Liquid Chromatography Mass Spectrometry Techniques and Applications
MODERN ANALYTICAL CHEMISTRY Series Editor: David Hercules University of Pittsburgh ANALYTICAL ATOMIC SPECTROSCOPY William G. Schrenk APPLIED ATOMIC SPECTROSCOPY Volumes 1 and 2 Edited by E. L. Grove CHEMICAL DERIVATIZATION IN ANALYTICAL CHEMISTRY Edited by R. W. Frei and J. F. Lawrence Volume 1: Chromatography Volume 2: Separation and Continuous Flow Techniques COMPUTER-ENHANCED ANALYTICAL SPECTROSCOPY Volume 1: Edited by Henk L. C. Meuzelaar and Thomas L. Isenhour Volume 2: Edited by Henk L. C. Meuzelaar ION CHROMATOGRAPHY Hamish Small ION-SELECTIVE ELECTRODES IN ANALYTICAL CHEMISTRY Volumes 1 and 2 Edited by Henry Freiser LIQUID CHROMATOGRAPHY /MASS SPECTROMETRY Techniques and Applications Alfred L. Yergey, Charles G. Edmonds, Ivor A. S. Lewis, and Marvin L. Vestal MODERN FLUORESCENCE SPECTROSCOPY Volumes 1-4 Edited by E. L. Wehry PHOTOELECTRON AND AUGER SPECTROSCOPY Thomas A. Carlson PRINCIPLES OF CHEMICAL SENSORS Jifl Janata TRANSFORM TECHNIQUES IN CHEMISTRY Edited by Peter R. Griffiths A Continuation Order Plan is available for this series. A continuation order will bring delivery of each new volume immediately upon publication. Volumes are billed only upon actual shipment. For further information please contact the publisher.
Liquid Chromatography Mass Techniques and Applications Alfred L. Yergey National Institutes of Health Bethesda, Maryland Charles G. Edmonds Battelle Pacific Northwest Laboratories Richland, Washington lvor A. S. Lewis King's College London, United Kingdom and Marvin L. Vestal Vestee Corporation Houston, Texas Spectrometry Springer Science+Business Media, LLC
Library of Congress Cataloging in Publication Data Liquid chromatography/mass spectrometry: techniques and applications / Alfred L. Yergey... [et al.]. p. cm. - (Modern analytical chemistry) Includes bibliographical references. ISBN 978-1-4899-3607-3 ISBN 978-1-4899-3605-9 (ebook) DOI 10.1007/978-1-4899-3605-9 1. Liquid chromatography. 2. Mass spectrometry. 1. Yergey, Alfred L. II. Series. QD79.C454L5537 1989 89-35915 543'.0894-dc20 CIP Springer Science+Business Media New York 1990 Originally published by Plenum Press New York in 1990. Softcover reprint of the hardcover I st edition 1990 AII rights reserved No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without written permis sion from the Publisher
Preface This book is intended both to be an introduction to techniques and applications of liquid chromatography/mass spectrometry and to serve as a reference for future workers. When we undertook its writing, we chose not to cover the field, particularly applications, exhaustively. Rather we wished to produce a book that would be of use to people just beginning to use the technique as well as to more advanced practitioners. In this regard, we have sought to highlight techniques and applications that are of current importance, while not neglecting descriptions of approaches that may be of significance in the future. We hope that we have succeeded in this. At the same time we hope that the bibliography, with indexes classified by author and title, will make this book of value to those who may disagree with our emphasis. ACKNOWLEDGMENTS. One of us (C.G.E.) wishes to acknowledge the encouragment of Professor J. A. McCloskey in undertaking this project. All four of us are grateful for the continuous and expert assistance of V. A. Edmonds in the preparation of the Bibliography. Alfred L. Y ergey Bethesda, Maryland Charles G. Edmonds Richland, Washington lvor A.S. Lewis London, England Marvin L. Vestal Houston, Texas v
Contents 1. Introduction.................................... 1 2. Direct Liquid Introduction Interfaces............. 5 2.1. Introduction.............................................. 5 2.2. Operating Principles....................................... 7 2.3. Specific DLI Interfaces..................................... 10 2.3.1. Capillary Inlets..................................... 10 2.3.2. Diaphragm Interfaces................................ 12 2.3.3. Nebulizing Interfaces................................. 14 2.4. Interfaces Using Unusual Fluids............................. 14 2.4.1. Continuous Flow FAB Interfaces....................... 14 2.4.2. SFC Interfaces...................................... 16 Additional References...................................... 17 3. Mechanical Transport Devices... 19 3.1. Introduction.............................................. 19 3.2. Continuous Transport Systems............................... 20 3.2.1. Moving-Wire Interfaces.............................. 20 3.2.2. Moving-Belt Interfaces............................... 20 3.2.3. The Heated-Wire Concentrator......................... 29 3. 3. Mechanized Fraction Collectors.............................. 30 3. 3. 1. Discussion......................................... 30 3.3.2. Future Prospects.................................... 30 4. Thermospray... 31 4. 1. Introduction.............................................. 31 4.2. Apparatus for Thermospray................................. 33 vii
viii Contents 4.2.1. The Vaporizer Probe... 34 4.2.2. The Thennospray Ion Source.......................... 34 4.2.3. Electron Gun....................................... 34 4.2.4. Discharge Electrode.................................. 35 4.2.5. Vacuum System..................................... 35 4.2.6. Thennospray Control System.......................... 36 4.2.7. Ion Optics and Mass Analyzer... 36 4.3. Mechanisms Involved in Thennospray Vaporization and Ionization 37 4.3.1. Vaporization and Nebulization in the Thennospray Capillary........................................... 37 4.3.2. Free Jet Expansion.................................. 60 4.4. Ionization Mechanisms..................................... 62 4.4.1. Production of Molecular Ions.......................... 62 4.4.2. Ion Evaporation from Charged Liquid Droplets........... 64 4.4.3. Ion Production from Charged Liquid Droplets- A Summary........................................ 70 4.4.4. Ion Production from Charged Solid Particles............. 72 4.4.5. Ionic Equilibria in a Vaporizing Droplet................. 73 4.4.6. Gas Phase Ion-Molecule Reactions..................... 75 4.4.7. Repeller Effects... 78 4.5. Optimizing Thennospray LC/MS for Particular Applications...... 79 4.5.1. Selection and Modification of LC Conditions............. 79 4.5.2. Selection of Ionization Technique...................... 80 4.5.3. Operating Temperatures.............................. 81 4.5.4. Vaporizer Tip Temperature............................ 83 4.6. Summary................................................ 83 Additional References...................................... 84 5. Particle Beam Interfaces... 87 6. LC/MS of Nucleic Acid Constituents... 89 6.1. Introduction.............................................. 89 6.2. LC/MS of Nucleobases and Related Compounds................ 91 6.2.1. Nucleobases........................................ 91 6.2.2. Methylxanthine Bases................................ 94 6.3. LC/MS of Nucleosides..................................... 99 6.3.1. Liquid Chromatography of Nucleosides.................. 99 6.3.2. Methods Employed for Nucleosides..................... 99 6.3.3. Performance Comparisons for Nucleosides... 100 6.3.4. Application of LC/MS to Nucleoside Analysis... 105 6.4. LC/MS of Nucleotides... 117
Contents ix 6.4.1. Methods Employed for Nucleotides and Dinucleotides... 117 6.4.2. Applications of LC/MS to Nucleotides and Dinucleotides... 117 6.5. Future Prospects... 123 Additional References...................................... 124 7. LC/MS of Conjugated Molecules... 127 7.1. Introduction... 127 7.2. Glucuronides... 128 7. 3. Acy lcarnitines............................................ 13 3 7.4. Sulfates... 134 Additional References...................................... 135 8. Applications of LC/MS to Amino Acids, Peptides, and Proteins... 137 8.1. Background... 137 8.2. Applications Using Immobilized Enzyme Digestions... 143 8.3. Limitations and Future Work... 145 9. A Bibliography of Combined Liquid Chromatography/Mass Spectrometry... 149 9.1. Introduction... 149 9.1.1. Methods... 149 9.1.2. Organization of the Bibliography... 150 Additional References... 151 9.2. Bibliography... 151 9. 3. Author Index... 255 9.4. Subject Index... 278 Index... 305