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Prentice BM. Imaging with mass spectrometry: Which ionization technique is best? JOURNAL OF MASS SPECTROMETRY : JMS 2024; 59:e5016. [PMID: 38625003 DOI: 10.1002/jms.5016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/07/2024] [Accepted: 02/21/2024] [Indexed: 04/17/2024]
Abstract
The use of mass spectrometry (MS) to acquire molecular images of biological tissues and other substrates has developed into an indispensable analytical tool over the past 25 years. Imaging mass spectrometry technologies are widely used today to study the in situ spatial distributions for a variety of analytes. Early MS images were acquired using secondary ion mass spectrometry and matrix-assisted laser desorption/ionization. Researchers have also designed and developed other ionization techniques in recent years to probe surfaces and generate MS images, including desorption electrospray ionization (DESI), nanoDESI, laser ablation electrospray ionization, and infrared matrix-assisted laser desorption electrospray ionization. Investigators now have a plethora of ionization techniques to select from when performing imaging mass spectrometry experiments. This brief perspective will highlight the utility and relative figures of merit of these techniques within the context of their use in imaging mass spectrometry.
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Affiliation(s)
- Boone M Prentice
- Department of Chemistry, University of Florida, Gainesville, Florida, USA
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2
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Williams JD, Pu F, Sawicki JW, Elsen NL. Ultra-high-throughput mass spectrometry in drug discovery: fundamentals and recent advances. Expert Opin Drug Discov 2024; 19:291-301. [PMID: 38111363 DOI: 10.1080/17460441.2023.2293153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 12/06/2023] [Indexed: 12/20/2023]
Abstract
INTRODUCTION Ultra-high-throughput mass spectrometry, uHT-MS, is a technology that utilizes ionization and sample delivery technologies optimized to enable sampling from well plates at > 1 sample per second. These technologies do not need a chromatographic separation step and can be utilized in a wide variety of assays to detect a broad range of analytes including small molecules, lipids, and proteins. AREAS COVERED This manuscript provides a brief historical review of high-throughput mass spectrometry and the recently developed technologies that have enabled uHT-MS. The report also provides examples and references on how uHT-MS has been used in biochemical and chemical assays, nuisance compound profiling, protein analysis and high throughput experimentation for chemical synthesis. EXPERT OPINION The fast analysis time provided by uHT-MS is transforming how biochemical and chemical assays are performed in drug discovery. The potential to associate phenotypic responses produced by 1000's of compound treatments with changes in endogenous metabolite and lipid signals is becoming feasible. With the augmentation of simple, fast, high-throughput sample preparation, the scope of uHT-MS usage will increase. However, it likely will not supplant LC-MS for analyses that require low detection limits from complex matrices or characterization of complex biotherapeutics such as antibody-drug conjugates.
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Affiliation(s)
| | - Fan Pu
- Abbvie Discovery Research, North Chicago, IL, USA
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3
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Akbari B, Huber BR, Sherman JH. Unlocking the Hidden Depths: Multi-Modal Integration of Imaging Mass Spectrometry-Based and Molecular Imaging Techniques. Crit Rev Anal Chem 2023:1-30. [PMID: 37847593 DOI: 10.1080/10408347.2023.2266838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
Multimodal imaging (MMI) has emerged as a powerful tool in clinical research, combining different imaging modes to acquire comprehensive information and enabling scientists and surgeons to study tissue identification, localization, metabolic activity, and molecular discovery, thus aiding in disease progression analysis. While multimodal instruments are gaining popularity, challenges such as non-standardized characteristics, custom software, inadequate commercial support, and integration issues with other instruments need to be addressed. The field of multimodal imaging or multiplexed imaging allows for simultaneous signal reproduction from multiple imaging strategies. Intraoperatively, MMI can be integrated into frameless stereotactic surgery. Recent developments in medical imaging modalities such as magnetic resonance imaging (MRI), and Positron Emission Topography (PET) have brought new perspectives to multimodal imaging, enabling early cancer detection, molecular tracking, and real-time progression monitoring. Despite the evidence supporting the role of MMI in surgical decision-making, there is a need for comprehensive studies to validate and perform integration at the intersection of multiple imaging technologies. They were integrating mass spectrometry-based technologies (e.g., imaging mass spectrometry (IMS), imaging mass cytometry (IMC), and Ion mobility mass spectrometry ((IM-IM) with medical imaging modalities, offering promising avenues for molecular discovery and clinical applications. This review emphasizes the potential of multi-omics approaches in tissue mapping using MMI integrated into desorption electrospray ionization (DESI) and matrix-assisted laser desorption ionization (MALDI), allowing for sequential analyses of the same section. By addressing existing knowledge gaps, this review encourages future research endeavors toward multi-omics approaches, providing a roadmap for future research and enhancing the value of MMI in molecular pathology for diagnosis.
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Affiliation(s)
- Behnaz Akbari
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
| | - Bertrand Russell Huber
- Chobanian and Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
- Boston University Alzheimer's Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, USA
- US Department of Veteran Affairs, VA Boston Healthcare System, Boston, Massachusetts USA
- US Department of Veterans Affairs, National Center for PTSD, Boston, Massachusetts USA
| | - Janet Hope Sherman
- Chobanian and Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
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4
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Jiang LX, Hernly E, Hu H, Hilger RT, Neuweger H, Yang M, Laskin J. Nanospray Desorption Electrospray Ionization (Nano-DESI) Mass Spectrometry Imaging with High Ion Mobility Resolution. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:1798-1804. [PMID: 37463098 PMCID: PMC10513741 DOI: 10.1021/jasms.3c00199] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Untargeted separation of isomeric and isobaric species in mass spectrometry imaging (MSI) is challenging. The combination of ion mobility spectrometry (IMS) with MSI has emerged as an effective strategy for differentiating isomeric and isobaric species, which substantially enhances the molecular coverage and specificity of MSI experiments. In this study, we have implemented nanospray desorption electrospray ionization (nano-DESI) MSI on a trapped ion mobility spectrometry (TIMS) mass spectrometer. A new nano-DESI source was constructed, and a specially designed inlet extension was fabricated to accommodate the new source. The nano-DESI-TIMS-MSI platform was evaluated by imaging mouse brain tissue sections. We achieved high ion mobility resolution by utilizing three narrow mobility scan windows that covered the majority of the lipid molecules. Notably, the mobility resolution reaching up to 300 in this study is much higher than the resolution obtained in our previous study using drift tube IMS. High-resolution TIMS successfully separated lipid isomers and isobars, revealing their distinct localizations in tissue samples. Our results further demonstrate the power of high-mobility-resolution IMS for unraveling the complexity of biomolecular mixtures analyzed in MSI experiments.
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Affiliation(s)
- Li-Xue Jiang
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, United States
| | - Emerson Hernly
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, United States
| | - Hang Hu
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, United States
| | - Ryan T. Hilger
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, United States
| | | | - Manxi Yang
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, United States
| | - Julia Laskin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, United States
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5
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Borisjuk L, Horn P, Chapman K, Jakob PM, Gündel A, Rolletschek H. Seeing plants as never before. THE NEW PHYTOLOGIST 2023; 238:1775-1794. [PMID: 36895109 DOI: 10.1111/nph.18871] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/06/2023] [Indexed: 05/04/2023]
Abstract
Imaging has long supported our ability to understand the inner life of plants, their development, and response to a dynamic environment. While optical microscopy remains the core tool for imaging, a suite of novel technologies is now beginning to make a significant contribution to visualize plant metabolism. The purpose of this review was to provide the scientific community with an overview of current imaging methods, which rely variously on either nuclear magnetic resonance (NMR), mass spectrometry (MS) or infrared (IR) spectroscopy, and to present some examples of their application in order to illustrate their utility. In addition to providing a description of the basic principles underlying these technologies, the review discusses their various advantages and limitations, reveals the current state of the art, and suggests their potential application to experimental practice. Finally, a view is presented as to how the technologies will likely develop, how these developments may encourage the formulation of novel experimental strategies, and how the enormous potential of these technologies can contribute to progress in plant science.
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Affiliation(s)
- Ljudmilla Borisjuk
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466, Seeland-Gatersleben, Germany
| | - Patrick Horn
- Department of Biological Sciences, BioDiscovery Institute, University of North Texas, Denton, TX, 76203, USA
| | - Kent Chapman
- Department of Biological Sciences, BioDiscovery Institute, University of North Texas, Denton, TX, 76203, USA
| | - Peter M Jakob
- Institute of Experimental Physics 5, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Andre Gündel
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466, Seeland-Gatersleben, Germany
| | - Hardy Rolletschek
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466, Seeland-Gatersleben, Germany
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6
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Wang MF, Sohn AL, Samal J, Erning K, Segura T, Muddiman DC. Lipidomic Analysis of Mouse Brain to Evaluate the Efficacy and Preservation of Different Tissue Preparatory Techniques by IR-MALDESI-MSI. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:869-877. [PMID: 36988291 DOI: 10.1021/jasms.2c00353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Numerous preparatory methods have been developed to preserve the cellular and structural integrity of various biological tissues for different -omics studies. Herein, two preparatory methods for mass spectrometry imaging (MSI) were evaluated, fresh-frozen and sucrose-embedded, paraformaldehyde (PFA) fixed, in terms of ion abundance, putative lipid identifications, and preservation of analyte spatial distributions. Infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI)-MSI was utilized to compare the preparatory methods of interest with and without the use of the conventional ice matrix. There were 2.5-fold and 1.6-fold more lipid species putatively identified in positive- and negative-ion modes, respectively, for sucrose-embedded, PFA-fixed tissues without an ice matrix relative to the current IR-MALDESI-MSI gold-standard, fresh-frozen tissue preparation with an exogenous ice matrix. Furthermore, sucrose-embedded tissues demonstrated improved spatial distribution of ions resulting from the cryo-protective property of sucrose and paraformaldehyde fixation. Evidence from these investigations supports sucrose-embedding without ice matrix as an alternative preparatory technique for IR-MALDESI-MSI.
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Affiliation(s)
- Mary F Wang
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Alexandria L Sohn
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Juhi Samal
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Kevin Erning
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Tatiana Segura
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States
| | - David C Muddiman
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
- Molecular Education, Technology and Research Innovation Center, North Carolina State University, Raleigh, North Carolina 27695, United States
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7
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Liu L, Wang Z, Zhang Q, Mei Y, Li L, Liu H, Wang Z, Yang L. Ion Mobility Mass Spectrometry for the Separation and Characterization of Small Molecules. Anal Chem 2023; 95:134-151. [PMID: 36625109 DOI: 10.1021/acs.analchem.2c02866] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Longchan Liu
- The MOE Key Laboratory of Standardization of Chinese Medicines, The SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China
| | - Ziying Wang
- The MOE Key Laboratory of Standardization of Chinese Medicines, The SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China
| | - Qian Zhang
- The MOE Key Laboratory of Standardization of Chinese Medicines, The SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China
| | - Yuqi Mei
- The MOE Key Laboratory of Standardization of Chinese Medicines, The SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China
| | - Linnan Li
- The MOE Key Laboratory of Standardization of Chinese Medicines, The SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China
| | - Huwei Liu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing100871, China
| | - Zhengtao Wang
- The MOE Key Laboratory of Standardization of Chinese Medicines, The SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China
| | - Li Yang
- The MOE Key Laboratory of Standardization of Chinese Medicines, The SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China.,Shanghai Frontiers Science Center of TCM Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai201203, China
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8
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Arciniega C, Garrard KP, Guymon JP, Manni JG, Apffel A, Fjeldsted JC, Muddiman DC. Quasi-continuous infrared matrix-assisted laser desorption electrospray ionization source coupled to a quadrupole time-of-flight mass spectrometer for direct analysis from well plates. JOURNAL OF MASS SPECTROMETRY : JMS 2023; 58:e4902. [PMID: 36694312 PMCID: PMC9944147 DOI: 10.1002/jms.4902] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 12/03/2022] [Accepted: 01/07/2023] [Indexed: 06/17/2023]
Abstract
High-throughput screening (HTS) is a technique mostly used by pharmaceutical companies to rapidly screen multiple libraries of compounds to find drug hits with biological or pharmaceutical activity. Mass spectrometry (MS) has become a popular option for HTS given that it can simultaneously resolve hundreds to thousands of compounds without additional chemical derivatization. For this application, it is convenient to do direct analysis from well plates. Herein, we present the development of an infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) source coupled directly to an Agilent 6545 for direct analysis from well plates. The source is coupled to a quadrupole time-of-flight (Q-TOF) mass spectrometer to take advantage of the high acquisition rates without sacrificing resolving power as required with Orbitrap or Fourier-transform ion cyclotron resonance (FTICR) instruments. The laser used for this source operates at 100 Hz, firing 1 pulse-per-burst, and delivers around 0.7 mJ per pulse. Continuously firing this laser for an extended duration makes it a quasi-continuous ionization source. Additionally, a metal capillary was constructed to extend the inlet of the mass spectrometer, increase desolvation of electrospray charged droplets, improve ion transmission, and increase sensitivity. Its efficiency was compared with the conventional dielectric glass capillary by measured signal and demonstrated that the metal capillary increased ionization efficiency due to its more uniformly distributed temperature gradient. Finally, we present the functionality of the source by analyzing tune mix directly from well plates. This source is a proof of concept for HTS applications using IR-MALDESI coupled to a different MS platform.
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Affiliation(s)
- Cristina Arciniega
- FTMS Laboratory for Human Health Research, Department of ChemistryNorth Carolina State UniversityRaleighNC27695USA
| | - Kenneth P. Garrard
- FTMS Laboratory for Human Health Research, Department of ChemistryNorth Carolina State UniversityRaleighNC27695USA
- Precision Engineering ConsortiumNorth Carolina State UniversityRaleighNC27695USA
- Molecular Education, Technology and Research Innovation Center (METRIC)North Carolina State UniversityRaleighNC27695USA
| | - Jacob P. Guymon
- Precision Engineering ConsortiumNorth Carolina State UniversityRaleighNC27695USA
| | | | | | | | - David C. Muddiman
- FTMS Laboratory for Human Health Research, Department of ChemistryNorth Carolina State UniversityRaleighNC27695USA
- Molecular Education, Technology and Research Innovation Center (METRIC)North Carolina State UniversityRaleighNC27695USA
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9
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Caleb Bagley M, Garrard KP, Muddiman DC. The development and application of matrix assisted laser desorption electrospray ionization: The teenage years. MASS SPECTROMETRY REVIEWS 2023; 42:35-66. [PMID: 34028071 DOI: 10.1002/mas.21696] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 05/24/2023]
Abstract
In the past 15 years, ambient ionization techniques have witnessed a significant incursion into the field of mass spectrometry imaging, demonstrating their ability to provide complementary information to matrix-assisted laser desorption ionization. Matrix-assisted laser desorption electrospray ionization is one such technique that has evolved since its first demonstrations with ultraviolet lasers coupled to Fourier transform-ion cyclotron resonance mass spectrometers to extensive use with infrared lasers coupled to orbitrap-based mass spectrometers. Concurrently, there have been transformative developments of this imaging platform due to the high level of control the principal group has retained over the laser technology, data acquisition software (RastirX), instrument communication, and image processing software (MSiReader). This review will discuss the developments of MALDESI since its first laboratory demonstration in 2005 to the most recent advances in 2021.
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Affiliation(s)
- Michael Caleb Bagley
- FTMS Laboratory for Human Health Research, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA
| | - Kenneth P Garrard
- FTMS Laboratory for Human Health Research, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA
- The Precision Engineering Consortium, North Carolina State University, Raleigh, North Carolina, USA
- Molecular Education, Technology, and Research Innovation Center (METRIC), North Carolina State University, Raleigh, North Carolina, USA
| | - David C Muddiman
- FTMS Laboratory for Human Health Research, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA
- Molecular Education, Technology, and Research Innovation Center (METRIC), North Carolina State University, Raleigh, North Carolina, USA
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
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10
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High-end ion mobility mass spectrometry: A current review of analytical capacity in omics applications and structural investigations. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116761] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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11
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Gonzalez LE, Szalwinski LJ, Sams TC, Dziekonski ET, Cooks RG. Metabolomic and Lipidomic Profiling of Bacillus Using Two-Dimensional Tandem Mass Spectrometry. Anal Chem 2022; 94:16838-16846. [DOI: 10.1021/acs.analchem.2c03961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- L. Edwin Gonzalez
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Lucas J. Szalwinski
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Thomas C. Sams
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Eric T. Dziekonski
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - R. Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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12
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Bowman AP, Sawicki J, Talaty NN, Buck WR, Yang J, Wagner DS. Evaluation of Quantitative Platforms for Single Target Mass Spectrometry Imaging. Pharmaceuticals (Basel) 2022; 15:ph15101180. [PMID: 36297291 PMCID: PMC9609477 DOI: 10.3390/ph15101180] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 12/05/2022] Open
Abstract
(1) Imaging of pharmaceutical compounds in tissue is an increasingly important subsection of Mass Spectrometry Imaging (MSI). Identifying proper target engagement requires MS platforms with high sensitivity and spatial resolution. Three prominent categories of drugs are small molecule drugs, antibody-drug conjugate payloads, and protein degraders. (2) We tested six common MSI platforms for their limit of detection (LoD) on a representative compound for each category: a Matrix-Assisted Laser Desorption/Ionization (MALDI) Fourier Transform Ion Cyclotron, a MALDI-2 Time-of-Flight (ToF), a MALDI-2 Trapped Ion Mobility Spectrometry ToF, a Desorption Electrospray Ionization Orbitrap, and 2 Atmospheric Pressure-MALDI Triple Quadrupoles. Samples were homogenized tissue mimetic models of rat liver spiked with known concentrations of analytes. (3) We found that the AP-MALDI-QQQ platform outperformed all 4 competing platforms by a minimum of 2- to 52-fold increase in LoD for representative compounds from each category of pharmaceutical. (4) AP-MALDI-QQQ platforms are effective, cost-efficient mass spectrometers for the identification of targeted analytes of interest.
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Unsihuay D, Yin R, Sanchez DM, Yang M, Li Y, Sun X, Dey SK, Laskin J. High-resolution imaging and identification of biomolecules using Nano-DESI coupled to ion mobility spectrometry. Anal Chim Acta 2021; 1186:339085. [PMID: 34756271 DOI: 10.1016/j.aca.2021.339085] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 09/15/2021] [Accepted: 09/19/2021] [Indexed: 10/20/2022]
Abstract
Simultaneous spatial localization and structural characterization of molecules in complex biological samples currently represents an analytical challenge for mass spectrometry imaging (MSI) techniques. In this study, we describe a novel experimental platform, which substantially expands the capabilities and enhances the depth of chemical information obtained in high spatial resolution MSI experiments performed using nanospray desorption electrospray ionization (nano-DESI). Specifically, we designed and constructed a portable nano-DESI MSI platform and coupled it with a drift tube ion mobility (IM) spectrometer-mass spectrometer. We demonstrate imaging of drift time-separated ions with a high spatial resolution of better than ∼25 μm using uterine tissues on day 4 of pregnancy in mice. Collision cross-section measurements provide unique molecular descriptors of molecules observed in nano-DESI-IM-MSI necessary for their unambiguous identification by comparison with databases. Meanwhile, isomer-specific imaging reveals variations in the isomeric composition across the tissue. Furthermore, IM separation efficiently eliminates isobaric and isomeric interferences originating from solvent peaks, overlapping isotopic peaks of endogenous molecules extracted from the tissue, and products of in-source fragmentation, which is critical to obtaining accurate concentration gradients in the sample using MSI. The structural information provided by the IM separation substantially expands the molecular specificity of high-resolution MSI necessary for unraveling the complexity of biological systems.
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Affiliation(s)
- Daisy Unsihuay
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Ruichuan Yin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
| | | | - Manxi Yang
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Yingju Li
- Division of Reproductive Sciences, Cincinnati Children's Hospital Medical Centre and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA
| | - Xiaofei Sun
- Division of Reproductive Sciences, Cincinnati Children's Hospital Medical Centre and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA
| | - Sudhansu K Dey
- Division of Reproductive Sciences, Cincinnati Children's Hospital Medical Centre and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA
| | - Julia Laskin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA.
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14
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Matsushita S, Hasegawa T, Hiraoka M, Hayashi A, Suzuki Y. TLC-based MS Imaging Analysis of Glycosphingolipids and Glycerin Fatty Acid Esters after 1,2-Dichloroethane Washing. ANAL SCI 2021; 37:1491-1495. [PMID: 34690230 DOI: 10.2116/analsci.21c009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Matrix-assisted laser desorption/ionization-based mass spectrometry imaging (MSI) of separated lipids on thin-layer chromatography (TLC) plates or followed by blotted hydrophilic polyvinylidene fluoride (PVDF) membranes has become a powerful tool in lipidomic analyses. However, background peaks in MS spectra often cover lipid peaks in a low amount/ionization effect; consequently, only low intensities/resolutions MSI are obtained. To address the aforementioned problem, we attempted 1,2-dichloroethane pre-washing of TLC plates before development and found that backgrounds could successfully be removed from the TLC plate or PVDF membrane.
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Affiliation(s)
- Shoko Matsushita
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University
| | - Takuma Hasegawa
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University
| | - Marina Hiraoka
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University
| | - Aki Hayashi
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University
| | - Yusuke Suzuki
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University
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15
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Bagley MC, Pace CL, Ekelöf M, Muddiman DC. Infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) mass spectrometry imaging analysis of endogenous metabolites in cherry tomatoes. Analyst 2021; 145:5516-5523. [PMID: 32602477 DOI: 10.1039/d0an00818d] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report the spatially resolved metabolic profiling of cherry tomatoes using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI), a mass spectrometry imaging (MSI) technique that operates at ambient conditions and requires no sample derivatization. Tomatoes were flash frozen, cryosectioned and imaged with adequate spatial resolution to distinguish between the major tissue structures of a tomato including the skin, mesocarp, endocarp, locular tissue, septum, placenta, seed and seed coating. Metabolites were imaged from 100-1200 m/z, enabling significant coverage of a diverse array of metabolites including amino acids and lipids along with the major secondary metabolite classes: terpenes, phenolics, glycosides, and alkaloids. During the metabolic profiling, we found endogenous carotenoid hydrocarbons, namely lycopene or its structural isomer β-carotene, ionized as radical cations. To our knowledge, this is the first demonstration of ionizing hydrocarbons in the MSI field.
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Affiliation(s)
- M Caleb Bagley
- FTMS Laboratory for Human Health Research, Department of Chemistry, USA.
| | - Crystal L Pace
- FTMS Laboratory for Human Health Research, Department of Chemistry, USA.
| | - Måns Ekelöf
- FTMS Laboratory for Human Health Research, Department of Chemistry, USA.
| | - David C Muddiman
- FTMS Laboratory for Human Health Research, Department of Chemistry, USA. and Department of Plant and Microbial Biology, USA and Molecular Education, Technology, and Research Innovation Center (METRIC), North Carolina State University, Raleigh, NC 27695, USA
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16
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Pu F, Radosevich AJ, Sawicki JW, Chang-Yen D, Talaty NN, Gopalakrishnan SM, Williams JD, Elsen NL. High-Throughput Label-Free Biochemical Assays Using Infrared Matrix-Assisted Desorption Electrospray Ionization Mass Spectrometry. Anal Chem 2021; 93:6792-6800. [PMID: 33885291 DOI: 10.1021/acs.analchem.1c00737] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Mass spectrometry (MS) can provide high sensitivity and specificity for biochemical assays without the requirement of labels, eliminating the risk of assay interference. However, its use had been limited to lower-throughput assays due to the need for chromatography to overcome ion suppression from the sample matrix. Direct analysis without chromatography has the potential for high throughput if sensitivity is sufficient despite the presence of a matrix. Here, we report and demonstrate a novel direct analysis high-throughput MS system based on infrared matrix-assisted desorption electrospray ionization (IR-MALDESI) that has a potential acquisition rate of 33 spectra/s. We show the development of biochemical assays in standard buffers for wild-type isocitrate dehydrogenase 1 (IDH1), diacylglycerol kinase zeta (DGKζ), and p300 histone acetyltransferase (P300) to demonstrate the suitability of this system for a broad range of high-throughput lead discovery assays. A proof-of-concept pilot screen of ∼3k compounds is also shown for IDH1 and compared to a previously reported fluorescence-based assay. We were able to obtain reliable data at a speed amenable for high-throughput screening of large-scale compound libraries.
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Affiliation(s)
- Fan Pu
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Andrew J Radosevich
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - James W Sawicki
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - David Chang-Yen
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Nari N Talaty
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Sujatha M Gopalakrishnan
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Jon D Williams
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Nathaniel L Elsen
- Drug Discovery Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
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17
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Taylor M, Lukowski JK, Anderton CR. Spatially Resolved Mass Spectrometry at the Single Cell: Recent Innovations in Proteomics and Metabolomics. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:872-894. [PMID: 33656885 PMCID: PMC8033567 DOI: 10.1021/jasms.0c00439] [Citation(s) in RCA: 131] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/20/2021] [Accepted: 01/25/2021] [Indexed: 05/02/2023]
Abstract
Biological systems are composed of heterogeneous populations of cells that intercommunicate to form a functional living tissue. Biological function varies greatly across populations of cells, as each single cell has a unique transcriptome, proteome, and metabolome that translates to functional differences within single species and across kingdoms. Over the past decade, substantial advancements in our ability to characterize omic profiles on a single cell level have occurred, including in multiple spectroscopic and mass spectrometry (MS)-based techniques. Of these technologies, spatially resolved mass spectrometry approaches, including mass spectrometry imaging (MSI), have shown the most progress for single cell proteomics and metabolomics. For example, reporter-based methods using heavy metal tags have allowed for targeted MS investigation of the proteome at the subcellular level, and development of technologies such as laser ablation electrospray ionization mass spectrometry (LAESI-MS) now mean that dynamic metabolomics can be performed in situ. In this Perspective, we showcase advancements in single cell spatial metabolomics and proteomics over the past decade and highlight important aspects related to high-throughput screening, data analysis, and more which are vital to the success of achieving proteomic and metabolomic profiling at the single cell scale. Finally, using this broad literature summary, we provide a perspective on how the next decade may unfold in the area of single cell MS-based proteomics and metabolomics.
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Affiliation(s)
- Michael
J. Taylor
- Environmental Molecular Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Jessica K. Lukowski
- Environmental Molecular Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Christopher R. Anderton
- Environmental Molecular Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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18
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Optical Microscopy-Guided Laser Ablation Electrospray Ionization Ion Mobility Mass Spectrometry: Ambient Single Cell Metabolomics with Increased Confidence in Molecular Identification. Metabolites 2021; 11:metabo11040200. [PMID: 33801673 PMCID: PMC8065410 DOI: 10.3390/metabo11040200] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/23/2021] [Accepted: 03/25/2021] [Indexed: 12/13/2022] Open
Abstract
Single cell analysis is a field of increasing interest as new tools are continually being developed to understand intercellular differences within large cell populations. Laser-ablation electrospray ionization mass spectrometry (LAESI-MS) is an emerging technique for single cell metabolomics. Over the years, it has been validated that this ionization technique is advantageous for probing the molecular content of individual cells in situ. Here, we report the integration of a microscope into the optical train of the LAESI source to allow for visually informed ambient in situ single cell analysis. Additionally, we have coupled this ‘LAESI microscope’ to a drift-tube ion mobility mass spectrometer to enable separation of isobaric species and allow for the determination of ion collision cross sections in conjunction with accurate mass measurements. This combined information helps provide higher confidence for structural assignment of molecules ablated from single cells. Here, we show that this system enables the analysis of the metabolite content of Allium cepa epidermal cells with high confidence structural identification together with their spatial locations within a tissue.
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19
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Mesa Sanchez D, Creger S, Singla V, Kurulugama RT, Fjeldsted J, Laskin J. Ion Mobility-Mass Spectrometry Imaging Workflow. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:2437-2442. [PMID: 32841564 DOI: 10.1021/jasms.0c00142] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Mass spectrometry imaging (MSI) is a powerful technique for the label-free spatially resolved analysis of biological tissues. Coupling ion mobility (IM) separation with MSI allows for separation of isobars in the mobility dimension and increases confidence of peak assignments. Recently, imaging experiments have been implemented on several commercially available and custom-designed ion mobility instruments, making IM-MSI experiments more broadly accessible to the MS community. However, the absence of open access data analysis software for IM-MSI systems presents a bottleneck. Herein, we present an imaging workflow to visualize IM-MSI data produced on the Agilent 6560 ion mobility quadrupole time-of-flight system. Specifically, we have developed a Python script, the ion mobility-mass spectrometry image creation script (IM-MSIC), which interfaces Agilent's Mass Hunter Mass Profiler software with the MacCoss lab's Skyline software and generates drift time and mass-to-charge-selected ion images. In the workflow, Mass Profiler is used for an untargeted feature detection. The IM-MSIC script mediates user input of data, extracts ion chronograms utilizing Skyline's command-line interface, and then proceeds toward ion image generation within a single user interface. Ion image postprocessing is subsequently performed using different tools implemented in accompanying scripts. Though the current work only showcases Agilent IM-MSI data, this workflow can be readily adapted for use with most major instrument vendors.
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Affiliation(s)
- Daniela Mesa Sanchez
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, United States
| | - Steve Creger
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, United States
| | - Veerupaksh Singla
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra 400076, India
| | | | - John Fjeldsted
- Agilent Technologies Inc., Santa Clara, California 95051, United States
| | - Julia Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, United States
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20
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Rivera ES, Djambazova KV, Neumann EK, Caprioli RM, Spraggins JM. Integrating ion mobility and imaging mass spectrometry for comprehensive analysis of biological tissues: A brief review and perspective. JOURNAL OF MASS SPECTROMETRY : JMS 2020; 55:e4614. [PMID: 32955134 PMCID: PMC8211109 DOI: 10.1002/jms.4614] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/27/2020] [Accepted: 07/02/2020] [Indexed: 05/02/2023]
Abstract
Imaging mass spectrometry (IMS) technologies are capable of mapping a wide array of biomolecules in diverse cellular and tissue environments. IMS has emerged as an essential tool for providing spatially targeted molecular information due to its high sensitivity, wide molecular coverage, and chemical specificity. One of the major challenges for mapping the complex cellular milieu is the presence of many isomers and isobars in these samples. This challenge is traditionally addressed using orthogonal liquid chromatography (LC)-based analysis, though, common approaches such as chromatography and electrophoresis are not able to be performed at timescales that are compatible with most imaging applications. Ion mobility offers rapid, gas-phase separations that are readily integrated with IMS workflows in order to provide additional data dimensionality that can improve signal-to-noise, dynamic range, and specificity. Here, we highlight recent examples of ion mobility coupled to IMS and highlight their importance to the field.
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Key Words
- IMS
- desorption electrospray ionization, DESI
- drift tube ion mobility spectrometry, DTIMS
- high-field asymmetric waveform ion mobility, FAIMS
- imaging mass spectrometry
- infrared matrix-assisted laser desorption electrospray ionization, IR-MALDESI
- ion mobility
- laser ablation electrospray ionization, LAESI
- lipids
- liquid extraction surface analysis, LESA
- liquid microjunction, (LMJ)
- matrix-assisted laser desorption electrospray ionization, MALDI
- metabolites
- proteins
- tissue analysis
- trapped ion mobility spectrometry, TIMS
- travelling wave ion mobility spectrometry, TWIMS
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Affiliation(s)
- Emilio S. Rivera
- Department of Biochemistry, Vanderbilt University, 607 Light Hall, Nashville, TN 37205, USA
- Mass Spectrometry Research Center, Vanderbilt University, 465 21 Ave S #9160, Nashville, TN 37235, USA
| | - Katerina V. Djambazova
- Mass Spectrometry Research Center, Vanderbilt University, 465 21 Ave S #9160, Nashville, TN 37235, USA
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, Station B 351822, Nashville, TN 37235, USA
| | - Elizabeth K. Neumann
- Department of Biochemistry, Vanderbilt University, 607 Light Hall, Nashville, TN 37205, USA
- Mass Spectrometry Research Center, Vanderbilt University, 465 21 Ave S #9160, Nashville, TN 37235, USA
| | - Richard M. Caprioli
- Department of Biochemistry, Vanderbilt University, 607 Light Hall, Nashville, TN 37205, USA
- Mass Spectrometry Research Center, Vanderbilt University, 465 21 Ave S #9160, Nashville, TN 37235, USA
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, Station B 351822, Nashville, TN 37235, USA
- Department of Pharmacology, Vanderbilt University, 2220 Pierce Avenue, Nashville, TN 37232, USA
- Department of Medicine, Vanderbilt University, 465 21 Ave S #9160, Nashville, TN 37235, USA
| | - Jeffrey M. Spraggins
- Department of Biochemistry, Vanderbilt University, 607 Light Hall, Nashville, TN 37205, USA
- Mass Spectrometry Research Center, Vanderbilt University, 465 21 Ave S #9160, Nashville, TN 37235, USA
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, Station B 351822, Nashville, TN 37235, USA
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21
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Pu F, Elsen NL, Williams JD. Emerging Chromatography-Free High-Throughput Mass Spectrometry Technologies for Generating Hits and Leads. ACS Med Chem Lett 2020; 11:2108-2113. [PMID: 33214819 PMCID: PMC7667647 DOI: 10.1021/acsmedchemlett.0c00314] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 09/21/2020] [Indexed: 12/11/2022] Open
Abstract
Mass spectrometry (MS) detection can offer unmatched selectivity and sensitivity. The use of MS without chromatography greatly increases the throughput, making it suitable for high throughput screening. However, the trade-offs of direct MS detection need to be carefully evaluated along with the development of novel strategies to ensure successful implementation. In this review, we will discuss the pros and cons of chromatography-free MS and discuss some of the currently used and future technologies being investigated to enable high-throughput MS.
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Affiliation(s)
- Fan Pu
- Drug Discovery Science and Technology, AbbVie Inc., 1 North Waukegan Road, North
Chicago, Illinois 60064, United States
| | - Nathaniel L. Elsen
- Drug Discovery Science and Technology, AbbVie Inc., 1 North Waukegan Road, North
Chicago, Illinois 60064, United States
| | - Jon D. Williams
- Drug Discovery Science and Technology, AbbVie Inc., 1 North Waukegan Road, North
Chicago, Illinois 60064, United States
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22
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Pace CL, Muddiman DC. Direct Analysis of Native N-Linked Glycans by IR-MALDESI. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:10.1021/jasms.0c00176. [PMID: 32603137 PMCID: PMC8285077 DOI: 10.1021/jasms.0c00176] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Glycan analysis by mass spectrometry has rapidly progressed due to the interest in understanding the role of glycans in disease and tumor progression. Glycans are complex molecules that pose analytical challenges due to their isomeric compositions, labile character, and ionization preferences. This study sought to demonstrate infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) as a novel approach for the direct analysis of N-linked glycans. The glycoprotein bovine fetuin was chosen for this analysis as its glycome is well-characterized and heavily composed of sialylated glycans. Native N-linked glycans produced by enzymatic cleavage (via PNGase F) of bovine fetuin were analyzed directly by IR-MALDESI in both positive and negative ionization mode. In this study, we detected 12 N-linked glycans in negative mode and 4 N-linked glycans in positive mode, a significant increase in the amount of underivatized glycans detected by other ionization sources. Importantly, all N-linked glycans detected contained at least one sialic acid residue, which are known to be labile. This work represents a critical first step for N-linked glycan analysis by IR-MALDESI with future efforts directed at mass spectrometry imaging.
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Affiliation(s)
- Crystal L. Pace
- FTMS Laboratory for Human Health Research, Department of Chemistry, North Carolina State University, Raleigh, NC, USA 27695
| | - David C. Muddiman
- FTMS Laboratory for Human Health Research, Department of Chemistry, North Carolina State University, Raleigh, NC, USA 27695
- Molecular Education, Technology and Research Innovation Center (METRIC), North Carolina State University, Raleigh, NC, USA 27695
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