Meyer - Pitfalls and Errors of HPLC in Pictures

Further Titles for Chromatographers

S. Kromidas (ed.)

HPLC Made to Measure

A Practical Handbook for Optimization

2006

ISBN 3-527-31377-X

S. Kromidas

More Practical Problem Solving in HPLC

2005

ISBN 3-527-31113-0

V. R. Meyer

Practical High-Performance Liquid Chromatography

2010

ISBN 978-0-470-68218-0 or 978-0-470-68217-3

S. Kromidas

Practical Problem Solving in HPLC

2000

ISBN 3-527-29842-8

P. C. Sadek

Troubleshooting HPLC Systems

A Bench Manual

2000

ISBN 0-471-17834-9

U. D. Neue

HPLC Columns

Theory, Technology, and Practice

1997

ISBN 0-471-19037-3

L. R. Snyder, J. J. Kirkland, J. L. Glajch

Practical HPLC Method Development

1997

ISBN 0-471-00703-X

The Authors

Dr. Veronika R. Meyer

EMPA St. Gallen

Lerchenfeldstrasse 5

9014 St. Gallen

Switzerland

e-mail: veronika.meyer@empa.ch

All books published by Wiley-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate.

Library of Congress Card No.: applied for A catalogue record for this book is available from the British Library.

Bibliographic information published by the Deutsche Nationalbibliothek

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2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

All rights reserved (including those of translation into other languages). No part of this book may be reproduced in any form by photoprinting, microfilm, or any other means nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law.

Print ISBN: 978-3-527-33293-9

ePDF ISBN: 978-3-527-65913-5

ePub ISBN: 978-3-527-65912-8

mobi ISBN: 978-3-527-65911-1

oBook ISBN: 978-3-527-65910-4

1 wort = 1 millibild

(A picture says more than a thousand words)

Graffiti on the Baltzerstrasse in Bern

Preface

Errors are a common companion of all human activity, including work in the laboratory. Yet it is a great pity if erroneous results are produced with great effort and by using expensive instruments and demanding procedures. Therefore a book about sources of errors in high performance liquid chromatography, one of today's most widely used analytical methods, is not superfluous. Maybe the topic is not welcomed enthusiastically but I hope I have found a design which encourages reading and thinking.

In conception, at least, possible problems can be divided into two categories. Errors are troublesome opponents of accurate and precise analytical results which, however, can be understood; we need to remember and to anticipate them. In contrast, pitfalls are totally unexpected intruders and the secret behind them is difficult to discover. The worst are those which are not detected but which affect the result anyway. Nevertheless, the book does not distinguish between the two types. The readers decide how they classify them. With increasing experience in HPLC it should become easier to avoid the pitfalls.

The third edition could be expanded with new examples and proposals. Many people helped me with examples, hints or ideas on how to improve the text and figures. I want to thank all of them. Special thanks to the publisher who supports the idea of a picture book, not for children but for novices and experts in the analytical laboratory. I hope that the book will be a useful aid in daily laboratory work thanks to intelligible explanations and lucid illustrations.

Veronika R. Meyer

St. Gallen, August 2012

Introduction

This book is not an introductory text to HPLC and also not a troubleshooting guide of the kind what shall I do if my instrument does not work?. It does not replace such books but is intended to complement them. Some texts which, according to my personal opinion, are very useful and should therefore be present in the HPLC laboratory are listed on the next page.

Now this book on your desk is a picture book. The figures are at least as important as the texts; sometimes more information can be found in them than could be given in the short descriptions. It is possible, and in principle recommended, to study all the pages in sequence from beginning to end. This method guarantees that one learns about errors which are uncommon and unexpected. On the other hand each pair of pages is limited to one topic, linked to other pages by arrows only, and can therefore be studied in isolation. The index at the end of the book can help you find the right pages when a problem occurs, although it must be stated once again that quick troubleshooting advice is not usually provided.

The book is divided into three parts:

Part I briefly presents some basic facts about HPLC. Many topics may be absent because this is not a textbook, but the matter presented is of utmost relevance in HPLC. Thus the topics discussed should act as reminders and be used for revision. Whoever understands Part I knows a lot about HPLC more than it seems at first glance.

Part II lists the pitfalls and sources of error. They are in a logical sequence, as far as this is possible, following the flow path in an HPLC instrument, from the preparation of the mobile phase to data evaluation. The list is somewhat arbitrary, and not all errors are of equal importance with regard to their possible consequences. It would, however, be dangerous to distinguish between grave and harmless errors. A minute error can cause much damage under special circumstances.

Part III gives some hints on what can be done to avoid errors. Again this synopsis is very heterogeneous in character. This does not diminish its value, of course.

Incompleteness is an inevitable feature of this book. I am grateful for all hints on other pitfalls and sources of error or on how to avoid them.

Recommended Texts

Veronika R. Meyer

Practical High Performance Liquid Chromatography

Wiley, Chichester

5th edition 2010

John W. Dolan and Lloyd R. Snyder

Troubleshooting LC Systems

Humana Press, New Jersey

1989

Paul C. Sadek

Troubleshooting HPLC Systems: A Bench Manual

Wiley-Interscience, New York

2000

Stavros Kromidas

Practical Problem Solving in HPLC

Wiley-VCH, Weinheim

2000

Stavros Kromidas

More Practical Problem Solving in HPLC

Wiley-VCH, Weinheim

2004

Lloyd R. Snyder, Joseph J. Kirkland and Joseph L. Glajch

Practical HPLC Method Development

Wiley-Interscience, New York

2nd edition 1997

Norman Dyson

Chromatographic Integration Methods

Royal Society of Chemistry, London

2nd edition 1998

Part I

Fundamentals

In chromatography, a physical separation method, the components of a mixture are partitioned between two phases. One of the phases stays in its place and is called the stationary phase, whereas the other moves in a definite direction and is called the mobile phase.