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Wisanpitayakorn P, Sartyoungkul S, Kurilung A, Sirivatanauksorn Y, Visessanguan W, Sathirapongsasuti N, Khoomrung S. Accurate Prediction of Ion Mobility Collision Cross-Section Using Ion's Polarizability and Molecular Mass with Limited Data. J Chem Inf Model 2024; 64:1533-1542. [PMID: 38393779 PMCID: PMC10934814 DOI: 10.1021/acs.jcim.3c01491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 01/26/2024] [Accepted: 02/12/2024] [Indexed: 02/25/2024]
Abstract
The rotationally averaged collision cross-section (CCS) determined by ion mobility-mass spectrometry (IM-MS) facilitates the identification of various biomolecules. Although machine learning (ML) models have recently emerged as a highly accurate approach for predicting CCS values, they rely on large data sets from various instruments, calibrants, and setups, which can introduce additional errors. In this study, we identified and validated that ion's polarizability and mass-to-charge ratio (m/z) have the most significant predictive power for traveling-wave IM CCS values in relation to other physicochemical properties of ions. Constructed solely based on these two physicochemical properties, our CCS prediction approach demonstrated high accuracy (mean relative error of <3.0%) even when trained with limited data (15 CCS values). Given its ability to excel with limited data, our approach harbors immense potential for constructing a precisely predicted CCS database tailored to each distinct experimental setup. A Python script for CCS prediction using our approach is freely available at https://github.com/MSBSiriraj/SVR_CCSPrediction under the GNU General Public License (GPL) version 3.
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Affiliation(s)
- Pattipong Wisanpitayakorn
- Siriraj
Center of Research Excellence in Metabolomics and Systems Biology
(SiCORE-MSB), Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Siriraj
Metabolomics and Phenomics Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Sitanan Sartyoungkul
- Siriraj
Center of Research Excellence in Metabolomics and Systems Biology
(SiCORE-MSB), Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Siriraj
Metabolomics and Phenomics Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Alongkorn Kurilung
- Siriraj
Center of Research Excellence in Metabolomics and Systems Biology
(SiCORE-MSB), Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Siriraj
Metabolomics and Phenomics Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Yongyut Sirivatanauksorn
- Siriraj
Center of Research Excellence in Metabolomics and Systems Biology
(SiCORE-MSB), Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Siriraj
Metabolomics and Phenomics Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Wonnop Visessanguan
- National
Center for Genetic Engineering and Biotechnology (BIOTEC), Pathumthani 12120, Thailand
| | - Nuankanya Sathirapongsasuti
- Section
of Translational Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand
- Research
Network of NANOTEC - MU Ramathibodi on Nanomedicine, Bangkok 12120, Thailand
| | - Sakda Khoomrung
- Siriraj
Center of Research Excellence in Metabolomics and Systems Biology
(SiCORE-MSB), Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Siriraj
Metabolomics and Phenomics Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Department
of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
- Center
of Excellence for Innovation in Chemistry (PERCH−CIC), Faculty of Science Mahidol University, Bangkok 10400, Thailand
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Omuro S, Yamaguchi T, Kawase T, Terasaki M, Hirose K, Obika S. Physicochemical property evaluation of modified oligonucleotides by traveling-wave ion mobility mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2022; 36:e9279. [PMID: 35203101 DOI: 10.1002/rcm.9279] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 01/27/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
RATIONALE Therapeutic oligonucleotides have molecular weights of more than 6000 Da. They typically contain chemically modified structures such as phosphorothioate (PS) and a locked nucleic acid (LNA). To determine the effect of the length and chemical modification on the physicochemical properties, various nucleic acids with different lengths and modified structures were analyzed using traveling-wave ion mobility mass spectrometry (TWIMS). METHODS The physicochemical characteristics of the modified oligonucleotides were determined using IM-MS. Each oligonucleotide was evaluated by confirming the multivalent charge state drift times, collision cross-section (CCS) values, and CCS widths. RESULTS By plotting the m/z for oligonucleotides of different lengths and the CCS values at each charge state, a bottoming-out shape plot at one charge per 4.0-3.5 bases was confirmed. Moreover, significant differences were observed in the CCS values between the PS-modified and unmodified oligonucleotides. The PS-modified oligonucleotide showed a wider CCS range that was proportional to the PS modification ratio of the oligonucleotide sequence. CONCLUSIONS The TWIMS results showed a correlation between the length and modification of oligonucleotides and the CCS values. In addition, it suggested that each charge state of the oligonucleotide ion has different physicochemical properties.
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Affiliation(s)
- Shogo Omuro
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
| | - Takao Yamaguchi
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
| | | | | | | | - Satoshi Obika
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
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PENG Z, SUN M, LI L, GUO T, MO T, HUANG ZX, GAO W, CHENG P, ZHOU Z. An Improved Design of Electron Ionization Time-of-Fight Mass Spectrometry with Collisional Focusing Ion Guiding. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2021. [DOI: 10.1016/s1872-2040(21)60088-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Endres KJ, Barthelmes K, Winter A, Antolovich R, Schubert US, Wesdemiotis C. Collision cross-section analysis of self-assembled metallomacrocycle isomers and isobars via ion mobility mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34 Suppl 2:e8717. [PMID: 31894612 PMCID: PMC9285404 DOI: 10.1002/rcm.8717] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/20/2019] [Accepted: 12/27/2019] [Indexed: 05/05/2023]
Abstract
RATIONALE Coordinatively driven self-assembly of transition metal ions and bidentate ligands gives rise to organometallic complexes that usually contain superimposed isobars, isomers, and conformers. In this study, the double dispersion ability of ion mobility mass spectrometry (IM-MS) was used to provide a comprehensive structural characterization of the self-assembled supramolecular complexes by their mass and charge, revealed by the MS event, and their shape and collision cross-section (Ω), revealed by the IM event. METHODS Self-assembled complexes were synthesized by reacting a bis(terpyridine) ligand exhibiting a 60o dihedral angle between the two ligating terpyridine sites (T) with divalent Zn, Ni, Cd, or Fe. The products were isolated as (Metal2+ [T])n (PF6 )2n salts and analyzed using IM-MS after electrospray ionization (ESI) which produced several charge states from each n-mer, depending on the number of PF6 - anions lost upon ESI. Experimental Ω data, derived using IM-MS, and computational Ω predictions were used to elucidate the size and architecture of the complexes. RESULTS Only macrocyclic dimers, trimers, and tetramers were observed with Cd2+ , whereas Zn2+ formed the same plus hexameric complexes. These two metals led to the simplest product distributions and no linear isomers. In sharp contrast, Ni2+ and Fe2+ formed all possible ring sizes from dimer to hexamer as well as various linear isomers. The experimental and theoretical Ω data indicated rather planar macrocyclic geometries for the dimers and trimers, twisted 3D architectures for the larger rings, and substantially larger sizes with spiral conformation for the linear congeners. Adding PF6 - to the same complex was found to mainly cause size contraction due to new stabilizing anion-cation interactions. CONCLUSIONS Complete structural identification could be accomplished using ESI-IM-MS. Our results affirm that self-assembly with Cd2+ and Zn2+ proceeds through reversible equilibria that generate the thermodynamically most stable structures, encompassing exclusively macrocyclic architectures that readily accommodate the 60o ligand used. In contrast, complexation with Ni2+ and Fe2+ , which form stronger coordinative bonds, proceeds through kinetic control, leading to more complex mixtures and kinetically trapped less stable architectures, such as macrocyclic pentamers and linear isomers.
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Affiliation(s)
| | - Kevin Barthelmes
- Laboratory of Organic and Macromolecular Chemistry (IOMC)Friedrich Schiller University JenaHumboldtstr. 10JenaGermany
- Department of Materials and Applied ChemistryNihon University1‐8‐14 Kanda SurugadaiChiyoda‐kuTokyoJapan
| | - Andreas Winter
- Laboratory of Organic and Macromolecular Chemistry (IOMC)Friedrich Schiller University JenaHumboldtstr. 10JenaGermany
- Jena Center for Soft Matter (JCSM)Friedrich Schiller Universität JenaPhilosophenweg 7JenaGermany
| | | | - Ulrich S. Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC)Friedrich Schiller University JenaHumboldtstr. 10JenaGermany
- Jena Center for Soft Matter (JCSM)Friedrich Schiller Universität JenaPhilosophenweg 7JenaGermany
| | - Chrys Wesdemiotis
- Department of Polymer ScienceUniversity of AkronAkronOHUSA
- Department of ChemistryUniversity of AkronAkronOHUSA
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Jaafar MHM, Hamid KA. Chitosan-Coated Alginate Nanoparticles Enhanced Absorption Profile of Insulin Via Oral Administration. Curr Drug Deliv 2020; 16:672-686. [PMID: 31250754 DOI: 10.2174/1567201816666190620110748] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 05/10/2019] [Accepted: 05/18/2019] [Indexed: 12/24/2022]
Abstract
BACKGROUND In this study, four nanoparticle formulations (F1 to F4) comprising varying ratios of alginate, Pluronic F-68 and calcium chloride with a constant amount of insulin and chitosan as a coating material were prepared using polyelectrolyte complexation and ionotropic gelation methods to protect insulin against enzymatic degradation. METHODS This study describes the formulation design, optimisation, characterisation and evaluation of insulin concentration via oral delivery in rats. A reversed-phase high-performance liquid chromatography (HPLC) method was developed and validated to quantify insulin concentration in rat plasma. The proposed method produced a linear response over the concentration range of 0.39 to 50 µg/ml. RESULTS In vitro release study showed that dissolution of insulin in simulated gastric juice of pH 1.2 was prevented by alginate core and chitosan coating but rapidly released in simulated intestinal fluid (pH 6.8). Additionally, Formulation 3 (F3) has a particle size of 340.40 ± 2.39 nm with narrow uniformity exhibiting encapsulation efficiency (EE) of 72.78 ± 1.25 % produced highest absorption profile of insulin with a bioavailability of 40.23 ±1.29% and reduced blood glucose after its oral administration in rats. CONCLUSION In conclusion, insulin oral delivery system containing alginate and chitosan as a coating material has the ability to protect the insulin from enzymatic degradation thus enhance its absorption in the intestine. However, more work should be done for instance to involve human study to materialise this delivery system for human use.
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Affiliation(s)
- Mohd H M Jaafar
- Department of Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA, Cawangan Selangor, 42300 Puncak Alam, Malaysia
| | - Khuriah A Hamid
- Department of Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA, Cawangan Selangor, 42300 Puncak Alam, Malaysia
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Bioactive Thymosin Alpha-1 Does Not Influence F508del-CFTR Maturation and Activity. Sci Rep 2019; 9:10310. [PMID: 31311979 PMCID: PMC6635361 DOI: 10.1038/s41598-019-46639-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 07/03/2019] [Indexed: 12/11/2022] Open
Abstract
Deletion of phenylalanine 508 (F508del) in the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel is the most frequent mutation causing cystic fibrosis (CF). F508del-CFTR is misfolded and prematurely degraded. Recently thymosin a-1 (Tα-1) was proposed as a single molecule-based therapy for CF, improving both F508del-CFTR maturation and function by restoring defective autophagy. However, three independent laboratories failed to reproduce these results. Lack of reproducibility has been ascribed by the authors of the original paper to the use of DMSO and to improper handling. Here, we address these potential issues by demonstrating that Tα-1 changes induced by DMSO are fully reversible and that Tα-1 peptides prepared from different stock solutions have equivalent biological activity. Considering the negative results here reported, six independent laboratories failed to demonstrate F508del-CFTR correction by Tα-1. This study also calls into question the autophagy modulator cysteamine, since no rescue of mutant CFTR function was detected following treatment with cysteamine, while deleterious effects were observed when bronchial epithelia were exposed to cysteamine plus the antioxidant food supplement EGCG. Although these studies do not exclude the possibility of beneficial immunomodulatory effects of thymosin α-1, they do not support its utility as a corrector of F508del-CFTR.
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Morris CB, May JC, Leaptrot KL, McLean JA. Evaluating Separation Selectivity and Collision Cross Section Measurement Reproducibility in Helium, Nitrogen, Argon, and Carbon Dioxide Drift Gases for Drift Tube Ion Mobility-Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:1059-1068. [PMID: 30887459 PMCID: PMC6520154 DOI: 10.1007/s13361-019-02151-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/05/2019] [Accepted: 02/06/2019] [Indexed: 05/04/2023]
Abstract
Previous ion mobility (IM) studies have demonstrated that varying the drift gas composition can be used to enhance chemical selectivity and resolution, yet there are few drift gas studies aimed at achieving quantitatively reproducible mobility measurements. Here, we critically evaluate the conditions necessary to achieve reproducible collision cross section (CCS) measurements in pure drift gases (helium, nitrogen, argon, and carbon dioxide) using a commercial uniform field drift tube instrument. Optimal experimental parameters are assessed based on the convergence of CCS measurements to reproducible values which are compared with literature values. A suite of calibration standards with diverse masses, biological classes, and charge states are examined to assess chemical selectivity and resolution achievable in each drift gas. Results indicate nitrogen and argon perform similarly and are sufficient for most applications where high resolving power and high peak capacity are desired. Carbon dioxide exhibits more selectivity for resolving structurally heterogeneous compounds, which may be preferable in specific analyte pair separations. Helium demonstrated modest separation capabilities but has utility for comparison to theoretical values and previously published work. In drift gases other than nitrogen, pressure differentials up to 230 mTorr between the drift tube and upstream chamber were optimal for improving correlation to literature values, while in nitrogen, the recommended pressure differential of 150 mTorr was found appropriate. We present recommended experimental parameters as well as gas-specific CCS measurements for structurally homogeneous sets of analytes which are suitable for use by other laboratories as standards for purposes of instrument calibration and overall assessment of IM separation performance.
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Affiliation(s)
- Caleb B Morris
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | - Jody C May
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | - Katrina L Leaptrot
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | - John A McLean
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA.
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8
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Morris CB, May JC, Leaptrot KL, McLean JA. Evaluating Separation Selectivity and Collision Cross Section Measurement Reproducibility in Helium, Nitrogen, Argon, and Carbon Dioxide Drift Gases for Drift Tube Ion Mobility-Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:1059-1068. [PMID: 30887459 DOI: 10.1021/jasms.8b06014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/05/2019] [Accepted: 02/06/2019] [Indexed: 05/18/2023]
Abstract
Previous ion mobility (IM) studies have demonstrated that varying the drift gas composition can be used to enhance chemical selectivity and resolution, yet there are few drift gas studies aimed at achieving quantitatively reproducible mobility measurements. Here, we critically evaluate the conditions necessary to achieve reproducible collision cross section (CCS) measurements in pure drift gases (helium, nitrogen, argon, and carbon dioxide) using a commercial uniform field drift tube instrument. Optimal experimental parameters are assessed based on the convergence of CCS measurements to reproducible values which are compared with literature values. A suite of calibration standards with diverse masses, biological classes, and charge states are examined to assess chemical selectivity and resolution achievable in each drift gas. Results indicate nitrogen and argon perform similarly and are sufficient for most applications where high resolving power and high peak capacity are desired. Carbon dioxide exhibits more selectivity for resolving structurally heterogeneous compounds, which may be preferable in specific analyte pair separations. Helium demonstrated modest separation capabilities but has utility for comparison to theoretical values and previously published work. In drift gases other than nitrogen, pressure differentials up to 230 mTorr between the drift tube and upstream chamber were optimal for improving correlation to literature values, while in nitrogen, the recommended pressure differential of 150 mTorr was found appropriate. We present recommended experimental parameters as well as gas-specific CCS measurements for structurally homogeneous sets of analytes which are suitable for use by other laboratories as standards for purposes of instrument calibration and overall assessment of IM separation performance.
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Affiliation(s)
- Caleb B Morris
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | - Jody C May
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | - Katrina L Leaptrot
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | - John A McLean
- Center for Innovative Technology, Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA.
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Ouyang H, Bo T, Zhang Z, Guo X, He M, Li J, Yang S, Ma X, Feng Y. Ion mobility mass spectrometry with molecular modelling to reveal bioactive isomer conformations and underlying relationship with isomerization. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2018; 32:1931-1940. [PMID: 30151930 DOI: 10.1002/rcm.8271] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 07/21/2018] [Accepted: 08/20/2018] [Indexed: 06/08/2023]
Abstract
RATIONALE In medicine and drug development, molecular modelling is an important tool. It is attractive to develop a platform connecting the theoretical structural modelling and the results from experimental measurement. In addition, the separation and structural analysis of bioactive constituent isomers are still challenging tasks. METHODS Drift tube ion mobility (IM) mass spectrometry (MS) provides the experimental collision cross section (CCS) which contains the structural information. The experimental CCS can be compared with the calculated CCS of the molecular modelling structures. This technique is especially useful for bioactive constituents in herbal medicine because active isomers with the same chemical formula are common in these samples. IM helps separate and identify these isomers and reveals details about their structures and conformations. RESULTS Two model bioactive constituents, caffeoylquinic acids (CQAs) and dicaffeoylquinic acids (di-CQAs), were selected to systematically investigate the influence of solution, ion source conditions and ion heating on the isomer CCS distributions. By comparing the calculated CCS with the experimental value, we identified the favorable conformations of CQAs. The most compact conformation of a CQA was less likely to isomerize than the more extended conformation. It was found that the isomerization tendency was in accord with the conformation favorability. CONCLUSIONS This study offers an effective approach to predict and demystify the conformation and isomerization of the active constituents in herbal medicines.
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Affiliation(s)
- Hui Ouyang
- Jiangxi University of Traditional Chinese Medicine, No. 818 Yunwan Road, Nanchang, 330002, China
| | - Tao Bo
- Agilent Technologies, No. 3, Wang Jing Bei Lu, Beijing, 100102, China
| | - Zhengxiang Zhang
- Agilent Technologies, No. 3, Wang Jing Bei Lu, Beijing, 100102, China
| | - Xinqiu Guo
- Ming De Tian Sheng Biotech Inc., Changping Campus of Peking University, Beijing, 102200, China
| | - Mingzhen He
- Jiangxi University of Traditional Chinese Medicine, No. 818 Yunwan Road, Nanchang, 330002, China
| | - Junmao Li
- Jiangxi University of Traditional Chinese Medicine, No. 818 Yunwan Road, Nanchang, 330002, China
| | - Shilin Yang
- Jiangxi University of Traditional Chinese Medicine, No. 818 Yunwan Road, Nanchang, 330002, China
- State Key Laboratory of Innovative Drug and Efficient Energy-Saving Pharmaceutical Equipment, No. 56 Yangming Road, Nanchang, 330006, China
| | - Xin Ma
- Agilent Technologies, No. 3, Wang Jing Bei Lu, Beijing, 100102, China
| | - Yulin Feng
- Jiangxi University of Traditional Chinese Medicine, No. 818 Yunwan Road, Nanchang, 330002, China
- State Key Laboratory of Innovative Drug and Efficient Energy-Saving Pharmaceutical Equipment, No. 56 Yangming Road, Nanchang, 330006, China
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10
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May JC, Jurneczko E, Stow SM, Kratochvil I, Kalkhof S, McLean JA. Conformational Landscapes of Ubiquitin, Cytochrome c, and Myoglobin: Uniform Field Ion Mobility Measurements in Helium and Nitrogen Drift Gas. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2018; 427:79-90. [PMID: 29915518 PMCID: PMC6003721 DOI: 10.1016/j.ijms.2017.09.014] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
In this study, a commercial uniform field drift tube ion mobility-mass spectrometer (IM-MS) was utilized to measure the gas-phase conformational populations of three well-studied proteins: ubiquitin (8566 Da), cytochrome c (12,359 Da), and myoglobin in both apo and holo forms (16,951 and 17,567 Da, respectively) in order to evaluate the use of this technology for broadscale structural proteomics applications. Proteins were electrosprayed from either acidic organic (pH ~3) or aqueous buffered (pH ~6.6) solution phase conditions, which generated a wide range of cation charge states corresponding to both extended (unfolded) and compact (folded) gas-phase conformational populations. Corresponding collision cross section (CCS) measurements were compiled for significant ion mobility peak features observed at each charge state in order to map the conformational landscapes of these proteins in both helium and nitrogen drift gases. It was observed that the conformational landscapes were similar in both drift gases, with differences being attributed primarily to ion heating during helium operation due to the necessity of operating the instrument with higher pressure differentials. Higher resolving powers were observed in nitrogen, which allowed for slightly better structural resolution of closely-spaced conformer populations. The instrumentation was found to be particularly adept at measuring low abundance conformers which are only present under gentle conditions which minimize ion heating. This work represents the single largest ion mobility CCS survey published to date for these three proteins with 266 CCS values and 117 ion mobility spectra, many of which have not been previously reported.
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Affiliation(s)
- Jody C. May
- Department of Chemistry, Center for Innovative Technology, Vanderbilt Institute for Integrative Biosystems Research and Education, and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, 37235, United States
| | - Ewa Jurneczko
- Department of Chemistry, Center for Innovative Technology, Vanderbilt Institute for Integrative Biosystems Research and Education, and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, 37235, United States
| | - Sarah M. Stow
- Department of Chemistry, Center for Innovative Technology, Vanderbilt Institute for Integrative Biosystems Research and Education, and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, 37235, United States
| | - Isabel Kratochvil
- Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, Leipzig University, 04103 Leipzig, Germany
| | - Stefan Kalkhof
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research - UFZ, 04318 Leipzig, Germany
| | - John A. McLean
- Department of Chemistry, Center for Innovative Technology, Vanderbilt Institute for Integrative Biosystems Research and Education, and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, 37235, United States
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Molano-Arevalo JC, Dit Fouque KJ, Pham K, Miksovska J, Ridgeway ME, Park MA, Fernandez-Lima F. Characterization of Intramolecular Interactions of Cytochrome c Using Hydrogen-Deuterium Exchange-Trapped Ion Mobility Spectrometry-Mass Spectrometry and Molecular Dynamics. Anal Chem 2017; 89:8757-8765. [PMID: 28742962 PMCID: PMC5653375 DOI: 10.1021/acs.analchem.7b00844] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Globular proteins, such as cytochrome c (cyt c), display an organized native conformation, maintained by a hydrogen bond interaction network. In the present work, the structural interrogation of kinetically trapped intermediates of cyt c was performed by correlating the ion-neutral collision cross section (CCS) and charge state with the starting solution conditions and time after desolvation using collision induced activation (CIA), time-resolved hydrogen/deuterium back exchange (HDX) and trapped ion mobility spectrometry-mass spectrometry (TIMS-MS). The high ion mobility resolving power of the TIMS analyzer allowed the identification of new ion mobility bands, yielding a total of 63 mobility bands over the +6 to +21 charge states and 20 mobility bands over the -5 to -10 charge states. Mobility selected HDX rates showed that for the same charge state, conformers with larger CCS present faster HDX rates in both positive and negative ion mode, suggesting that the charge sites and neighboring exchange sites on the accessible surface area define the exchange rate regardless of the charge state. Complementary molecular dynamic simulations permitted the generation of candidate structures and a mechanistic model of the folding transitions from native (N) to molten globule (MG) to kinetic intermediates (U) pathways. Our results suggest that cyt c major structural unfolding is associated with the distancing of the N- and C-terminal helices and subsequent solvent exposure of the hydrophobic, heme-containing cavity.
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Affiliation(s)
| | - Kevin Jeanne Dit Fouque
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Khoa Pham
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Jaroslava Miksovska
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199
| | | | - Melvin A. Park
- Bruker Daltonics, Inc., Billerica, Massachusetts, 01821, USA
| | - Francisco Fernandez-Lima
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199
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Haynes SE, Polasky DA, Dixit SM, Majmudar JD, Neeson K, Ruotolo BT, Martin BR. Variable-Velocity Traveling-Wave Ion Mobility Separation Enhancing Peak Capacity for Data-Independent Acquisition Proteomics. Anal Chem 2017; 89:5669-5672. [PMID: 28471653 DOI: 10.1021/acs.analchem.7b00112] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
High mass accuracy, data-dependent acquisition is the current standard method in mass spectrometry-based peptide annotation and quantification. In high complexity samples, limited instrument scan speeds often result in under-sampling. In contrast, all-ion data-independent acquisition methods bypass precursor selection, alternating high and low collision energies to analyze product and precursor ions across wide mass ranges. Despite capturing data for all events, peptide annotation is limited by inadequate alignment algorithms or overlapping ions. Ion mobility separation can add an orthogonal analytical dimension, reducing ion interference to improve reproducibility, peak capacity, and peptide identifications to rival modern hybrid quadrupole orbitrap systems. Despite the advantages of ion mobility separation in complex proteomics analyses, there has been no quantitative measure of ion mobility resolution in a complex proteomic sample. Here, we present TWIMExtract, a data extraction tool to export defined slices of liquid chromatography/ion mobility/mass spectrometry (LC-IM-MS) data, providing a route to quantify ion mobility resolution from a commercial traveling-wave ion mobility time-of-flight mass spectrometer. Using standard traveling-wave ion mobility parameters (600 m/s, 40 V), 90% of the annotated peptides occupied just 23% of the ion mobility drift space, yet inclusion of ion mobility nearly doubled the overall peak capacity. Relative to fixed velocity traveling-wave ion mobility settings, ramping the traveling-wave velocity increased drift space occupancy, amplifying resolution by 16%, peak capacity by nearly 50%, and peptide/protein identifications by 40%. Overall, variable-velocity traveling-wave ion mobility-mass spectrometry significantly enhances proteomics analysis in all-ion fragmentation acquisition.
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Affiliation(s)
- Sarah E Haynes
- Department of Chemistry, University of Michigan , 930 N. University Ave., Ann Arbor, Michigan 48109, United States
| | - Daniel A Polasky
- Department of Chemistry, University of Michigan , 930 N. University Ave., Ann Arbor, Michigan 48109, United States
| | - Sugyan M Dixit
- Department of Chemistry, University of Michigan , 930 N. University Ave., Ann Arbor, Michigan 48109, United States
| | - Jaimeen D Majmudar
- Department of Chemistry, University of Michigan , 930 N. University Ave., Ann Arbor, Michigan 48109, United States
| | - Kieran Neeson
- Waters Corporation , Stamford Avenue, Altrincham Road, Wilmslow, SK9 4AX, United Kingdom
| | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan , 930 N. University Ave., Ann Arbor, Michigan 48109, United States
| | - Brent R Martin
- Department of Chemistry, University of Michigan , 930 N. University Ave., Ann Arbor, Michigan 48109, United States
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13
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Abstract
In this review, we focus on an important aspect of ion mobility (IM) research, namely the reporting of quantitative ion mobility measurements in the form of the gas-phase collision cross section (CCS), which has provided a common basis for comparison across different instrument platforms and offers a unique form of structural information, namely size and shape preferences of analytes in the absence of bulk solvent. This review surveys the over 24,000 CCS values reported from IM methods spanning the era between 1975 to 2015, which provides both a historical and analytical context for the contributions made thus far, as well as insight into the future directions that quantitative ion mobility measurements will have in the analytical sciences. The analysis was conducted in 2016, so CCS values reported in that year are purposely omitted. In another few years, a review of this scope will be intractable, as the number of CCS values which will be reported in the next three to five years is expected to exceed the total amount currently published in the literature.
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Affiliation(s)
- Jody C May
- Department of Chemistry, Center for Innovative Technology, Vanderbilt Institute for Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt University , Nashville, Tennessee 37235, United States
| | - Caleb B Morris
- Department of Chemistry, Center for Innovative Technology, Vanderbilt Institute for Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt University , Nashville, Tennessee 37235, United States
| | - John A McLean
- Department of Chemistry, Center for Innovative Technology, Vanderbilt Institute for Chemical Biology, Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt University , Nashville, Tennessee 37235, United States
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14
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Basiri B, van Hattum H, van Dongen WD, Murph MM, Bartlett MG. The Role of Fluorinated Alcohols as Mobile Phase Modifiers for LC-MS Analysis of Oligonucleotides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:190-199. [PMID: 27644940 PMCID: PMC5500909 DOI: 10.1007/s13361-016-1500-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 06/06/2023]
Abstract
Hexafluoroisopropanol (HFIP) has been widely used as an acidic modifier for mobile phases for liquid chromatography-mass spectrometry (LC-MS) analysis of oligonucleotides ever since the first report of its use for this purpose. This is not surprising, considering the exceptional performance of HFIP compared with carboxylic acids, which cause significant MS signal suppression in electrospray ionization. However, we have found that other fluorinated alcohols can also be utilized for mobile phase preparation and the choice of optimal fluorinated alcohol is determined by the ion-pairing (IP) agent. Although HFIP is a very good choice to be used alongside less hydrophobic IP agents, other fluorinated alcohols such as 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol (HFMIP) can significantly outperform HFIP when used with more hydrophobic IP agents. We also found that more acidic fluorinated alcohols assist with the transfer of oligonucleotides with secondary structure (e.g., folded strands and hairpins) into the gas phase. Graphical Abstract ᅟ.
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Affiliation(s)
- Babak Basiri
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 W. Green Street, Athens, GA, 30602-2352, USA
| | - Hilde van Hattum
- ProQR Therapeutics NV, Zernikedreef 9, 2333 CK, Leiden, The Netherlands
| | | | - Mandi M Murph
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 W. Green Street, Athens, GA, 30602-2352, USA
| | - Michael G Bartlett
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 W. Green Street, Athens, GA, 30602-2352, USA.
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15
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Coordination-Driven, Self-Assembly of a Polycyclic, Terpyridine-Based Nanobelt. J Inorg Organomet Polym Mater 2016. [DOI: 10.1007/s10904-016-0393-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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16
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Isomer Separation of Polybrominated Diphenyl Ether Metabolites using nanoESI-TIMS-MS. ACTA ACUST UNITED AC 2016; 19:69-76. [PMID: 27642261 DOI: 10.1007/s12127-016-0198-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
In this paper, high-resolution nano-electrospray ionization-trapped ion mobility spectrometry coupled to mass spectrometry (nESI-TIMS-MS) is used for the study of hydroxylated polybrominated diphenyl ether (OH-PBDE) metabolites. In particular, experimental ion-neutral collision cross sections (CCS) were measured for five structural OH-PBDE isomers using TIMS-MS. Candidate structures were proposed for each IMS band observed in good agreement with the experimental CCS measurements (5% error). The analytical power of TIMS-MS to baseline and partially separate structural isomers of OH-BDE in binary and ternary mixtures is shown for single charge species with a mobility resolving power of RIMS ~ 400. This work provides the proof of concept for the analysis of low concentration OH-PBDE in environmental samples based on accurate collision cross section and mass measurements without the need for derivatization and pre-fractionation protocols, thus significantly reducing the cost and analysis time.
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17
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May JC, McLean JA. A uniform field ion mobility study of melittin and implications of low-field mobility for resolving fine cross-sectional detail in peptide and protein experiments. Proteomics 2015; 15:2862-71. [DOI: 10.1002/pmic.201400551] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 03/04/2015] [Accepted: 04/14/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Jody C. May
- Department of Chemistry, Center for Innovative Technology; Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt Institute of Chemical Biology; Vanderbilt University; Nashville TN USA
| | - John A. McLean
- Department of Chemistry, Center for Innovative Technology; Vanderbilt Institute for Integrative Biosystems Research and Education, Vanderbilt Institute of Chemical Biology; Vanderbilt University; Nashville TN USA
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18
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Schenk ER, Nau F, Fernandez-Lima F. Theoretical predictor for candidate structure assignment from IMS data of biomolecule-related conformational space. INTERNATIONAL JOURNAL FOR ION MOBILITY SPECTROMETRY : OFFICIAL PUBLICATION OF THE INTERNATIONAL SOCIETY FOR ION MOBILITY SPECTROMETRY 2015; 18:23-29. [PMID: 27330407 PMCID: PMC4909055 DOI: 10.1007/s12127-015-0165-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The ability to correlate experimental ion mobility data with candidate structures from theoretical modeling provides a powerful analytical and structural tool for the characterization of biomolecules. In the present paper, a theoretical workflow is described to generate and assign candidate structures for experimental trapped ion mobility and H/D exchange (HDX-TIMS-MS) data following molecular dynamics simulations and statistical filtering. The applicability of the theoretical predictor is illustrated for a peptide and protein example with multiple conformations and kinetic intermediates. The described methodology yields a low computational cost and a simple workflow by incorporating statistical filtering and molecular dynamics simulations. The workflow can be adapted to different IMS scenarios and CCS calculators for a more accurate description of the IMS experimental conditions. For the case of the HDX-TIMS-MS experiments, molecular dynamics in the "TIMS box" accounts for a better sampling of the molecular intermediates and local energy minima.
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Affiliation(s)
- Emily R Schenk
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Frederic Nau
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Francisco Fernandez-Lima
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
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19
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Schenk ER, Almeida R, Miksovska J, Ridgeway ME, Park MA, Fernandez-Lima F. Kinetic intermediates of holo- and apo-myoglobin studied using HDX-TIMS-MS and molecular dynamic simulations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:555-63. [PMID: 25690175 PMCID: PMC4402236 DOI: 10.1007/s13361-014-1067-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/01/2014] [Accepted: 12/07/2014] [Indexed: 05/05/2023]
Abstract
In the present work, the kinetic intermediates of holo- and apo-myoglobin were studied by correlating the ion-neutral collision cross section and time resolved H/D back exchange rate simultaneously in a trapped ion mobility spectrometer coupled to a mass spectrometer (HDX-TIMS-MS). The high mobility resolution of the TIMS cell permitted the observation of multiple IMS bands and complementary molecular dynamics simulations resulted in the assignment of candidate structures for each experimental condition studied (e.g., holo [M + 8H](+8)-[M + 9H](+9) and apo [M + 9H](+9)-[M + 19H](+19)). Inspection of the kinetic intermediates suggests that the tertiary structure of apomyoglobin unfolds quickly upon the loss of the Fe protoporphyrin IX that stabilizes the interactions between the A, G, and H helices. In the absence of the porphyrin heme, the apomyoglobin unfolds to Xn kinetic intermediates that vary in the extent of unfolding as a result of the observed charge state.
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Affiliation(s)
- Emily R. Schenk
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Raybel Almeida
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Jaroslava Miksovska
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | | | | | - Francisco Fernandez-Lima
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
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20
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Molano-Arevalo JC, Hernandez DR, Gonzalez WG, Miksovska J, Ridgeway ME, Park MA, Fernandez-Lima F. Flavin adenine dinucleotide structural motifs: from solution to gas phase. Anal Chem 2014; 86:10223-30. [PMID: 25222439 PMCID: PMC4204916 DOI: 10.1021/ac5023666] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
![]()
Flavin
adenine dinucleotide (FAD) is involved in important metabolic
reactions where the biological function is intrinsically related to
changes in conformation. In the present work, FAD conformational changes
were studied in solution and in gas phase by measuring the fluorescence
decay time and ion-neutral collision cross sections (CCS, in a trapped
ion mobility spectrometer, TIMS) as a function of the solvent conditions
(i.e., organic content) and gas-phase collisional partner (i.e., N2 doped with organic molecules). Changes in the fluorescence
decay suggest that FAD can exist in four conformations in solution,
where the abundance of the extended conformations increases with the
organic content. TIMS-MS experiments showed that FAD can exist in
the gas phase as deprotonated (M = C27H31N9O15P2) and protonated forms (M = C27H33N9O15P2) and
that multiple conformations (up to 12) can be observed as a function
of the starting solution for the [M + H]+ and [M + Na]+molecular ions. In addition, changes in the relative abundances
of the gas-phase structures were observed from a “stack”
to a “close” conformation when organic molecules were
introduced in the TIMS cell as collision partners. Candidate structures
optimized at the DFT/B3LYP/6-31G(d,p) were proposed for each IMS band,
and results showed that the most abundant IMS band corresponds to
the most stable candidate structure. Solution and gas-phase experiments
suggest that the driving force that stabilizes the different conformations
is based on the interaction of the adenine and isoalloxazine rings
that can be tailored by the “solvation” effect created
with the organic molecules.
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Affiliation(s)
- Juan Camilo Molano-Arevalo
- Department of Chemistry and Biochemistry, Florida International University , Miami, Florida 33199, United States
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21
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Hernandez DR, DeBord JD, Ridgeway ME, Kaplan DA, Park MA, Fernandez-Lima F. Ion dynamics in a trapped ion mobility spectrometer. Analyst 2014; 139:1913-21. [PMID: 24571000 PMCID: PMC4144823 DOI: 10.1039/c3an02174b] [Citation(s) in RCA: 187] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In the present paper, theoretical simulations and experimental observations are used to describe the ion dynamics in a trapped ion mobility spectrometer. In particular, the ion motion, ion transmission and mobility separation are discussed as a function of the bath gas velocity, radial confinement, analysis time and speed. Mobility analysis and calibration procedure are reported for the case of sphere-like molecules for positive and negative ion modes. Results showed that a maximal mobility resolution can be achieved by optimizing the gas velocity, radial confinement (RF amplitude) and ramp speed (voltage range and ramp time). The mobility resolution scales with the electric field and gas velocity and R = 100-250 can be routinely obtained at room temperature.
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Affiliation(s)
- Diana Rosa Hernandez
- Department of Chemistry and Biochemistry, Florida International University, Miami, USA. ; Fax: +1 305 348 3772; Tel: +1 305 348 2037
| | - John Daniel DeBord
- Department of Chemistry and Biochemistry, Florida International University, Miami, USA. ; Fax: +1 305 348 3772; Tel: +1 305 348 2037
| | | | | | - Melvin A. Park
- Bruker Daltonics, Inc., Billerica, Massachusetts 01821, USA
| | - Francisco Fernandez-Lima
- Department of Chemistry and Biochemistry, Florida International University, Miami, USA. ; Fax: +1 305 348 3772; Tel: +1 305 348 2037
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22
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Ma X, Zhou M, Wysocki VH. Surface induced dissociation yields quaternary substructure of refractory noncovalent phosphorylase B and glutamate dehydrogenase complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:368-379. [PMID: 24452296 DOI: 10.1007/s13361-013-0790-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 11/11/2013] [Accepted: 11/19/2013] [Indexed: 06/03/2023]
Abstract
Ion mobility (IM) and tandem mass spectrometry (MS/MS) coupled with native MS are useful for studying noncovalent protein complexes. Collision induced dissociation (CID) is the most common MS/MS dissociation method. However, some protein complexes, including glycogen phosphorylase B kinase (PHB) and L-glutamate dehydrogenase (GDH) examined in this study, are resistant to dissociation by CID at the maximum collision energy available in the instrument. Surface induced dissociation (SID) was applied to dissociate the two refractory protein complexes. Different charge state precursor ions of the two complexes were examined by CID and SID. The PHB dimer was successfully dissociated to monomers and the GDH hexamer formed trimeric subcomplexes that are informative of its quaternary structure. The unfolding of the precursor and the percentages of the distinct products suggest that the dissociation pathways vary for different charge states. The precursors at lower charge states (+21 for PHB dimer and +27 for GDH hexamer) produce a higher percentage of folded fragments and dissociate more symmetrically than the precusors at higher charge states (+29 for PHB dimer and +39 for GDH hexamer). The precursors at lower charge state may be more native-like than the higher charge state because a higher percentage of folded fragments and a lower percentage of highly charged unfolded fragments are detected. The combination of SID and charge reduction is shown to be a powerful tool for quaternary structure analysis of refractory noncovalent protein complexes, as illustrated by the data for PHB dimer and GDH hexamer.
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Affiliation(s)
- Xin Ma
- Department of Chemistry and Biochemistry, The Ohio State University, 876 Biological Sciences Building, 484 W 12th Ave, Columbus, OH, 43210, USA
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23
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Schenk E, Mendez V, Landrum JT, Ridgeway ME, Park MA, Fernandez-Lima F. Direct observation of differences of carotenoid polyene chain cis/trans isomers resulting from structural topology. Anal Chem 2014; 86:2019-24. [PMID: 24428664 PMCID: PMC3983025 DOI: 10.1021/ac403153m] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 01/15/2014] [Indexed: 02/07/2023]
Abstract
In the present paper, trapped ion mobility spectrometry (TIMS) and theoretical calculations have been used to study carotenoid geometrical motifs generated by photoisomerization from the all-trans geometry. Multiple geometric isomers of the carotenoids lutein and zeaxanthin were separated using TIMS (R > 110) for [M](+), [M + H](+), and [M - 18](+) molecular species. Comparison of observed cross sections with those obtained from molecular dynamics calculations showed that the number of cis double bonds and s-cis single bonds in the polyene chain determine the topology space of the carotenoid. The intensities of IMS signals are correlated with the relative stability of these geometric isomers.1,2 The most stable isomer is the all-trans geometry regardless of the ionization state ([M - 18](+), [M](+), and [M + H](+)), and structural stability decreases with the increasing number of cis and/or s-cis bonds in the polyene chain.
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Affiliation(s)
- Emily
R. Schenk
- Department
of Chemistry and Biochemistry, Florida International
University, Miami, FL 33199, U.S.A.
| | - Vanesa Mendez
- Department
of Chemistry and Biochemistry, Florida International
University, Miami, FL 33199, U.S.A.
| | - John T. Landrum
- Department
of Chemistry and Biochemistry, Florida International
University, Miami, FL 33199, U.S.A.
| | | | - Melvin A. Park
- Bruker
Daltonics,
Inc., Billerica, Massachusetts 01821, USA
| | - Francisco Fernandez-Lima
- Department
of Chemistry and Biochemistry, Florida International
University, Miami, FL 33199, U.S.A.
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24
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Schenk ER, Ridgeway ME, Park MA, Leng F, Fernandez-Lima F. Isomerization kinetics of AT hook decapeptide solution structures. Anal Chem 2014; 86:1210-4. [PMID: 24364733 PMCID: PMC3935383 DOI: 10.1021/ac403386q] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The mammalian high mobility group protein HMGA2 contains three DNA binding motifs associated with many physiological functions including oncogenesis, obesity, stem cell youth, human height, and human intelligence. In the present paper, trapped ion mobility spectrometry-mass spectrometry (TIMS-MS) has been utilized to study the conformational dynamics of the third DNA binding motif using the "AT hook" decapeptide unit (Lys(1)-Arg(2)-Prol(3)-Arg(4)-Gly(5)-Arg(6)-Prol(7)-Arg(8)-Lys(9)-Trp(10), ATHP) as a function of the solvent state. Solvent state distributions were preserved during electrospray ion formation, and multiple IMS bands were identified for the [M + 2H](2+) and for the [M + 3H](3+) charge states. Conformational isomer interconversion rates were measured as a function of the trapping time for the [M + 2H](2+) and [M + 3H](3+) charge states. Candidate structures were proposed for all IMS bands observed. Protonation site, proline residue conformation, and side chain orientations were identified as the main motifs governing the conformational interconversion processes. Conformational dynamics from the solvent state distribution to the gas-phase "de-solvated" state distribution demonstrated that ATHP is "structured", and relative abundances are associated with the relative stability between the proposed conformers. The most stable ATHP [M + 2H](2+) conformation at the "de-solvated" state corresponds to the AT hook motif observed in AT-rich DNA regions.
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Affiliation(s)
- Emily R. Schenk
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | | | - Melvin A. Park
- Bruker Daltonics, Inc., Billerica, Massachusetts 01821, USA
| | - Fenfei Leng
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Francisco Fernandez-Lima
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
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25
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Hieke A. Suppression of unimolecular decay of laser desorbed peptide and protein ions by entrainment in rarefied supersonic gas jets under weak electric fields. J Chem Phys 2014; 140:034201. [PMID: 25669372 DOI: 10.1063/1.4861040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Unimolecular decay of sample ions imposes a limit on the usable laser fluence in matrix-assisted laser desorption/ionization (MALDI) ion sources. Traditionally, some modest degree of collisional sample ion cooling has been achieved by connecting MALDI ion sources directly to gas-filled radio frequency (RF) multipoles. It was also discovered in the early 1990s that gas-filled RF multipoles exhibit increased ion transmission efficiency due to collisional ion focusing effects. This unexpected experimental finding was later supported by elementary Monte Carlo simulations. Both experiments and simulations assumed a resting background gas with typical pressures of the order of 1 Pa. However, considerable additional improvements can be achieved if laser desorbed sample ions are introduced immediately after desorption, still within the ion source, in an axisymmetric rarefied supersonic gas jet with peak pressure of the order of 100 Pa and flow velocities >300 m/s, and under weak electric fields. We describe here the design principle and report performance data of an ion source coined "MALDI-2," which incorporates elements of both rarefied aerodynamics and particle optics. Such a design allows superb suppression of metastable fragmentation due to rapid collisional cooling in <10 μs and nearly perfect injection efficiency into the attached RF ion guide, as numerous experiments have confirmed.
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Affiliation(s)
- Andreas Hieke
- Department of Structural Biology, School of Medicine, Stanford University, 299 Campus Drive West, Fairchild Building, 148, Stanford, California 94305-5126, USA
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26
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He M, Guo D, Chen Y, Xiong X, Fang X, Xu W. Ion collision crosssection measurements in quadrupole ion traps using a time–frequency analysis method. Analyst 2014; 139:6144-53. [DOI: 10.1039/c4an01216j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this study, a method for measuring ion collision crosssections (CCSs) was proposed through time–frequency analysis of ion trajectories in quadrupole ion traps.
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Affiliation(s)
- Muyi He
- School of Life Sciences
- Beijing Institute of Technology
- Beijing 100081, China
| | - Dan Guo
- School of Life Sciences
- Beijing Institute of Technology
- Beijing 100081, China
| | - Yu Chen
- Shanxi Cancer Hospital
- Xian, Shanxi 710061, China
| | | | - Xiang Fang
- National Institute of Metrology
- Beijing 100013, China
| | - Wei Xu
- School of Life Sciences
- Beijing Institute of Technology
- Beijing 100081, China
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27
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Ma X, Shah S, Zhou M, Park CK, Wysocki VH, Horton NC. Structural analysis of activated SgrAI-DNA oligomers using ion mobility mass spectrometry. Biochemistry 2013; 52:4373-81. [PMID: 23742104 DOI: 10.1021/bi3013214] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
SgrAI is a type IIF restriction endonuclease that cuts an unusually long recognition sequence and exhibits self-modulation of DNA cleavage activity and sequence specificity. Previous studies have shown that SgrAI forms large oligomers when bound to particular DNA sequences and under the same conditions where SgrAI exhibits accelerated DNA cleavage kinetics. However, the detailed structure and stoichiometry of the SgrAI-DNA complex as well as the basic building block of the oligomers have not been fully characterized. Ion mobility mass spectrometry (IM-MS) was employed to analyze SgrAI-DNA complexes and show that the basic building block of the oligomers is the DNA-bound SgrAI dimer (DBD) with one SgrAI dimer bound to two precleaved duplex DNA molecules each containing one-half of the SgrAI primary recognition sequence. The oligomers contain variable numbers of DBDs with as many as 19 DBDs. Observation of the large oligomers shows that nanoelectrospray ionization (nano-ESI) can preserve the proposed activated form of an enzyme. Finally, the collision cross section of the SgrAI-DNA oligomers measured by IM-MS was found to have a linear relationship with the number of DBDs in each oligomer, suggesting a regular, repeating structure.
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Affiliation(s)
- Xin Ma
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
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28
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Li S, Jia J, Gao X, He X, Li J. Analysis of antibiotics from liquid sample using electrospray ionization-ion mobility spectrometry. Anal Chim Acta 2012; 720:97-103. [DOI: 10.1016/j.aca.2012.01.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 01/04/2012] [Accepted: 01/06/2012] [Indexed: 10/14/2022]
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Fernandez-Lima FA, Nascimento MAC, da Silveira EF. Alkali halide clusters produced by fast ion impact. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION B, BEAM INTERACTIONS WITH MATERIALS AND ATOMS 2012; 273:102-104. [PMID: 22389542 PMCID: PMC3290408 DOI: 10.1016/j.nimb.2011.07.050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The most abundant geometries and relative stabilities of alkali halide clusters with a (XY)(n) (o) configuration (e.g., LiF, NaCl, KBr) are described. Five main series were obtained: linear, cyclic, cubic, arc strips and nanotubes. The stability analysis shows that higher members are likely to be formed from the lower member of the same series and/or from two building blocks (n = 1, 2). The energy analysis (D-plot) indicates that the most compact ones (e.g., cubic and nanotubes) present higher stability when compared to the linear, cyclic and arc strip structures; moreover, relative stability between the cubic and nanotube series varies with the cluster size.
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Scionti V, Katzenmeyer BC, Solak N, Li X, Wesdemiotis C. Interfacing multistage mass spectrometry with liquid chromatography or ion mobility separation for synthetic polymer analysis. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2012; 18:113-137. [PMID: 22641724 DOI: 10.1255/ejms.1175] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Synthetic polymers are naturally mixtures of homologs, even in pure form. More complexity is introduced by the presence of different comonomers, end groups and/or macromolecular architectures. The analysis of such systems is substantially facilitated by interfacing mass spectrometry (MS), which disperses based on mass, with an additional level of separation involving either interactive liquid chromatography (LC) or ion mobility (IM) spectrometry, both of which are readily coupled online with electrospray ionization and MS detection. IM-MS separates in the gas phase, post-ionization and, therefore, is ideally suitable for labile and reactive polymers. Its usefulness is illustrated with the characterization of non-covalent siloxane-saccharide complexes, metallosupramolecular assemblies and an air- and moisture-sensitive inorganic polymer, poly(dichlorophosphazene). Conversely, LC-MS which separates in solution phase, before ionization, is most effective for the analysis of polymeric mixtures whose components differ in polarity. Interactive LC conditions can be optimized to disperse by the content of hydrophobic units, as is demonstrated for amphiphilic polyether copolymers and sugar-based nonionic surfactant blends. Both LC-MS and IM-MS can be extended into a third dimension by tandem mass spectrometry (MS(2)) studies on select oligomers, in order to obtain insight into individual end groups and isomeric architectures, comonomer sequences and degree of substitution, for example, by hydrophobic functionalities.
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Affiliation(s)
- Vincenzo Scionti
- Department of Chemistry, The University of Akron, Akron, OH 44325, USA
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Chan YT, Li X, Yu J, Carri GA, Moorefield CN, Newkome GR, Wesdemiotis C. Design, synthesis, and traveling wave ion mobility mass spectrometry characterization of iron(II)- and ruthenium(II)-terpyridine metallomacrocycles. J Am Chem Soc 2011; 133:11967-76. [PMID: 21718066 DOI: 10.1021/ja107307u] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
New metallomacrocycles composed of 2,2':6',2″-terpyridine (tpy) ligands and Ru(II) or Fe(II) transition metal ions were prepared by stepwise directed assembly and characterized by 2D diffusion NMR spectroscopy (DOSY), electrospray ionization traveling wave ion mobility mass spectrometry (ESI TWIM MS), and molecular modeling. The supramolecular polymers synthesized include a homonuclear all-Ru hexamer as well as heteronuclear hexamer and nonamer with alternating Ru/Ru/Fe metal centers. ESI MS yields several charge states from each supramacromolecule. If ESI is interfaced with TWIM MS, overlapping charge states and the isomeric components of an individual charge state are separated based on their unique drift times through the TWIM region. From experimentally measured drift times, collision cross-sections can be deduced. The collision cross-sections obtained for the synthesized supramacromolecules are in good agreement with those predicted by molecular modeling for macrocyclic structures. Similarly, the hydrodynamic radii of the synthesized complexes derived from 2D DOSY NMR experiments agree excellently with the radii calculated for macrocyclic architectures, confirming the ESI TWIM MS finding. ESI TWIM MS and 2D DOSY NMR spectroscopy provide an alternative approach for the structural analysis of supramolecules that are difficult or impossible to crystallize, such as the large macrocyclic assemblies investigated. ESI TWIM MS will be particularly valuable for the characterization of supramolecular assemblies not available in the quantity or purity required for NMR studies.
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Affiliation(s)
- Yi-Tsu Chan
- Departments of Polymer Science, The University of Akron, Akron, Ohio, 44325, USA
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Fernandez-Lima F, Kaplan DA, Suetering J, Park MA. Gas-phase separation using a trapped ion mobility spectrometer. ACTA ACUST UNITED AC 2011; 14. [PMID: 24163587 DOI: 10.1007/s12127-011-0067-8] [Citation(s) in RCA: 212] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In the present work we describe the principles of operation, versatility and applicability of a trapped ion mobility spectrometer (TIMS) analyzer for fast, gas-phase separation of molecular ions based on their size-to-charge ratio. Mobility-based separation using a TIMS device is shown for a series for isobar pairs. In a TIMS device, mobility resolution depends on the bath gas velocity and analysis scan speed, with the particularity that the mobility separation can be easily tuned from low to high resolution (R>50) in accordance with the analytical challenge. In contrast to traditional drift tube IMS analyzer, a TIMS device can be easily integrated in a mass spectrometer without a noticeable loss in ion transmission or sensitivity, thus providing a powerful separation platform prior to mass analysis.
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Wang JL, Li X, Lu X, Chan YT, Moorefield CN, Wesdemiotis C, Newkome GR. Dendron-Functionalized Bis(terpyridine)-Iron(II) or -Cadmium(II) Metallomacrocycles: Synthesis, Traveling-Wave Ion-Mobility Mass Spectrometry, and Photophysical Properties. Chemistry 2011; 17:4830-8. [DOI: 10.1002/chem.201003681] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Indexed: 11/10/2022]
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Hogan CJ, de la Mora JF. Ion mobility measurements of nondenatured 12-150 kDa proteins and protein multimers by tandem differential mobility analysis-mass spectrometry (DMA-MS). JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2011; 22:158-172. [PMID: 21472554 DOI: 10.1007/s13361-010-0014-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 10/04/2010] [Accepted: 10/06/2010] [Indexed: 05/30/2023]
Abstract
The mobilities of electrosprayed proteins and protein multimers with molecular weights ranging from 12.4 kDa (cytochrome C monomers) to 154 kDa (nonspecific concanavalin A hexamers) were measured in dry air by a planar differential mobility analyzer (DMA) coupled to a time-of-flight mass spectrometer (TOF-MS). The DMA determines true mobility at atmospheric pressure, without perturbing ion structure from that delivered by the electrospray. A nondenaturing aqueous 20 mM triethylammonium formate buffer yields compact ions with low charge states, moderating polarization effects on ion mobility. Conversion of mobilities into cross-sections involves a reduction factor ξ for the actual mobility relative to that associated with elastic specular collisions with smooth surfaces. ξ is known to be 1.36 in air from Millikan's oil drop experiments. A similar enhancement effect ascribed to atomic-scale surface roughness has been found in numerical simulations. Adopting Millikan's value ξ=1.36 and assuming a spherical geometry yields a gas-phase protein density ρ(p)=0.949±0.053 g cm(-3) for all our protein data. This is substantially higher than the 0.67 g cm(-3) found in recent low-resolution DMA measurements of singly charged proteins. DMA-MS can distinguish nonspecific protein aggregates formed during the electrospray process from those formed preferentially in solution. The observed charge versus diameter relation is compatible with a protein charge reduction mechanism based on the evaporation of triethylammonium ions from electrosprayed drops.
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Maißer A, Premnath V, Ghosh A, Nguyen TA, Attoui M, Hogan CJ. Determination of gas phase protein ion densities via ion mobility analysis with charge reduction. Phys Chem Chem Phys 2011; 13:21630-41. [DOI: 10.1039/c1cp22127b] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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