks were observed in positive ionization mode, while only one was detected in negative ionization mode. These results were in good agreement with the DFT predictions. CID breakdown curve analysis after IM separation showed different inflection points (CE50) suggesting that different intramolecular interactions were implied in the stabilization of the structures of surfactin. The fragment ratio observed after collision-induced fragmentation was also different, suggesting different ring-opening localizations. All these observations support the presence of protomers on the cyclic peptide moieties of the surfactin. These data strongly suggest that protomeric tautomerism can still be observed on molecules above 1000 Da if the IM resolving power is sufficient. It also supports that the proton localization involves a change in the 3D structure that can affect the experimental CCS and the fragmentation channels of such peptides.
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Affiliation(s)
- Andréa McCann
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
| | - Christopher Kune
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
| | - Philippe Massonnet
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
- Maastricht Multimodal Molecular Imaging (M4I) Institute, Division of Imaging Mass Spectrometry, 6229ER Maastricht, Limburg, The Netherlands
| | - Johann Far
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
| | - Marc Ongena
- Gembloux Agro-Bio Tech, University of Liege, 5030 Gembloux, Belgium
| | - Gauthier Eppe
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
| | - Loïc Quinton
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
| | - Edwin De Pauw
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, 4000 Liège, Belgium
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13
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Zhang L, Wang Y, Zheng F, Zhu D, Liang Y, Shi Q. Influence Exerted by the Solvent Effect on the Mobility Peak of 1,8-Naphthalic Anhydride in Ion Mobility Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:457-462. [PMID: 35089717 DOI: 10.1021/jasms.1c00299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The collision cross-section (CCS) values of ions determined by ion mobility-mass spectrometry (IM-MS) can be used to deduce the shape and size of the ions. For each compound, as well as its isomer or tautomer, a unique arrival time peak was obtained in extracted ion mobility (EIM) spectra, which corresponded to a specific CCS value. However, the generation of solvated ions by electrospray ionization (ESI) increases the number of mobility peaks, which makes the EIM spectra difficult to interpret. In this study, solvent clusters formed by acetonitrile and methanol around 1,8-naphthalic anhydride (1,8-NA) cations ([C12H6O3 + H]+1,8-NA) were investigated using trapped ion mobility spectrometry-time-of-flight mass spectrometry (TIMS-TOF MS). The effects of infusion flow rate, nebulizer gas pressure, drying gas rate, and drying gas temperature on the formation of solvent clusters from acetonitrile and methanolic solution were systematically studied. The formation of solvent clusters was observed with infusion flow rates increased, which was manifested by the larger experimental CCS values of [C12H6O3 + H]+1,8-NA. Acetonitrile tended to form solvent clusters around ions more readily than methanol. These solvent clusters were stable enough to be detected by TIMS, but they cannot survive under ion activation conditions of mass spectrometry (MS). Increasing the nebulizer gas pressure seems to be a better way to eliminate the formation of solvent clusters in TIMS-TOF MS and give a "cleaner" EIM spectra. The current research demonstrates that more attention should be paid to the solvent effect on CCS values and their interpretation.
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Affiliation(s)
- Lingzhi Zhang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, P.R. China
| | - Yinghao Wang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, P.R. China
| | - Fang Zheng
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, P.R. China
| | - Di Zhu
- College of Science, China University of Petroleum, Beijing 102249, P.R. China
| | - Yongmei Liang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, P.R. China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, P.R. China
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14
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Ucur B, Maccarone AT, Ellis SR, Blanksby SJ, Trevitt AJ. Solvent-Mediated Proton-Transfer Catalysis of the Gas-Phase Isomerization of Ciprofloxacin Protomers. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:347-354. [PMID: 35014802 DOI: 10.1021/jasms.1c00331] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Understanding how neutral molecules become protonated during positive-ion electrospray ionization (ESI) mass spectrometry is critically important to ensure analytes can be efficiently ionized, detected, and unambiguously identified. The ESI solvent is one of several parameters that can alter the dominant site of protonation in polyfunctional molecules and thus, in turn, can significantly change the collision-induced dissociation (CID) mass spectra relied upon for compound identification. Ciprofloxacin─a common fluoroquinolone antibiotic─is one such example whereby positive-ion ESI can result in gas-phase [M + H]+ ions protonated at either the keto-oxygen or the piperazine-nitrogen. Here, we demonstrate that these protonation isomers (or protomers) of ciprofloxacin can be resolved by differential ion mobility spectrometry and give rise to distinctive CID mass spectra following both charge-directed and charge-remote mechanisms. Interaction of mobility-selected protomers with methanol vapor (added via the throttle gas supply) was found to irreversibly convert the piperazine N-protomer to the keto-O-protomer. This methanol-mediated proton-transport catalysis is driven by the overall exothermicity of the reaction, which is computed to favor the O-protomer by 93 kJ mol-1 (in the gas phase). Conversely, gas phase interactions of mobility-selected ions with acetonitrile vapor selectively depletes the N-protomer ion signal as formation of stable [M + H + CH3CN]+ cluster ions skews the apparent protomer population ratio, as the O-protomer is unaffected. These findings provide a mechanistic basis for tuning protomer populations to ensure faithful characterization of multifunctional molecules by tandem mass spectrometry.
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Affiliation(s)
- Boris Ucur
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Alan T Maccarone
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Shane R Ellis
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Stephen J Blanksby
- Central Analytical Research Facility and School of Chemistry and Physics, Queensland University of Technology, Brisbane 4001, Australia
| | - Adam J Trevitt
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
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15
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Gandhi VD, Larriba-Andaluz C. Predicting ion mobility as a function of the electric field for small ions in light gases. Anal Chim Acta 2021; 1184:339019. [PMID: 34625252 DOI: 10.1016/j.aca.2021.339019] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 08/07/2021] [Accepted: 08/30/2021] [Indexed: 12/01/2022]
Abstract
High resolution mobility devices such as Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) and Differential Mobility spectrometers (DMS) use strong electric fields to gas concentration ratios, E/N, to separate ions in the gas phase. While extremely successful, their empirical results show a non-linear, ion-dependent relation between mobility K and E/N that is difficult to characterize. The one-temperature theory Mason-Schamp equation, which is the most widely used ion mobility equation, unfortunately, cannot capture this behavior. When the two-temperature theory is used, it can be shown that the K-E/N behavior can be followed quite closely numerically by equating the effect of increasing the field to an increase in the ion temperature. This is attempted here for small ions in a Helium gas environment showing good agreement over the whole field range. To improve the numerical characterization, the Lennard-Jones (L-J) potentials may be optimized. This is attempted for Carbon, Hydrogen, Oxygen and Nitrogen at different degrees of theory up to the fourth approximation, which is assumed to be exact. The optimization of L-J improves the accuracy yielding errors of about 3% on average. The fact that a constant set of L-J potentials work for the whole range of E/N and for several molecules, also suggests that inelastic collisions can be circumvented in calculations for He. The peculiar K-E/N hump behaviors are studied, and whether mobility increases or decreases with E/N is shown to derive from a competition between relative kinetic energy and the interaction potentials.
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Affiliation(s)
- Viraj D Gandhi
- Mechanical Engineering, Purdue University, 610 Purdue Mall, West Lafayette, 47907, Indiana, United States; Mechanical Engineering, Indiana University Purdue University - Indianapolis, 723 W Michigan Street, Indianapolis, 46202, Indiana, United States
| | - Carlos Larriba-Andaluz
- Mechanical Engineering, Indiana University Purdue University - Indianapolis, 723 W Michigan Street, Indianapolis, 46202, Indiana, United States.
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16
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Coughlan NJA, Fu W, Guna M, Schneider BB, Le Blanc JCY, Campbell JL, Hopkins WS. Electronic spectroscopy of differential mobility-selected prototropic isomers of protonated para-aminobenzoic acid. Phys Chem Chem Phys 2021; 23:20607-20614. [PMID: 34505849 DOI: 10.1039/d1cp02120f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
para-Aminobenzoic acid (PABA) was electrosprayed from mixtures of protic and aprotic solvents, leading to formation of two prototropic isomers in the gas phase whose relative populations depended on the composition of the electrospray solvent. The two ion populations were separated in the gas phase using differential mobility spectrometry (DMS) within a nitrogen-only environment at atmospheric pressure. Under high-field conditions, the two prototropic isomers eluted with baseline signal separation with the N-protonated isomer having a more negative CV shift than the O-protonated isomer, in accord with previous DMS studies. The conditions most favorable for formation and separation of each tautomer were used to trap each prototropic isomer in a quadrupole ion trap for photodissociation action spectroscopy experiments. Spectral interrogation of each prototropic isomer in the UV region (3-6 eV) showed good agreement with previously recorded spectra, although a previously reported band (4.8-5.4 eV) was less intense for the O-protonated isomer in our measured spectrum. Without DMS selection, the measured spectra contained features corresponding to both protonated isomers even when solvent conditions were optimised for formation of a single isomer. Interconversion between protonated isomers within the ion trap was observed when protic ESI solvents were employed, leading to spectral cross contamination even with mobility selection. CCSD vertical excitation energies and vertical gradient (VG) Franck-Condon simulations are presented and reproduce the measured spectral features with near-quantitative agreement, providing supporting evidence for spectral assignments.
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Affiliation(s)
- Neville J A Coughlan
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. .,Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Weiqiang Fu
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. .,Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Mircea Guna
- SCIEX, Four Valley Drive, Concord, Ontario, L4K 4V8, Canada
| | | | | | - J Larry Campbell
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. .,Bedrock Scientific Inc., Milton, Ontario, Canada.,WaterMine Innovation, Waterloo, Ontario, Canada
| | - W Scott Hopkins
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. .,Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.,WaterMine Innovation, Waterloo, Ontario, Canada.,Centre for Eye and Vision Research, Hong Kong Science Park, New Territories, Hong Kong
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17
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Schrader RL, Marsh BM, Cooks RG. Atmospheric Pressure Drift Tube Ion Mobility Spectrometry Coupled with Two-Dimensional Tandem Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:2105-2109. [PMID: 34232037 DOI: 10.1021/jasms.1c00180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Atmospheric pressure drift tube ion mobility was coupled with two-dimensional tandem mass spectrometry (2D MS/MS) in a linear ion trap to simultaneously collect ion mobility and the entire MS/MS data domain. Utilizing ion intensities from precursor ion and neutral loss scan lines, ion mobility spectra of multiple compounds with particular functional groups were acquired in a single experiment. Functional group-specific ion mobility spectra were demonstrated for a standard mixture of lipids. Additionally, ion mobility was used to separate isobaric ions prior to 2D MS/MS. The combination of these two methods offers improvements for the analysis of complex mixtures.
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Affiliation(s)
- Robert L Schrader
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Brett M Marsh
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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18
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McCullagh M, Goscinny S, Palmer M, Ujma J. Investigations into pesticide charge site isomers using conventional IM and cIM systems. Talanta 2021; 234:122604. [PMID: 34364418 DOI: 10.1016/j.talanta.2021.122604] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 06/05/2021] [Accepted: 06/09/2021] [Indexed: 11/28/2022]
Abstract
A growing number of pesticides are being used around the world necessitating strict regulatory policies to guarantee consumer safety. Liquid Chromatography - Mass Spectrometry (LC-MS) is a highly sensitive method for pesticide screening, which provides retention time, mass/charge ratios and the relative abundances of characteristic product ions. Variability in the latter necessitates relatively large tolerances (±30%, SANCO/12682/2019, current EU regulation). One cause of this variability may stem from the presence of different charge-site isomers (charge carrier being a proton, sodium cation, potassium cation and alike); each yielding a set of different product ions, of which the relative ratios are influenced by solution and ion source conditions. Consequently, varying relative abundances may be observed for analyte ions produced from calibration standards, chemical residues in food matrices and across different instruments. Ion Mobility Spectrometry (IMS) is a fast, gas phase separation technique which can resolve charge-site isomers based on differences in their collisional cross sections (CCSs). We previously used the IM device embedded in LC-IM-MS geometry to generate a pesticide CCS database and subsequently focussed upon identification of pesticides which form charge-site isomers. Latterly, we applied this approach to screen food commodities for pesticide residues. In some instances, isomer separation was clear, however sometimes broad, unresolved distributions were observed. Using a high-resolution cyclic IM device (cIM) we resolved and determined CCS values of species of indoxacarb, spinosad, fenpyroximate, epoxiconazole, metaflumizone and avermectin. Furthermore, utilising novel cIM functionalities (tandem-IM) we discovered that two spinosyn sodimers can interconvert in the gas phase.
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Affiliation(s)
| | - Séverine Goscinny
- Scientific Institute of Public Health, 14, Rue Juliette Wytsman, 1050, Brussels, Belgium
| | - Martin Palmer
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, UK
| | - Jakub Ujma
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, UK
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19
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Borges R, Colby SM, Das S, Edison AS, Fiehn O, Kind T, Lee J, Merrill AT, Merz KM, Metz TO, Nunez JR, Tantillo DJ, Wang LP, Wang S, Renslow RS. Quantum Chemistry Calculations for Metabolomics. Chem Rev 2021; 121:5633-5670. [PMID: 33979149 PMCID: PMC8161423 DOI: 10.1021/acs.chemrev.0c00901] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Indexed: 02/07/2023]
Abstract
A primary goal of metabolomics studies is to fully characterize the small-molecule composition of complex biological and environmental samples. However, despite advances in analytical technologies over the past two decades, the majority of small molecules in complex samples are not readily identifiable due to the immense structural and chemical diversity present within the metabolome. Current gold-standard identification methods rely on reference libraries built using authentic chemical materials ("standards"), which are not available for most molecules. Computational quantum chemistry methods, which can be used to calculate chemical properties that are then measured by analytical platforms, offer an alternative route for building reference libraries, i.e., in silico libraries for "standards-free" identification. In this review, we cover the major roadblocks currently facing metabolomics and discuss applications where quantum chemistry calculations offer a solution. Several successful examples for nuclear magnetic resonance spectroscopy, ion mobility spectrometry, infrared spectroscopy, and mass spectrometry methods are reviewed. Finally, we consider current best practices, sources of error, and provide an outlook for quantum chemistry calculations in metabolomics studies. We expect this review will inspire researchers in the field of small-molecule identification to accelerate adoption of in silico methods for generation of reference libraries and to add quantum chemistry calculations as another tool at their disposal to characterize complex samples.
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Affiliation(s)
- Ricardo
M. Borges
- Walter
Mors Institute of Research on Natural Products, Federal University of Rio de Janeiro, Rio de Janeiro 21941-901, Brazil
| | - Sean M. Colby
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
| | - Susanta Das
- Department
of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Arthur S. Edison
- Departments
of Genetics and Biochemistry and Molecular Biology, Complex Carbohydrate
Research Center and Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602, United States
| | - Oliver Fiehn
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
| | - Tobias Kind
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
| | - Jesi Lee
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Amy T. Merrill
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Kenneth M. Merz
- Department
of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Thomas O. Metz
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
| | - Jamie R. Nunez
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
| | - Dean J. Tantillo
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Lee-Ping Wang
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Shunyang Wang
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Ryan S. Renslow
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
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20
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Ross DH, Xu L. Determination of drugs and drug metabolites by ion mobility-mass spectrometry: A review. Anal Chim Acta 2021; 1154:338270. [PMID: 33736803 DOI: 10.1016/j.aca.2021.338270] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/25/2021] [Accepted: 01/27/2021] [Indexed: 01/04/2023]
Abstract
Ion mobility-mass spectrometry (IM-MS) has gained increased applications in the characterization and identification of drugs and drug metabolites, largely owning to the complementary separation of analyte ions based on their gas-phase size and shape in the IM dimension in addition to their mass-to-charge ratios. In this review, we discuss recent advances in such applications. We first introduce various types of IM techniques, focusing on those that allow the measurement of collision cross section (CCS), the physical property of an ion that reflects its gas-phase size and shape. Next, we discuss the IM-MS landscape of the large chemical space of drugs and multimodal distributions of certain drugs in IM separation due to the presence of protomers. We then review drug metabolism reactions and discuss the application of IM-MS in separation and identification of isomeric drug metabolites. Subsequently, we discuss various approaches to generate theoretical and predicted CCS data, including theory-based calculation methods and data-driven prediction models, and currently available resources on these approaches. Finally, current limitations and future directions of application of IM-MS are discussed.
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Affiliation(s)
- Dylan H Ross
- Department of Medicinal Chemistry, University of Washington, 1959, NE Pacific Street, HSB H-172, Seattle, WA, USA
| | - Libin Xu
- Department of Medicinal Chemistry, University of Washington, 1959, NE Pacific Street, HSB H-172, Seattle, WA, USA.
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21
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Ross DH, Seguin RP, Xu L. Characterization of the Impact of Drug Metabolism on the Gas-Phase Structures of Drugs Using Ion Mobility-Mass Spectrometry. Anal Chem 2019; 91:14498-14507. [PMID: 31613088 DOI: 10.1021/acs.analchem.9b03292] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Conventional strategies for drug metabolite identification employ a combination of liquid chromatography-mass spectrometry (LC-MS), which offers higher throughput but provides limited structural information, and nuclear magnetic resonance spectroscopy, which can achieves the most definitive identification but lacks throughput. Ion mobility-mass spectrometry (IM-MS) is a rapid, two-dimensional analysis that separates ions on the basis of their gas-phase size and shape (reflected by collision cross section, CCS) and their mass-to-charge (m/z) ratios. The rapid nature of IM separation combined with the structural information provided by CCS make IM-MS a promising technique for obtaining more structural information on drug metabolites without sacrificing analytical throughput. Here, we present an in vitro biosynthesis coupled with IM-MS strategy for rapid generation and analysis of drug metabolites. Drug metabolites were generated in vitro using pooled subcellular fractions derived from human liver and analyzed using a rapid flow injection-IM-MS method. We measured CCS values for 19 parent drugs and their 37 metabolites generated in vitro (78 values in total), representing a wide variety of metabolic modifications. Post-IM fragmentation and computational modeling were used to support metabolite identifications and explore the structural characteristics driving behaviors observed in IM separation. Overall, we found the effects of metabolic modifications on the gas-phase structures of the metabolites to be highly dependent upon the structural characteristics of the parent compounds and the specific position of the modification. This in vitro biosynthesis coupled with rapid IM-MS analysis workflow represents a promising platform for rapid and high-confidence identification of drug metabolites, applicable at a large scale.
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Affiliation(s)
- Dylan H Ross
- Department of Medicinal Chemistry , University of Washington , Seattle , Washington 98195 , United States
| | - Ryan P Seguin
- Department of Medicinal Chemistry , University of Washington , Seattle , Washington 98195 , United States
| | - Libin Xu
- Department of Medicinal Chemistry , University of Washington , Seattle , Washington 98195 , United States
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22
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McCullagh M, Giles K, Richardson K, Stead S, Palmer M. Investigations into the performance of travelling wave enabled conventional and cyclic ion mobility systems to characterise protomers of fluoroquinolone antibiotic residues. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33 Suppl 2:11-21. [PMID: 30549457 DOI: 10.1002/rcm.8371] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 12/08/2018] [Accepted: 12/10/2018] [Indexed: 05/26/2023]
Abstract
RATIONALE Fluoroquinolones (FLQs) have been shown to form protomers with distinctive fragment profiles. Experimental parameters affect protomer formation, impacting observed conventional tandem mass spectrometric (MS/MS) dissociation and multiple reaction monitoring (MRM) transition reproducibility. Collision cross section (CCS) measurement can provide an additional identification metric and improved ion mobility (IM) separation strategies could provide further understanding of fluctuations in fragmentation when using electrospray ionisation (ESI). METHODS Porcine muscle tissue was fortified with nine fluoroquinolone antibiotics. Extracts were cleaned using QuEChERS dispersive extraction. Separation was achieved via ultra-high-performance liquid chromatography (UHPLC) and analysis performed using positive ion ESI coupled with linear T-wave IM (N2 and CO2 drift gas) and cyclic IM-MS (calibrated to perform accurate mass and CCS measurement). RESULTS IM-resolved protomeric species have been observed for nine FLQs (uniquely three for danofloxacin). Long-term reproducibility and cross-platform T-wave/cIM studies have demonstrated CCS metric errors <1.5% when compared with a FLQ protomer reference CCS library. When comparing FLQ protomer separation using a standard, linear T-wave IM separator (N2 /CO2 ) and using a high-resolution cyclic T-wave device (N2 ), protomer peak-to-peak resolution ranged between Rs = 1 to Rs = 6 for the IM strategies utilised. CONCLUSIONS CCS is a reliable cross platform metric; specific FLQ CCS identification fingerprints have been produced, illustrating the potential to compliment MS/MS specificity or provide an alternative identification metric. Using cIM there is opportunity to correlate the erratic nature of protomer formation with the analytical conditions used and to gain further understanding of ionisation/dissociation mechanisms taking place during routine analyses.
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Affiliation(s)
- Michael McCullagh
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, SK9 4AX, UK
| | - Kevin Giles
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, SK9 4AX, UK
| | - Keith Richardson
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, SK9 4AX, UK
| | - Sara Stead
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, SK9 4AX, UK
| | - Martin Palmer
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, SK9 4AX, UK
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23
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Schorr P, Volmer DA. Using differential ion mobility spectrometry to perform class-specific ion-molecule reactions of 4-quinolones with selected chemical reagents. Anal Bioanal Chem 2019; 411:6247-6253. [PMID: 30972473 DOI: 10.1007/s00216-019-01789-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/12/2019] [Accepted: 03/18/2019] [Indexed: 11/26/2022]
Abstract
Gas phase ion/molecule reactions are often used in analytical applications to support the analysis of isomers or to identify specific functional groups of organic molecules. Until now, deliberate chemical reactions have not been performed in differential ion mobility spectrometry (DMS) devices except for hydrogen exchange and cluster formation. The present work extends that of Colorado and Brodbelt (Anal Chem 66:2330-5, 1994) on ion/molecule reactions in an ion trap mass spectrometer. In this study, class-specific chemical reactions of 4-quinolone antibiotics with various chemical reagents were used to demonstrate the analytical utility of ion/molecule reactions in a DMS drift cell. For these reactions, dehydrated reactive precursor ions were initially formed and made to undergo annulation reactions with selected reagents within the timescale of the DMS separation. Careful study of the energies required for dissociation of the adducts confirmed the covalent nature of the newly formed bond; thus demonstrating the analytical utility of this approach. Graphical abstract.
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Affiliation(s)
- Pascal Schorr
- Bioanalytical Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Dietrich A Volmer
- Bioanalytical Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany.
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24
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Marlton SJP, McKinnon BI, Ucur B, Maccarone AT, Donald WA, Blanksby SJ, Trevitt AJ. Selecting and identifying gas-phase protonation isomers of nicotineH+ using combined laser, ion mobility and mass spectrometry techniques. Faraday Discuss 2019; 217:453-475. [DOI: 10.1039/c8fd00212f] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Protonation isomers of gas-phase nicotineH+ are separated and assigned using a combination of FAIMS and UV photodissociation action spectroscopy.
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Affiliation(s)
| | | | - Boris Ucur
- School of Chemistry
- University of Wollongong
- Wollongong
- Australia
| | | | | | - Stephen J. Blanksby
- Central Analytical Research Facility
- Institute for Future Environments
- Queensland University of Technology
- Brisbane
- Australia
| | - Adam J. Trevitt
- School of Chemistry
- University of Wollongong
- Wollongong
- Australia
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25
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Lim D, Davidson KL, Son S, Ahmed A, Bush MF, Kim S. Determining Collision Cross‐Sections of Aromatic Compounds in Crude Oil by Using Aromatic Compound Mixture as Calibration Standard. B KOREAN CHEM SOC 2018. [DOI: 10.1002/bkcs.11653] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Dongwan Lim
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
| | | | - Seungwoo Son
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
| | - Arif Ahmed
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
| | - Matthew F. Bush
- Department of ChemistryUniversity of Washington Seattle WA, 98195‐1700 USA
| | - Sunghwan Kim
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
- Green‐Nano Materials Research Center Daegu 41566 Republic of Korea
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26
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Tejada-Casado C, Hernández-Mesa M, Monteau F, Lara FJ, Olmo-Iruela MD, García-Campaña AM, Le Bizec B, Dervilly-Pinel G. Collision cross section (CCS) as a complementary parameter to characterize human and veterinary drugs. Anal Chim Acta 2018; 1043:52-63. [DOI: 10.1016/j.aca.2018.09.065] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 09/20/2018] [Accepted: 09/26/2018] [Indexed: 12/27/2022]
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27
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Hinnenkamp V, Klein J, Meckelmann SW, Balsaa P, Schmidt TC, Schmitz OJ. Comparison of CCS Values Determined by Traveling Wave Ion Mobility Mass Spectrometry and Drift Tube Ion Mobility Mass Spectrometry. Anal Chem 2018; 90:12042-12050. [DOI: 10.1021/acs.analchem.8b02711] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Vanessa Hinnenkamp
- IWW Water Centre, Moritzstraße 26, 45476 Muelheim an der Ruhr, Germany
- Instrumental Analytical Chemistry and Centre for Water and Environmental Research, Universitaetsstrasse 5, 45141 Essen, Germany
| | | | | | - Peter Balsaa
- IWW Water Centre, Moritzstraße 26, 45476 Muelheim an der Ruhr, Germany
| | - Torsten C. Schmidt
- IWW Water Centre, Moritzstraße 26, 45476 Muelheim an der Ruhr, Germany
- Instrumental Analytical Chemistry and Centre for Water and Environmental Research, Universitaetsstrasse 5, 45141 Essen, Germany
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28
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Blaženović I, Kind T, Ji J, Fiehn O. Software Tools and Approaches for Compound Identification of LC-MS/MS Data in Metabolomics. Metabolites 2018; 8:E31. [PMID: 29748461 PMCID: PMC6027441 DOI: 10.3390/metabo8020031] [Citation(s) in RCA: 402] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 04/26/2018] [Accepted: 05/06/2018] [Indexed: 01/17/2023] Open
Abstract
The annotation of small molecules remains a major challenge in untargeted mass spectrometry-based metabolomics. We here critically discuss structured elucidation approaches and software that are designed to help during the annotation of unknown compounds. Only by elucidating unknown metabolites first is it possible to biologically interpret complex systems, to map compounds to pathways and to create reliable predictive metabolic models for translational and clinical research. These strategies include the construction and quality of tandem mass spectral databases such as the coalition of MassBank repositories and investigations of MS/MS matching confidence. We present in silico fragmentation tools such as MS-FINDER, CFM-ID, MetFrag, ChemDistiller and CSI:FingerID that can annotate compounds from existing structure databases and that have been used in the CASMI (critical assessment of small molecule identification) contests. Furthermore, the use of retention time models from liquid chromatography and the utility of collision cross-section modelling from ion mobility experiments are covered. Workflows and published examples of successfully annotated unknown compounds are included.
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Affiliation(s)
- Ivana Blaženović
- NIH West Coast Metabolomics Center, UC Davis Genome Center, University of California, Davis, CA 95616, USA.
| | - Tobias Kind
- NIH West Coast Metabolomics Center, UC Davis Genome Center, University of California, Davis, CA 95616, USA.
| | - Jian Ji
- State Key Laboratory of Food Science and Technology, School of Food Science of Jiangnan University, School of Food Science Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China.
| | - Oliver Fiehn
- NIH West Coast Metabolomics Center, UC Davis Genome Center, University of California, Davis, CA 95616, USA.
- Department of Biochemistry, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
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29
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Mehmood A, Janesko BG. Predicting ion mobility collision cross sections directly from standard quantum chemistry software. JOURNAL OF MASS SPECTROMETRY : JMS 2018; 53:432-434. [PMID: 29505693 DOI: 10.1002/jms.4078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/23/2018] [Accepted: 02/26/2018] [Indexed: 06/08/2023]
Abstract
A method is proposed to predict ions' collision cross-sectional area from properties that are already evaluated in standard quantum chemistry software. Computed molecular isodensity surface areas recover the predictions of existing projection approximations. Computed solvent cavity areas give comparable accuracy. This provides a simplified workflow for assigning ion-mobility mass spectra.
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Affiliation(s)
- Arshad Mehmood
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, TX, 76129, USA
| | - Benjamin G Janesko
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, TX, 76129, USA
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30
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Xia H, Attygalle AB. Transformation of the gas-phase favored O-protomer of p-aminobenzoic acid to its unfavored N-protomer by ion activation in the presence of water vapor: An ion-mobility mass spectrometry study. JOURNAL OF MASS SPECTROMETRY : JMS 2018; 53:353-360. [PMID: 29377420 DOI: 10.1002/jms.4066] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 01/12/2018] [Accepted: 01/18/2018] [Indexed: 05/26/2023]
Abstract
An ion-mobility mass spectrometry study showed that the preferred O-protonated form of p-aminobenzoic in the gas phase can be converted to the thermodynamically less favored N-protomer by in-source collision-induced ion activation during the ion transfer process from the atmospheric region to the first vacuum region if the humidity is high in the ion source. Upon the addition of water vapor to the nitrogen gas used to promote the solid analyte to the gas phase under helium-plasma ionization conditions, the intensity of the ion-mobility arrival-time peak for the N-protomer increased dramatically. Evidently, the ion-activation process in the first vacuum region is able to provide the energy required to surmount the barrier to isomerize the O-protomer to the more energetic N-protomer. The transfer of the proton attached to the carbonyl oxygen atom of the O-protomer to the amino group takes place by a water-bridge mechanism. Apparently, the postionization transformations that take place during the transmission of ions from the atmospheric-pressure ion source to the detector, via different physical compartments of low to high vacuum, play an eminent role in determining the population ratios eventually manifested at the detector.
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Affiliation(s)
- Hanxue Xia
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey, 07030, USA
| | - Athula B Attygalle
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey, 07030, USA
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31
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Hernández-Mesa M, Le Bizec B, Monteau F, García-Campaña AM, Dervilly-Pinel G. Collision Cross Section (CCS) Database: An Additional Measure to Characterize Steroids. Anal Chem 2018. [DOI: 10.1021/acs.analchem.7b05117] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Maykel Hernández-Mesa
- Laboratoire d’Etude
des Résidus et Contaminants dans les Aliments (LABERCA), INRA
UMR 1329, LUNAM Université, Oniris, Nantes F-44307, France
| | - Bruno Le Bizec
- Laboratoire d’Etude
des Résidus et Contaminants dans les Aliments (LABERCA), INRA
UMR 1329, LUNAM Université, Oniris, Nantes F-44307, France
| | - Fabrice Monteau
- Laboratoire d’Etude
des Résidus et Contaminants dans les Aliments (LABERCA), INRA
UMR 1329, LUNAM Université, Oniris, Nantes F-44307, France
| | - Ana M. García-Campaña
- Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Av. Fuentenueva s/n, Granada E-18071, Spain
| | - Gaud Dervilly-Pinel
- Laboratoire d’Etude
des Résidus et Contaminants dans les Aliments (LABERCA), INRA
UMR 1329, LUNAM Université, Oniris, Nantes F-44307, France
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32
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Zanotto L, Heerdt G, Souza PCT, Araujo G, Skaf MS. High performance collision cross section calculation-HPCCS. J Comput Chem 2018; 39:1675-1681. [PMID: 29498071 DOI: 10.1002/jcc.25199] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/31/2018] [Accepted: 02/07/2018] [Indexed: 12/13/2022]
Abstract
Since the commercial introduction of Ion Mobility coupled with Mass Spectrometry (IM-MS) devices in 2003, a large number of research laboratories have embraced the technique. IM-MS is a fairly rapid experiment used as a molecular separation tool and to obtain structural information. The interpretation of IM-MS data is still challenging and relies heavily on theoretical calculations of the molecule's collision cross section (CCS) against a buffer gas. Here, a new software (HPCCS) is presented, which performs CCS calculations using high perfomance computing techniques. Based on the trajectory method, HPCCS can accurately calculate CCS for a great variety of molecules, ranging from small organic molecules to large protein complexes, using helium or nitrogen as buffer gas with considerable gains in computer time compared to publicly available codes under the same level of theory. HPCCS is available as free software under the Academic Use License at https://github.com/cepid-cces/hpccs. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Leandro Zanotto
- Institute of Chemistry and Center for Computational Engineering & Sciences, University of Campinas, Campinas, São Paulo, 13083-852, Brazil
| | - Gabriel Heerdt
- Institute of Chemistry and Center for Computational Engineering & Sciences, University of Campinas, Campinas, São Paulo, 13083-852, Brazil
| | - Paulo C T Souza
- Institute of Chemistry and Center for Computational Engineering & Sciences, University of Campinas, Campinas, São Paulo, 13083-852, Brazil.,Faculty of Mathematics and Natural Sciences, University of Groningen, Groningen, 9747, AG, The Netherlands
| | - Guido Araujo
- Institute of Computing and Center for Computational Engineering & Sciences, University of Campinas, Campinas, São Paulo, 13083-970, Brazil
| | - Munir S Skaf
- Institute of Chemistry and Center for Computational Engineering & Sciences, University of Campinas, Campinas, São Paulo, 13083-852, Brazil
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33
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Wu T, Derrick J, Nahin M, Chen X, Larriba-Andaluz C. Optimization of long range potential interaction parameters in ion mobility spectrometry. J Chem Phys 2018; 148:074102. [DOI: 10.1063/1.5016170] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Tianyang Wu
- Mechanical Engineering, Indiana University-Purdue University Indianapolis, 723 W Michigan St., Indianapolis, Indiana 46202, USA
| | - Joseph Derrick
- Mechanical Engineering, Indiana University-Purdue University Indianapolis, 723 W Michigan St., Indianapolis, Indiana 46202, USA
| | - Minal Nahin
- Mechanical Engineering, Indiana University-Purdue University Indianapolis, 723 W Michigan St., Indianapolis, Indiana 46202, USA
| | - Xi Chen
- Mechanical Engineering, Indiana University-Purdue University Indianapolis, 723 W Michigan St., Indianapolis, Indiana 46202, USA
- Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907, USA
| | - Carlos Larriba-Andaluz
- Mechanical Engineering, Indiana University-Purdue University Indianapolis, 723 W Michigan St., Indianapolis, Indiana 46202, USA
- Integrated Nanosystems Development Institute (INDI), 420 University Blvd., Indianapolis, Indiana 46202, USA
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34
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Seo J, Warnke S, Gewinner S, Schöllkopf W, Bowers MT, Pagel K, von Helden G. The impact of environment and resonance effects on the site of protonation of aminobenzoic acid derivatives. Phys Chem Chem Phys 2018; 18:25474-25482. [PMID: 27722299 DOI: 10.1039/c6cp04941a] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The charge distribution in a molecule is crucial in determining its physical and chemical properties. Aminobenzoic acid derivatives are biologically active small molecules, which have two possible protonation sites: the amine (N-protonation) and the carbonyl oxygen (O-protonation). Here, we employ gas-phase infrared spectroscopy in combination with ion mobility-mass spectrometry and density functional theory calculations to unambiguously determine the preferred protonation sites of p-, m-, and o-isomers of aminobenzoic acids as well as their ethyl esters. The results show that the site of protonation does not only depend on the intrinsic molecular properties such as resonance effects, but also critically on the environment of the molecules. In an aqueous environment, N-protonation is expected to be lowest in energy for all species investigated here. In the gas phase, O-protonation can be preferred, and in those cases, both N- and O-protonated species are observed. To shed light on a possible proton migration pathway, the protonated molecule-solvent complex as well as proton-bound dimers are investigated.
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Affiliation(s)
- Jongcheol Seo
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Stephan Warnke
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Sandy Gewinner
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Wieland Schöllkopf
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Michael T Bowers
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | - Kevin Pagel
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany. and Freie Universität Berlin, Department of Biology, Chemistry and Pharmacy, Takustrasse 3, 14195 Berlin, Germany.
| | - Gert von Helden
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
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35
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Xia H, Attygalle AB. Untrapping Kinetically Trapped Ions: The Role of Water Vapor and Ion-Source Activation Conditions on the Gas-Phase Protomer Ratio of Benzocaine Revealed by Ion-Mobility Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:2580-2587. [PMID: 28936768 DOI: 10.1007/s13361-017-1806-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 08/25/2017] [Accepted: 08/30/2017] [Indexed: 06/07/2023]
Abstract
The role of water vapor in transforming the thermodynamically preferred species of protonated benzocaine to the less favored protomer was investigated using helium-plasma ionization (HePI) in conjunction with ion-mobility mass spectrometry (IM-MS). The IM arrival-time distribution (ATD) recorded from a neat benzocaine sample desorbed to the gas phase by a stream of dry nitrogen and ionized by HePI showed essentially one peak for the O-protonated species. However, when water vapor was introduced to the enclosed ion source, within a span of about 150 ms the ATD profile changed completely to one dominated by the N-protonated species. Under spray-based ionization conditions, the nature and composition of the solvents have been postulated to play a decisive role in defining the manifested protomer ratios. In reality, the solvent vapors present in the ion source (particularly the ambient humidity) indirectly dictate the gas-phase ratio of the protomers. Evidently, the gas-phase protomer ratio established at the confinement of the ions is readjusted by the ion-activation that takes place during the transmission of ions to the vacuum. Although it has been repeatedly stated that ions can retain a "memory" of their solution structures because they can be kinetically trapped, and thereby represent their solution-based stabilities, we show that the initial airborne ions can undergo significant transformations in the transit through the intermediate vacuum zones between the ion source and the mass detector. In this context, we demonstrate that the kinetically trapped N-protomer of benzocaine can be untrapped by reducing the humidity of the enclosed ion source. Graphical Abstract ᅟ.
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Affiliation(s)
- Hanxue Xia
- Center for Mass Spectrometry, Department of Biomedical Engineering, Chemistry, and Biological Sciences, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Athula B Attygalle
- Center for Mass Spectrometry, Department of Biomedical Engineering, Chemistry, and Biological Sciences, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.
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36
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Pracht P, Bauer CA, Grimme S. Automated and efficient quantum chemical determination and energetic ranking of molecular protonation sites. J Comput Chem 2017; 38:2618-2631. [DOI: 10.1002/jcc.24922] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/27/2017] [Accepted: 08/01/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Philipp Pracht
- Mulliken Center for Theoretical Chemistry, Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4; 53115 Bonn Germany
| | - Christoph Alexander Bauer
- Mulliken Center for Theoretical Chemistry, Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4; 53115 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4; 53115 Bonn Germany
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37
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Hines KM, Ross DH, Davidson KL, Bush MF, Xu L. Large-Scale Structural Characterization of Drug and Drug-Like Compounds by High-Throughput Ion Mobility-Mass Spectrometry. Anal Chem 2017; 89:9023-9030. [PMID: 28764324 PMCID: PMC5616088 DOI: 10.1021/acs.analchem.7b01709] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
![]()
Ion mobility-mass spectrometry (IM-MS)
can provide orthogonal information,
i.e., m/z and collision cross section
(CCS), for the identification of drugs and drug metabolites. However,
only a small number of CCS values are available for drugs, which limits
the use of CCS as an identification parameter and the assessment of
structure–function relationships of drugs using IM-MS. Here,
we report the development of a rapid workflow for the measurement
of CCS values of a large number of drug or drug-like molecules in
nitrogen on the widely available traveling wave IM-MS (TWIM-MS) platform.
Using a combination of small molecule and polypeptide CCS calibrants,
we successfully determined the nitrogen CCS values of 1425 drug or
drug-like molecules in the MicroSource Discovery Systems’ Spectrum
Collection using flow injection analysis of 384-well plates. Software
was developed to streamline data extraction, processing, and calibration.
We found that the overall drug collection covers a wide CCS range
for the same mass, suggesting a large structural diversity of these
drugs. However, individual drug classes appear to occupy a narrow
and unique space in the CCS–mass 2D spectrum, suggesting a
tight structure–function relationship for each class of drugs
with a specific target. We observed bimodal distributions for several
antibiotic species due to multiple protomers, including the known
fluoroquinolone protomers and the new finding of cephalosporin protomers.
Lastly, we demonstrated the utility of the high-throughput method
and drug CCS database by quickly and confidently confirming the active
component in a pharmaceutical product.
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Affiliation(s)
- Kelly M Hines
- Department of Medicinal Chemistry, ‡Department of Chemistry, University of Washington , Seattle, Washington 98195, United States
| | - Dylan H Ross
- Department of Medicinal Chemistry, ‡Department of Chemistry, University of Washington , Seattle, Washington 98195, United States
| | - Kimberly L Davidson
- Department of Medicinal Chemistry, ‡Department of Chemistry, University of Washington , Seattle, Washington 98195, United States
| | - Matthew F Bush
- Department of Medicinal Chemistry, ‡Department of Chemistry, University of Washington , Seattle, Washington 98195, United States
| | - Libin Xu
- Department of Medicinal Chemistry, ‡Department of Chemistry, University of Washington , Seattle, Washington 98195, United States
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38
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Bull JN, Coughlan NJA, Bieske EJ. Protomer-Specific Photochemistry Investigated Using Ion Mobility Mass Spectrometry. J Phys Chem A 2017; 121:6021-6027. [DOI: 10.1021/acs.jpca.7b05800] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- James N. Bull
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
| | | | - Evan J. Bieske
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
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39
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Attygalle AB, Xia H, Pavlov J. Influence of Ionization Source Conditions on the Gas-Phase Protomer Distribution of Anilinium and Related Cations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1575-1586. [PMID: 28397015 DOI: 10.1007/s13361-017-1640-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 02/23/2017] [Accepted: 02/25/2017] [Indexed: 06/07/2023]
Abstract
The gas-phase-ion generation technique and specific ion-source settings of a mass spectrometer influence heavily the protonation processes of molecules and the abundance ratio of the generated protomers. Hitherto that has been attributed primarily to the nature of the solvent and the pH. By utilizing electrospray ionization and ion-mobility mass spectrometry (IM-MS), we demonstrate, even in the seemingly trivial case of protonated aniline, that the protomer ratio strongly depends on the source conditions. Under low in-source ion activation, nearly 100% of the N-protomer of aniline is produced, and it can be subsequently converted to the C-protomer by collisional activation effected by increasing the electrical potential difference between the entrance and exit orifices of the first vacuum region. This activation and transformation process takes place even before the ion is mass-selected and subjected to IM separation. Despite the apparent simplicity of the problem, the preferred protonation site of aniline in the gas phase-the amino group or the aromatic ring-has been a topic of controversy. Our results not only provide unambiguous evidence that ring- and nitrogen-protonated aniline can coexist and be interconverted in the gas phase, but also that the ratio of the protomers depends on the internal energy of the original ion. There are many dynamic ion-transformation and fragmentation processes that take place in the different physical compartments of a Synapt G2 HDMS instrument. Such processes can dramatically change the very identity even of small ions, and therefore should be taken into account when interpreting product-ion mass spectra. Graphical Abstract ᅟ.
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Affiliation(s)
- Athula B Attygalle
- Center for Mass Spectrometry, Department of Biomedical Engineering, Chemistry, and Biological Sciences, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.
| | - Hanxue Xia
- Center for Mass Spectrometry, Department of Biomedical Engineering, Chemistry, and Biological Sciences, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Julius Pavlov
- Center for Mass Spectrometry, Department of Biomedical Engineering, Chemistry, and Biological Sciences, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
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40
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Bijlsma L, Bade R, Celma A, Mullin L, Cleland G, Stead S, Hernandez F, Sancho JV. Prediction of Collision Cross-Section Values for Small Molecules: Application to Pesticide Residue Analysis. Anal Chem 2017; 89:6583-6589. [DOI: 10.1021/acs.analchem.7b00741] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Lubertus Bijlsma
- Research
Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat
s/n, E-12071 Castellón, Spain
| | - Richard Bade
- Research
Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat
s/n, E-12071 Castellón, Spain
- School
of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia 5000, Australia
| | - Alberto Celma
- Research
Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat
s/n, E-12071 Castellón, Spain
| | - Lauren Mullin
- Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757, United States
| | - Gareth Cleland
- Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757, United States
| | - Sara Stead
- Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757, United States
| | - Felix Hernandez
- Research
Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat
s/n, E-12071 Castellón, Spain
| | - Juan V. Sancho
- Research
Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat
s/n, E-12071 Castellón, Spain
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41
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Boschmans J, Lemière F, Sobott F. Analyzing complex mixtures of drug-like molecules: Ion mobility as an adjunct to existing liquid chromatography-(tandem) mass spectrometry methods. J Chromatogr A 2017; 1490:80-88. [DOI: 10.1016/j.chroma.2017.02.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 01/24/2017] [Accepted: 02/09/2017] [Indexed: 12/17/2022]
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42
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Zhou Z, Shen X, Tu J, Zhu ZJ. Large-Scale Prediction of Collision Cross-Section Values for Metabolites in Ion Mobility-Mass Spectrometry. Anal Chem 2016; 88:11084-11091. [DOI: 10.1021/acs.analchem.6b03091] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Zhiwei Zhou
- Interdisciplinary
Research
Center on Biology and Chemistry and Shanghai
Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 P. R. China
| | - Xiaotao Shen
- Interdisciplinary
Research
Center on Biology and Chemistry and Shanghai
Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 P. R. China
| | - Jia Tu
- Interdisciplinary
Research
Center on Biology and Chemistry and Shanghai
Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 P. R. China
| | - Zheng-Jiang Zhu
- Interdisciplinary
Research
Center on Biology and Chemistry and Shanghai
Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 P. R. China
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43
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Tata A, Eberlin MN. Catiomers and aniomers: unique classes of isomeric ions. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:1249-1252. [PMID: 28328024 DOI: 10.1002/rcm.7548] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 02/25/2016] [Accepted: 02/28/2016] [Indexed: 06/06/2023]
Affiliation(s)
- Alessandra Tata
- University of Campinas, Institute of Chemistry, UNICAMP-IQ, Campinas, SP, 13083-970, Brazil
| | - Marcos N Eberlin
- University of Campinas, Institute of Chemistry, UNICAMP-IQ, Campinas, SP, 13083-970, Brazil
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44
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Boschmans J, Jacobs S, Williams JP, Palmer M, Richardson K, Giles K, Lapthorn C, Herrebout WA, Lemière F, Sobott F. Combining density functional theory (DFT) and collision cross-section (CCS) calculations to analyze the gas-phase behaviour of small molecules and their protonation site isomers. Analyst 2016; 141:4044-54. [DOI: 10.1039/c5an02456k] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Computational methods are employed to study the protomers in ESI-IM-MS.
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Affiliation(s)
- Jasper Boschmans
- Biomolecular & Analytical Mass Spectrometry group
- Department of Chemistry
- University of Antwerp
- Antwerp
- Belgium
| | - Sam Jacobs
- Molecular Spectroscopy group
- Department of Chemistry
- University of Antwerp
- Antwerp
- Belgium
| | | | | | | | | | - Cris Lapthorn
- Faculty of Engineering & Science
- University of Greenwich
- Chatham
- UK
| | - Wouter A. Herrebout
- Molecular Spectroscopy group
- Department of Chemistry
- University of Antwerp
- Antwerp
- Belgium
| | - Filip Lemière
- Biomolecular & Analytical Mass Spectrometry group
- Department of Chemistry
- University of Antwerp
- Antwerp
- Belgium
| | - Frank Sobott
- Biomolecular & Analytical Mass Spectrometry group
- Department of Chemistry
- University of Antwerp
- Antwerp
- Belgium
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45
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Guo S, Zhang F, Wang H, Zhang M, Zhang Z, Zhang X, Guo Y. Behaviors of Leucine and Isoleucine in Ion Mobility-Quadrupole Time of Flight Mass Spectrometry. CHINESE J CHEM 2015. [DOI: 10.1002/cjoc.201500670] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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46
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Stow SM, Onifer TM, Forsythe JG, Nefzger H, Kwiecien NW, May JC, McLean JA, Hercules DM. Structural Characterization of Methylenedianiline Regioisomers by Ion Mobility-Mass Spectrometry, Tandem Mass Spectrometry, and Computational Strategies. 2. Electrospray Spectra of 3-Ring and 4-Ring Isomers. Anal Chem 2015; 87:6288-96. [PMID: 25971782 PMCID: PMC5642105 DOI: 10.1021/acs.analchem.5b01084] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Building on results from our previous study of 2-ring methylenedianiline (MDA), a combined mass spectrometry approach utilizing ion mobility-mass spectrometry (IM-MS) and tandem mass spectrometry (MS/MS) coupled with computational methods enables the structural characterization of purified 3-ring and 4-ring MDA regioisomers in this current study. The preferred site of protonation for the 3-ring and 4-ring MDA was determined to be on the amino groups. Additionally, the location of the protonated amine along the MDA multimer was found to influence the gas phase stability of these molecules. Fragmentation mechanisms similar to the 2-ring MDA species were observed for both the 3-ring and 4-ring MDA. The structural characterization of 3-ring and 4-ring MDA isomers using modern MS techniques may aid polyurethane synthesis by the characterization of industrial grade MDA, multimeric MDA species, and methylene diphenyl diisocyanate (MDI) mixtures.
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Affiliation(s)
- Sarah M. Stow
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
37235, United States
| | - Tiffany M. Onifer
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
37235, United States
| | - Jay G. Forsythe
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
37235, United States
| | - Hartmut Nefzger
- Bayer MaterialScience AG, 51368 Leverkusen, North Rhine-Westphalia,
Germany
| | - Nicholas W. Kwiecien
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
37235, United States
| | - Jody C. May
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
37235, United States
| | - John A. McLean
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
37235, United States
| | - David M. Hercules
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
37235, United States
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Mol HG, Zomer P, García López M, Fussell RJ, Scholten J, de Kok A, Wolheim A, Anastassiades M, Lozano A, Fernandez Alba A. Identification in residue analysis based on liquid chromatography with tandem mass spectrometry: Experimental evidence to update performance criteria. Anal Chim Acta 2015; 873:1-13. [DOI: 10.1016/j.aca.2015.03.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/28/2015] [Accepted: 03/02/2015] [Indexed: 01/14/2023]
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Warnke S, Seo J, Boschmans J, Sobott F, Scrivens JH, Bleiholder C, Bowers MT, Gewinner S, Schöllkopf W, Pagel K, von Helden G. Protomers of Benzocaine: Solvent and Permittivity Dependence. J Am Chem Soc 2015; 137:4236-42. [DOI: 10.1021/jacs.5b01338] [Citation(s) in RCA: 142] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Stephan Warnke
- Fritz-Haber-Institut
der Max-Planck-Gesellschaft, Faradayweg
4-6, 14195 Berlin, Germany
| | - Jongcheol Seo
- Fritz-Haber-Institut
der Max-Planck-Gesellschaft, Faradayweg
4-6, 14195 Berlin, Germany
| | - Jasper Boschmans
- Biomolecular
and Analytical Mass Spectrometry Group, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Frank Sobott
- Biomolecular
and Analytical Mass Spectrometry Group, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - James H. Scrivens
- School
of Life Sciences, University of Warwick, Coventry CV47AL, United Kingdom
| | - Christian Bleiholder
- Department
of Chemistry and Biochemistry, University of California Santa Barbara, Santa
Barbara, California 93106, United States
| | - Michael T. Bowers
- Department
of Chemistry and Biochemistry, University of California Santa Barbara, Santa
Barbara, California 93106, United States
| | - Sandy Gewinner
- Fritz-Haber-Institut
der Max-Planck-Gesellschaft, Faradayweg
4-6, 14195 Berlin, Germany
| | - Wieland Schöllkopf
- Fritz-Haber-Institut
der Max-Planck-Gesellschaft, Faradayweg
4-6, 14195 Berlin, Germany
| | - Kevin Pagel
- Freie Universität Berlin, Institute of
Chemistry and Biochemistry − Organic Chemistry, Takustrasse 3, 14195 Berlin, Germany
| | - Gert von Helden
- Fritz-Haber-Institut
der Max-Planck-Gesellschaft, Faradayweg
4-6, 14195 Berlin, Germany
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49
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Flick TG, Campuzano IDG, Bartberger MD. Structural Resolution of 4-Substituted Proline Diastereomers with Ion Mobility Spectrometry via Alkali Metal Ion Cationization. Anal Chem 2015; 87:3300-7. [DOI: 10.1021/ac5043285] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Tawnya G. Flick
- Department
of Oral Attribute Sciences, Amgen, Inc., Thousand Oaks, California 91320, United States
| | - Iain D. G. Campuzano
- Department
of Molecular Structure and Characterization, Amgen, Inc., Thousand Oaks, California 91320, United States
| | - Michael D. Bartberger
- Department
of Molecular Structure and Characterization, Amgen, Inc., Thousand Oaks, California 91320, United States
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Kovačević B, Schorr P, Qi Y, Volmer DA. Decay mechanisms of protonated 4-quinolone antibiotics after electrospray ionization and ion activation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:1974-1986. [PMID: 25201456 DOI: 10.1007/s13361-014-0972-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 07/22/2014] [Accepted: 07/27/2014] [Indexed: 06/03/2023]
Abstract
This study presents a detailed experimental investigation of charge isomers of protonated 4-quinolone antibiotics molecules formed during electrospray ionization (ESI) with proposed dissociation mechanisms after collisional activation. Piperazinyl quinolones have been previously shown to exhibit erratic behavior during tandem MS analyses of biological samples, which originated from varying ratios of two isomeric variants formed during ESI. Here, a combination of ESI-collision-induced dissociation (CID), differential ion mobility spectrometry (DMS), high resolution MS, and density functional theory (DFT) was used to investigate the underlying mechanisms of isomer formation and their individual dissociation behaviors. The study focused on ciprofloxacin; major findings were confirmed using structurally related 4-quinolones. DFT calculations showed a reversal of basicity for piperazinyl quinolones between liquid and gas phase. We provide an experimental comparison and theoretical treatment of factors influencing the formation ratio of the charge isomers during ESI, including solvent pH, protic/aprotic nature of solvent, and structural effects such as pK a and proton affinity. The actual dissociation mechanisms of the isomers of the protonated molecules were studied by separating the individual isomers via DMS-MS, which allowed type-specific CID spectra to be recorded. Both primary CID reactions of the two charge isomers originated from the same carboxyl group by charge-remote (CO(2) loss) and charge-mediated (H(2)O loss) fragmentation of the piperazinyl quinolones, depending on whether the proton resides on the more basic keto or the piperazinyl group, followed by a number of secondary dissociation reactions. The proposed mechanisms were supported by calculated energies of precursors, transition states, and products for competing pathways.
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