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Carbonell-Rozas L, Hernández-Mesa M, Righetti L, Monteau F, Lara FJ, Gámiz-Gracia L, Bizec BL, Dall'Asta C, García-Campaña AM, Dervilly G. Ion mobility-mass spectrometry to extend analytical performance in the determination of ergot alkaloids in cereal samples. J Chromatogr A 2022; 1682:463502. [PMID: 36174373 DOI: 10.1016/j.chroma.2022.463502] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/30/2022] [Accepted: 09/12/2022] [Indexed: 11/28/2022]
Abstract
This work evaluates the potential of ion mobility spectrometry (IMS) to improve the analytical performance of current liquid chromatography-mass spectrometry (LC-MS) workflows applied to the determination of ergot alkaloids (EAs) in cereal samples. Collision cross section (CCS) values for EA epimers are reported for the first time to contribute to their unambiguous identification. Additionally, CCS values have been inter-laboratory cross-validated and compared with CCS values predicted by machine-learning models. Slight differences were observed in terms of CCS values for ergotamine, ergosine and ergocristine and their corresponding epimers (from 3.3 to 4%), being sufficient to achieve a satisfactory peak-to-peak resolution for their unequivocal identification. A LC-travelling wave ion mobility (TWIM)-MS method has been developed for the analysis of EAs in barley and wheat samples. Signal-to-noise ratio (S/N) was improved between 2.5 and 4-fold compared to the analog LC-TOF-MS method. The quality of the extracted ion chromatograms was also improved by using IMS.
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Affiliation(s)
- Laura Carbonell-Rozas
- Oniris, INRAE, LABERCA, 44300 Nantes, France; Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
| | - Maykel Hernández-Mesa
- Oniris, INRAE, LABERCA, 44300 Nantes, France; Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| | - Laura Righetti
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | | | - Francisco J Lara
- Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
| | - Laura Gámiz-Gracia
- Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
| | | | - Chiara Dall'Asta
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | - Ana M García-Campaña
- Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
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2
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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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3
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Larriba-Andaluz C, Prell JS. Fundamentals of ion mobility in the free molecular regime. Interlacing the past, present and future of ion mobility calculations. INT REV PHYS CHEM 2020. [DOI: 10.1080/0144235x.2020.1826708] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Carlos Larriba-Andaluz
- Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - James S. Prell
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA
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4
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Chouinard CD, Nagy G, Smith RD, Baker ES. Ion Mobility-Mass Spectrometry in Metabolomic, Lipidomic, and Proteomic Analyses. ADVANCES IN ION MOBILITY-MASS SPECTROMETRY: FUNDAMENTALS, INSTRUMENTATION AND APPLICATIONS 2019. [DOI: 10.1016/bs.coac.2018.11.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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5
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Mu Y, Schulz BL, Ferro V. Applications of Ion Mobility-Mass Spectrometry in Carbohydrate Chemistry and Glycobiology. Molecules 2018; 23:molecules23102557. [PMID: 30301275 PMCID: PMC6222328 DOI: 10.3390/molecules23102557] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/26/2018] [Accepted: 10/04/2018] [Indexed: 01/25/2023] Open
Abstract
Carbohydrate analyses are often challenging due to the structural complexity of these molecules, as well as the lack of suitable analytical tools for distinguishing the vast number of possible isomers. The coupled technique, ion mobility-mass spectrometry (IM-MS), has been in use for two decades for the analysis of complex biomolecules, and in recent years it has emerged as a powerful technique for the analysis of carbohydrates. For carbohydrates, most studies have focused on the separation and characterization of isomers in biological samples. IM-MS is capable of separating isomeric ions by drift time, and further characterizing them by mass analysis. Applications of IM-MS in carbohydrate analysis are extremely useful and important for understanding many biological mechanisms and for the determination of disease states, although efforts are still needed for higher sensitivity and resolution.
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Affiliation(s)
- Yuqing Mu
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane 4072, Australia.
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane 4072, Australia.
| | - Benjamin L Schulz
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane 4072, Australia.
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane 4072, Australia.
- Australian Research Council Industrial Transformation Training Centre for Biopharmaceutical Innovation, The University of Queensland, Brisbane 4072, Australia.
| | - Vito Ferro
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane 4072, Australia.
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane 4072, Australia.
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6
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Erabelli R, Xu S, Attygalle AB. Gas-phase protomers of p-(dimethylamino)chalcone investigated by travelling-wave ion mobility mass spectrometry (TWIMS). JOURNAL OF MASS SPECTROMETRY : JMS 2018; 53:954-962. [PMID: 29989269 DOI: 10.1002/jms.4265] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 06/24/2018] [Accepted: 06/27/2018] [Indexed: 06/08/2023]
Abstract
Results from ion-mobility (IM) separation experiments demonstrate that O- and N-protomers of p-(dimethylamino)chalcone (p-DMAC) can coexist in the gas phase. The relative populations of the two protomers strongly depend on the ion-generating settings and the conditions the precursor ions experience from the point of their gas-phase inception to the time of their detection. Under relatively dry source conditions, the ratio of the gas-phase protomers generated under helium-plasma ionization (HePI) conditions is biased towards the thermodynamically favored O-protomer. However, when the humidity of the enclosed ion source was increased, the IM arrival-time distribution profile of the mass-selected protonated precursor of p-DMAC changed rapidly to one dominated by the N-protomer. Under spray-ionization conditions, the formation of the thermodynamically less favored protomer has been generally attributed to a phenomenon called kinetic trapping. Herein, we demonstrate that the population of thermodynamically less favored N-protomer can be dramatically increased simply by introducing water vapor to the HePI ion source.
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Affiliation(s)
- Ramu Erabelli
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey
| | - Sihang Xu
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey
| | - Athula B Attygalle
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey
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7
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Jurado-Campos N, Garrido-Delgado R, Martínez-Haya B, Eiceman GA, Arce L. Stability of proton-bound clusters of alkyl alcohols, aldehydes and ketones in Ion Mobility Spectrometry. Talanta 2018; 185:299-308. [DOI: 10.1016/j.talanta.2018.03.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 03/06/2018] [Accepted: 03/11/2018] [Indexed: 10/17/2022]
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8
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Sachse T, Martínez TJ, Dietzek B, Presselt M. A program for automatically predicting supramolecular aggregates and its application to urea and porphin. J Comput Chem 2018; 39:763-772. [PMID: 29297589 DOI: 10.1002/jcc.25151] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 12/04/2017] [Accepted: 12/07/2017] [Indexed: 11/08/2022]
Abstract
Not only the molecular structure but also the presence or absence of aggregates determines many properties of organic materials. Theoretical investigation of such aggregates requires the prediction of a suitable set of diverse structures. Here, we present the open-source program EnergyScan for the unbiased prediction of geometrically diverse sets of small aggregates. Its bottom-up approach is complementary to existing ones by performing a detailed scan of an aggregate's potential energy surface, from which diverse local energy minima are selected. We crossvalidate this approach by predicting both literature-known and heretofore unreported geometries of the urea dimer. We also predict a diverse set of dimers of the less intensely studied case of porphin, which we investigate further using quantum chemistry. For several dimers, we find strong deviations from a reference absorption spectrum, which we explain using computed transition densities. This proof of principle clearly shows that EnergyScan successfully predicts aggregates exhibiting large structural and spectral diversity. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Torsten Sachse
- Friedrich Schiller University, Institute of Physical Chemistry, Helmholtzweg 4, 07743, Jena, Germany.,Leibniz Institute of Photonic Technology Jena (IPHT), Research Department Functional Interfaces, Albert-Einstein-Straße 9, Jena, 07745, Germany
| | - Todd J Martínez
- Stanford University, Department of Chemistry and the PULSE Institute, 333 Campus Drive, Stanford, California 94305.,SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, California, 94025
| | - Benjamin Dietzek
- Friedrich Schiller University, Institute of Physical Chemistry, Helmholtzweg 4, 07743, Jena, Germany.,Center for Energy and Environmental Chemistry Jena, Humboldtstraße 10, Jena, 07743, Germany
| | - Martin Presselt
- Leibniz Institute of Photonic Technology Jena (IPHT), Research Department Functional Interfaces, Albert-Einstein-Straße 9, Jena, 07745, Germany.,SciClus GmbH & Co. KG, Moritz-von-Rohr-Straße 1a, Jena, 07745, Germany
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9
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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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10
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Lee JW, Lee HHL, Davidson KL, Bush MF, Kim HI. Structural characterization of small molecular ions by ion mobility mass spectrometry in nitrogen drift gas: improving the accuracy of trajectory method calculations. Analyst 2018; 143:1786-1796. [DOI: 10.1039/c8an00270c] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
An accurate theoretical collision cross section calculation method in nitrogen was developed for reliable structural ion mobility mass spectrometry.
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Affiliation(s)
- Jong Wha Lee
- Center for Analytical Chemistry
- Division of Chemical and Medical Metrology
- Korea Research Institute of Standards and Science (KRISS)
- Daejeon 34113
- Republic of Korea
| | - Hyun Hee L. Lee
- Department of Chemistry
- Korea University
- Seoul 02841
- Republic of Korea
| | | | | | - Hugh I. Kim
- Department of Chemistry
- Korea University
- Seoul 02841
- Republic of Korea
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11
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Gunzer F. Evaluation of calculated negative mode ion mobilities of small molecules in air. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2017; 23:369-375. [PMID: 29183198 DOI: 10.1177/1469066717729299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ion mobility spectrometry is a well-known technique employed for the detection and analysis of gaseous substances. In pharmaceutical applications, it is furthermore used for structural analysis of compounds, especially in combination with mass spectrometry. In this field, the comparison of calculated collision cross sections and ion mobilities of theoretic model compounds with experimental values measured with ion mobility spectrometers helps to determine the compound's structure. For positive mode ion mobility spectrometry, the calculated mobilities using the Trajectory Method show in general a deviation of 10% or less from experimental values. In this article, it was analyzed how well the calculated values reproduce the experimental values obtained with negative mode ion mobility spectrometry including symmetric and asymmetric analyte clusters. Furthermore, the influence of four different partial charge models on the results was investigated.
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Affiliation(s)
- Frank Gunzer
- Department of Electronics Engineering, Information Engineering and Technology Faculty, German University in Cairo, Entrance El Tagamoa El Khames, New Cairo, Egypt
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12
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Chouinard CD, Cruzeiro VWD, Beekman CR, Roitberg AE, Yost RA. Investigating Differences in Gas-Phase Conformations of 25-Hydroxyvitamin D3 Sodiated Epimers using Ion Mobility-Mass Spectrometry and Theoretical Modeling. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1497-1505. [PMID: 28417307 DOI: 10.1007/s13361-017-1673-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/26/2017] [Accepted: 03/28/2017] [Indexed: 06/07/2023]
Abstract
Drift tube ion mobility coupled with mass spectrometry was used to investigate the gas-phase structure of 25-hydroxyvitamin D3 (25OHD3) and D2 (25OHD2) epimers, and to evaluate its potential in rapid separation of these compounds. Experimental results revealed two distinct drift species for the 25OHD3 sodiated monomer, whereas only one of these conformations was observed for its epimer (epi25OHD3). The unique species allowed 25OHD3 to be readily distinguished, and the same pattern was observed for 25OHD2 epimers. Theoretical modeling of 25OHD3 epimers identified energetically stable gas-phase structures, indicating that both compounds may adopt a compact "closed" conformation, but that 25OHD3 may also adopt a slightly less energetically favorable "open" conformation that is not accessible to its epimer. Calculated theoretical collision cross-sections for these structures agreed with experimental results to <2%. Experimentation indicated that additional energy in the ESI source (i.e., increased temperature, spray voltage) affected the ratio of 25OHD3 conformations, with the less energetically favorable "open" conformation increasing in relative intensity. Finally, LC-IM-MS results yielded linear quantitation of 25OHD3, in the presence of the epimer interference, at biologically relevant concentrations. This study demonstrates that ion mobility can be used in tandem with theoretical modeling to determine structural differences that contribute to drift separation. These separation capabilities provide potential for rapid (<60 ms) identification of 25OHD3 and 25OHD2 in mixtures with their epimers. Graphical Abstract ᅟ.
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Affiliation(s)
| | - Vinícius Wilian D Cruzeiro
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA
- CAPES Foundation, Ministry of Education of Brazil, Brasília, DF, 70040-020, Brazil
| | | | - Adrian E Roitberg
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA
| | - Richard A Yost
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA.
- Southeast Center for Integrated Metabolomics (SECIM), University of Florida, Gainesville, FL, USA.
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13
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Chouinard CD, Cruzeiro VWD, Roitberg AE, Yost RA. Experimental and Theoretical Investigation of Sodiated Multimers of Steroid Epimers with Ion Mobility-Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:323-331. [PMID: 27914014 PMCID: PMC5478531 DOI: 10.1007/s13361-016-1525-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Revised: 10/06/2016] [Accepted: 10/08/2016] [Indexed: 05/11/2023]
Abstract
Ion mobility-mass spectrometry (IM-MS) has recently seen increased use in the analysis of small molecules, especially in the field of metabolomics, for increased breadth of information and improved separation of isomers. In this study, steroid epimers androsterone and trans-androsterone were analyzed with IM-MS to investigate differences in their relative mobilities. Although sodiated monomers exhibited very similar collision cross-sections (CCS), baseline separation was observed for the sodiated dimer species (RS = 1.81), with measured CCS of 242.6 and 256.3 Å2, respectively. Theoretical modeling was performed to determine the most energetically stable structures of solution-phase and gas-phase monomer and dimer structures. It was revealed that these epimers differ in their preferred dimer binding mode in solution phase: androsterone adopts a R=O - Na+ - OH-R' configuration, whereas trans-androsterone adopts a R=O - Na+ - O=R' configuration. This difference contributes to a significant structural variation, and subsequent CCS calculations based on these structures relaxed in the gas phase were in agreement with experimentally measured values (ΔCCS ~ 5%). Additionally, these calculations accurately predicted the relative difference in mobility between the epimers. This study illustrates the power of combining experimental and theoretical results to better elucidate gas-phase structures. Graphical Abstract ᅟ.
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Affiliation(s)
| | - Vinícius Wilian D Cruzeiro
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA
- CAPES Foundation, Ministry of Education of Brazil, Brasília, DF, 70040-020, Brazil
| | - Adrian E Roitberg
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA
| | - Richard A Yost
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA.
- Southeast Center for Integrated Metabolomics (SECIM), University of Florida, Gainesville, FL, 32611, USA.
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14
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Lee JW, Davidson KL, Bush MF, Kim HI. Collision cross sections and ion structures: development of a general calculation method via high-quality ion mobility measurements and theoretical modeling. Analyst 2017; 142:4289-4298. [DOI: 10.1039/c7an01276d] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Theoretical collision cross section calculations revisited for reliable ion structural studies.
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Affiliation(s)
- Jong Wha Lee
- Center for Analytical Chemistry
- Division of Chemical and Medical Metrology
- Korea Research Institute of Standards and Science (KRISS)
- Daejeon 34113
- Republic of Korea
| | | | | | - Hugh I. Kim
- Department of Chemistry
- Korea University
- Seoul 02841
- Republic of Korea
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15
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Kune C, Far J, De Pauw E. Accurate Drift Time Determination by Traveling Wave Ion Mobility Spectrometry: The Concept of the Diffusion Calibration. Anal Chem 2016; 88:11639-11646. [PMID: 27934120 DOI: 10.1021/acs.analchem.6b03215] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ion mobility spectrometry (IMS) is a gas phase separation technique, which relies on differences in collision cross section (CCS) of ions. Ionic clouds of unresolved conformers overlap if the CCS difference is below the instrumental resolution expressed as CCS/ΔCCS. The experimental arrival time distribution (ATD) peak is then a superimposition of the various contributions weighted by their relative intensities. This paper introduces a strategy for accurate drift time determination using traveling wave ion mobility spectrometry (TWIMS) of poorly resolved or unresolved conformers. This method implements through a calibration procedure the link between the peak full width at half-maximum (fwhm) and the drift time of model compounds for wide range of settings for wave heights and velocities. We modified a Gaussian equation, which achieves the deconvolution of ATD peaks where the fwhm is fixed according to our calibration procedure. The new fitting Gaussian equation only depends on two parameters: The apex of the peak (A) and the mean drift time value (μ). The standard deviation parameter (correlated to fwhm) becomes a function of the drift time. This correlation function between μ and fwhm is obtained using the TWIMS calibration procedure which determines the maximum instrumental ion beam diffusion under limited and controlled space charge effect using ionic compounds which are detected as single conformers in the gas phase. This deconvolution process has been used to highlight the presence of poorly resolved conformers of crown ether complexes and peptides leading to more accurate CCS determinations in better agreement with quantum chemistry predictions.
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Affiliation(s)
- Christopher Kune
- Laboratory of Mass Spectrometry, University of Liege , Quartier Agora, Allée du Six Aout 11, B-4000, Liege, Belgium
| | - Johann Far
- Laboratory of Mass Spectrometry, University of Liege , Quartier Agora, Allée du Six Aout 11, B-4000, Liege, Belgium
| | - Edwin De Pauw
- Laboratory of Mass Spectrometry, University of Liege , Quartier Agora, Allée du Six Aout 11, B-4000, Liege, Belgium
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16
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Benigni P, Marin R, Molano-Arevalo JC, Garabedian A, Wolff JJ, Ridgeway ME, Park MA, Fernandez-Lima F. Towards the Analysis of High Molecular Weight Proteins and Protein complexes using TIMS-MS. INTERNATIONAL JOURNAL FOR ION MOBILITY SPECTROMETRY : OFFICIAL PUBLICATION OF THE INTERNATIONAL SOCIETY FOR ION MOBILITY SPECTROMETRY 2016; 19:95-104. [PMID: 27818614 PMCID: PMC5091298 DOI: 10.1007/s12127-016-0201-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 05/26/2016] [Accepted: 05/29/2016] [Indexed: 01/02/2023]
Abstract
In the present work, we demonstrate the potential and versatility of TIMS for the analysis of proteins, DNA-protein complexes and protein-protein complexes in their native and denatured states. In addition, we show that accurate CCS measurement are possible and in good agreement with previously reported CCS values using other IMS analyzers (<5% difference). The main challenges for the analysis of high mass proteins and protein complexes in the mobility and m/z domain are described. That is, the analysis of high molecular weight systems in their native state may require the use of higher electric fields or a compromise in the TIMS mobility resolution by reducing the bath gas velocity in order to effectively trap at lower electric fields. This is the first report of CCS measurements of high molecular weight biomolecules and biomolecular complexes (~ 150 kDa) using TIMS-MS.
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Affiliation(s)
- Paolo Benigni
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Rebecca Marin
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
| | | | - Alyssa Garabedian
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
| | | | | | - Melvin A. Park
- Bruker Daltonics, Inc., Billerica, Massachusetts 01821, USA
| | - Francisco Fernandez-Lima
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Science Institute, Florida International University, Miami, FL 33199, USA
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17
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Larriba-Andaluz C, Fernández-García J, Ewing MA, Hogan CJ, Clemmer DE. Gas molecule scattering & ion mobility measurements for organic macro-ions in He versus N2 environments. Phys Chem Chem Phys 2016; 17:15019-29. [PMID: 25988389 DOI: 10.1039/c5cp01017a] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A pending issue in linking ion mobility measurements to ion structures is that the collisional cross section (CCS, the measured structural parameter in ion mobility spectrometry) of an ion is strongly dependent upon the manner in which gas molecules effectively impinge on and are reemitted from ion surfaces (when modeling ions as fixed structures). To directly examine the gas molecule impingement and reemission processes and their influence, we measured the CCSs of positively charged ions of room temperature ionic liquids 1-ethyl-3-methylimidazolium dicyanamide (EMIM-N(CN)2) and 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM-BF4) in N2 using a differential mobility analyzer-mass spectrometer (DMA-MS) and in He using a drift tube mobility spectrometer-mass spectrometer (DT-MS). Cluster ions, generated via electrosprays, took the form (AB)N(A)z, spanning up to z = 20 and with masses greater than 100 kDa. As confirmed by molecular dynamics simulations, at the measurement temperature (∼300 K), such cluster ions took on globular conformations in the gas phase. Based upon their attained charge levels, in neither He nor N2 did the ion-induced dipole potential significantly influence gas molecule-ion collisions. Therefore, differences in the CCSs measured for ions in the two different gases could be primarily attributed to differences in gas molecule behavior upon collision with ions. Overwhelmingly, by comparison of predicted CCSs with selected input impingement-reemission laws to measurements, we find that in N2, gas molecules collide with ions diffusely--they are reemitted at random angles relative to the gas molecule incoming angle--and inelastically. Meanwhile, in He, gas molecules collide specularly and elastically and are emitted from ion surfaces at determined angles. The results can be rationalized on the basis of the momentum transferred per collision; in the case of He, individual gas molecule collisions minimally perturb the atoms within a cluster ion (internal motion), while in the case of N2, individual gas molecules have sufficiently large momentum to alter the internal motion in organic ions.
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Affiliation(s)
- Carlos Larriba-Andaluz
- University of Minnesota, Mechanical Engineering Department, 111 Church st. RM 2101A, Minneapolis, MN 55455, USA.
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18
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Reading E, Munoz-Muriedas J, Roberts AD, Dear GJ, Robinson CV, Beaumont C. Elucidation of Drug Metabolite Structural Isomers Using Molecular Modeling Coupled with Ion Mobility Mass Spectrometry. Anal Chem 2016; 88:2273-80. [DOI: 10.1021/acs.analchem.5b04068] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Eamonn Reading
- Department
of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford OX1 3QZ, U.K
| | - Jordi Munoz-Muriedas
- Chemical
Sciences, Computational Chemistry, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Andrew D. Roberts
- Drug
Metabolism and Pharmacokinetics, GlaxoSmithKline, Ware, Hertfordshire SG12 0DP, U.K
| | - Gordon J. Dear
- Drug
Metabolism and Pharmacokinetics, GlaxoSmithKline, Ware, Hertfordshire SG12 0DP, U.K
| | - Carol V. Robinson
- Department
of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford OX1 3QZ, U.K
| | - Claire Beaumont
- Drug
Metabolism and Pharmacokinetics, GlaxoSmithKline, Ware, Hertfordshire SG12 0DP, U.K
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19
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Gunzer F. Comparison of Experimental and Calculated Ion Mobilities of Small Molecules in Air. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2016; 2016:6246415. [PMID: 27298751 PMCID: PMC4889856 DOI: 10.1155/2016/6246415] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 05/05/2016] [Indexed: 05/06/2023]
Abstract
Ion mobility spectrometry is a well-known technique for analyzing gases. Examples are military applications, but also safety related applications, for example, for protection of employees in industries working with hazardous gases. In the last 15 years, this technique has been further developed as a tool for structural analysis, for example, in pharmaceutical applications. In particular, the collision cross section, which is related to the mobility, is of interest here. With help of theoretic principles, it is possible to develop molecular models that can be verified by the comparison of their calculated cross sections with experimental data. In this paper, it is analyzed how well the ion trajectory method is suitable to reproduce the measured ion mobility of small organic molecules such as the water clusters forming the positively charged reactant ions, simple aromatic substances, and n-alkanes.
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Affiliation(s)
- Frank Gunzer
- Information Engineering and Technology Faculty, German University in Cairo, El Tagamoa El Khames, Cairo, Egypt
- *Frank Gunzer:
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Bataglion GA, Souza GHMF, Heerdt G, Morgon NH, Dutra JDL, Freire RO, Eberlin MN, Tata A. Separation of glycosidic catiomers by TWIM-MS using CO2 as a drift gas. JOURNAL OF MASS SPECTROMETRY : JMS 2015; 50:336-343. [PMID: 25800015 DOI: 10.1002/jms.3532] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 09/22/2014] [Accepted: 10/16/2014] [Indexed: 06/04/2023]
Abstract
Traveling wave ion mobility mass spectrometry (TWIM-MS) is shown to be able to separate and characterize several isomeric forms of diterpene glycosides stevioside (Stv) and rebaudioside A (RebA) that are cationized by Na(+) and K(+) at different sites. Determination and characterization of these coexisting isomeric species, herein termed catiomers, arising from cationization at different and highly competitive coordinating sites, is particularly challenging for glycosides. To achieve this goal, the advantage of using CO2 as a more massive and polarizable drift gas, over N2, was demonstrated. Post-TWIM-MS/MS experiments were used to confirm the separation. Optimization of the possible geometries and cross-sectional calculations for mobility peak assignments were also performed.
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Affiliation(s)
- Giovana A Bataglion
- ThoMSon Mass Spectrometry Laboratory, Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP, Brazil
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21
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Poyer S, Loutelier-Bourhis C, Coadou G, Mondeguer F, Enche J, Bossée A, Hess P, Afonso C. Identification and separation of saxitoxins using hydrophilic interaction liquid chromatography coupled to traveling wave ion mobility-mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2015; 50:175-181. [PMID: 25601690 DOI: 10.1002/jms.3515] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 09/19/2014] [Accepted: 09/22/2014] [Indexed: 06/04/2023]
Abstract
The aim of this work was to develop a reliable and efficient analytical method to characterise and differentiate saxitoxin analogues (STX), including sulphated (gonyautoxins, GTX) and non-sulphated analogues. For this purpose, hydrophilic interaction liquid chromatography (HILIC) was used to separate sulphated analogues. We also resorted to ion mobility spectrometry to differentiate the STX analogues because this technique adds a new dimension of separation based on ion gas phase conformation. Positive and negative ionisation modes were used for gonyautoxins while positive ionisation mode was used for non-sulphated analogues. Subsequently, the coupling of these three complementary techniques, HILIC-IM-MS, permitted the separation and identification of STX analogues; isomer differentiation was achieved in HILIC dimension while non-sulphated analogues were separated in the IM-MS dimension. Additional structural characteristics concerning the conformation of STXs could be obtained using IM-MS measurements. Thus, the collision cross sections (CCS) of STXs are reported for the first time in the positive ionisation mode. These experimental CCSs correlated well with the calculated CCS values using the trajectory method.
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Affiliation(s)
- Salomé Poyer
- Normandie Université, COBRA, UMR 6014 et FR 3038, Université de Rouen, INSA de Rouen, CNRS, IRCOF,1 rue Tesnière, 76821, Mont-Saint-Aignan Cedex, France
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22
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Stow SM, Goodwin CR, Kliman M, Bachmann BO, McLean JA, Lybrand TP. Distance geometry protocol to generate conformations of natural products to structurally interpret ion mobility-mass spectrometry collision cross sections. J Phys Chem B 2014; 118:13812-20. [PMID: 25360896 PMCID: PMC4259499 DOI: 10.1021/jp509398e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Ion mobility-mass spectrometry (IM-MS)
allows the separation of
ionized molecules based on their charge-to-surface area (IM) and mass-to-charge
ratio (MS), respectively. The IM drift time data that is obtained
is used to calculate the ion-neutral collision cross section (CCS)
of the ionized molecule with the neutral drift gas, which is directly
related to the ion conformation and hence molecular size and shape.
Studying the conformational landscape of these ionized molecules computationally
provides interpretation to delineate the potential structures that
these CCS values could represent, or conversely, structural motifs
not consistent with the IM data. A challenge in the IM-MS community
is the ability to rapidly compute conformations to interpret natural
product data, a class of molecules exhibiting a broad range of biological
activity. The diversity of biological activity is, in part, related
to the unique structural characteristics often observed for natural
products. Contemporary approaches to structurally interpret IM-MS
data for peptides and proteins typically utilize molecular dynamics
(MD) simulations to sample conformational space. However, MD calculations
are computationally expensive, they require a force field that accurately
describes the molecule of interest, and there is no simple metric
that indicates when sufficient conformational sampling has been achieved.
Distance geometry is a computationally inexpensive approach that creates
conformations based on sampling different pairwise distances between
the atoms within the molecule and therefore does not require a force
field. Progressively larger distance bounds can be used in distance
geometry calculations, providing in principle a strategy to assess
when all plausible conformations have been sampled. Our results suggest
that distance geometry is a computationally efficient and potentially
superior strategy for conformational analysis of natural products
to interpret gas-phase CCS data.
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Affiliation(s)
- Sarah M Stow
- Department of Chemistry, ‡Department of Pharmacology, §Vanderbilt Institute of Chemical Biology, ∥Vanderbilt Institute of Integrative Biosystems Research and Education, ⊥Center for Structural Biology, Vanderbilt University , Nashville, Tennessee 37235, United States
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23
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Gregori B, Guidoni L, Chiavarino B, Scuderi D, Nicol E, Frison G, Fornarini S, Crestoni ME. Vibrational Signatures of S-Nitrosoglutathione as Gaseous, Protonated Species. J Phys Chem B 2014; 118:12371-82. [DOI: 10.1021/jp5072742] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
| | - Leonardo Guidoni
- Dipartimento
di Scienza Fisiche e Chimiche, Università degli Studi dell’Aquila, Via Vetoio 2, Coppito, L’Aquila I-64100, Italy
| | | | - Debora Scuderi
- Laboratoire
de Chimie Physique, UMR8000 CNRS, Faculté des Sciences, Université Paris-Sud, Batiment 350, 91405 Orsay Cedex, France
| | - Edith Nicol
- Laboratoire
de Chimie Moléculaire, Ecole Polytechnique and CNRS, 91128 Palaiseau Cedex, France
| | - Gilles Frison
- Laboratoire
de Chimie Moléculaire, Ecole Polytechnique and CNRS, 91128 Palaiseau Cedex, France
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Morrison LJ, Wysocki VH. Gas-Phase Helical Peptides Mimic Solution-Phase Behavior. J Am Chem Soc 2014; 136:14173-83. [PMID: 25203898 DOI: 10.1021/ja507298e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Lindsay J. Morrison
- Ohio State University, 484
West 12th Avenue, Columbus, Ohio 43210, United States
| | - Vicki H. Wysocki
- Ohio State University, 484
West 12th Avenue, Columbus, Ohio 43210, United States
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25
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Molecular simulation-based structural prediction of protein complexes in mass spectrometry: the human insulin dimer. PLoS Comput Biol 2014; 10:e1003838. [PMID: 25210764 PMCID: PMC4161290 DOI: 10.1371/journal.pcbi.1003838] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 07/26/2014] [Indexed: 01/02/2023] Open
Abstract
Protein electrospray ionization (ESI) mass spectrometry (MS)-based techniques are widely used to provide insight into structural proteomics under the assumption that non-covalent protein complexes being transferred into the gas phase preserve basically the same intermolecular interactions as in solution. Here we investigate the applicability of this assumption by extending our previous structural prediction protocol for single proteins in ESI-MS to protein complexes. We apply our protocol to the human insulin dimer (hIns2) as a test case. Our calculations reproduce the main charge and the collision cross section (CCS) measured in ESI-MS experiments. Molecular dynamics simulations for 0.075 ms show that the complex maximizes intermolecular non-bonded interactions relative to the structure in water, without affecting the cross section. The overall gas-phase structure of hIns2 does exhibit differences with the one in aqueous solution, not inferable from a comparison with calculated CCS. Hence, care should be exerted when interpreting ESI-MS proteomics data based solely on NMR and/or X-ray structural information.
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26
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Menikarachchi LC, Hamdalla MA, Hill DW, Grant DF. Chemical structure identification in metabolomics: computational modeling of experimental features. Comput Struct Biotechnol J 2013; 5:e201302005. [PMID: 24688698 PMCID: PMC3962140 DOI: 10.5936/csbj.201302005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 12/20/2012] [Accepted: 12/24/2012] [Indexed: 11/30/2022] Open
Abstract
The identification of compounds in complex mixtures remains challenging despite recent advances in analytical techniques. At present, no single method can detect and quantify the vast array of compounds that might be of potential interest in metabolomics studies. High performance liquid chromatography/mass spectrometry (HPLC/MS) is often considered the analytical method of choice for analysis of biofluids. The positive identification of an unknown involves matching at least two orthogonal HPLC/MS measurements (exact mass, retention index, drift time etc.) against an authentic standard. However, due to the limited availability of authentic standards, an alternative approach involves matching known and measured features of the unknown compound with computationally predicted features for a set of candidate compounds downloaded from a chemical database. Computationally predicted features include retention index, ECOM50 (energy required to decompose 50% of a selected precursor ion in a collision induced dissociation cell), drift time, whether the unknown compound is biological or synthetic and a collision induced dissociation (CID) spectrum. Computational predictions are used to filter the initial “bin” of candidate compounds. The final output is a ranked list of candidates that best match the known and measured features. In this mini review, we discuss cheminformatics methods underlying this database search-filter identification approach.
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Affiliation(s)
- Lochana C Menikarachchi
- Department of Pharmaceutical Sciences, University of Connecticut, 69 N Eagleville Rd, Storrs, CT 06269, United States
| | - Mai A Hamdalla
- Department of Computer Science & Engineering, University of Connecticut, 371 Fairfield Road, Unit 2155 Storrs, CT 06269, United States
| | - Dennis W Hill
- Department of Pharmaceutical Sciences, University of Connecticut, 69 N Eagleville Rd, Storrs, CT 06269, United States
| | - David F Grant
- Department of Pharmaceutical Sciences, University of Connecticut, 69 N Eagleville Rd, Storrs, CT 06269, United States
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27
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Menikarachchi LC, Cawley S, Hill DW, Hall LM, Hall L, Lai S, Wilder J, Grant DF. MolFind: a software package enabling HPLC/MS-based identification of unknown chemical structures. Anal Chem 2012; 84:9388-94. [PMID: 23039714 PMCID: PMC3523192 DOI: 10.1021/ac302048x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In this paper, we present MolFind, a highly multithreaded pipeline type software package for use as an aid in identifying chemical structures in complex biofluids and mixtures. MolFind is specifically designed for high-performance liquid chromatography/mass spectrometry (HPLC/MS) data inputs typical of metabolomics studies where structure identification is the ultimate goal. MolFind enables compound identification by matching HPLC/MS-based experimental data obtained for an unknown compound with computationally derived HPLC/MS values for candidate compounds downloaded from chemical databases such as PubChem. The downloaded "bins" consist of all compounds matching the monoisotopic molecular weight of the unknown. The computational HPLC/MS values predicted include retention index (RI), ECOM(50) (energy required to fragment 50% of a selected precursor ion), drift time, and collision induced dissociation (CID) spectrum. RI, ECOM(50), and drift-time models are used for filtering compounds downloaded from PubChem. The remaining candidates are then ranked based on CID spectra matching. Current RI and ECOM(50) models allow for the removal of about 28% of compounds from PubChem bins. Our estimates suggest that this could be improved to as much as 87% with additional chemical structures included in the computational models. Quantitative structure property relationship-based modeling of drift times showed a better correlation with experimentally determined drift times than did Mobcal cross-sectional areas. In 23 of 35 example cases, filtering PubChem bins with RI and ECOM(50) predictive models resulted in improved ranking of the unknown compounds compared to previous studies using CID spectra matching alone. In 19 of 35 examples, the correct candidate was ranked within the top 20 compounds in bins containing an average of 1635 compounds.
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Affiliation(s)
- Lochana C. Menikarachchi
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, United States
| | - Shannon Cawley
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, United States
| | - Dennis W. Hill
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, United States
| | - L. Mark Hall
- Hall Associates Consulting, Quincy, Massachusetts, United States
| | - Lowell Hall
- Department of Chemistry, Eastern Nazarene College, Quincy, Massachusetts, United States
| | - Steven Lai
- Waters Corporation, Beverly, Massachusetts, United States
| | - Janine Wilder
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, United States
| | - David F. Grant
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, United States
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