Analytical Instrumentation Analytical Instrumentation: A Guide to Laboratory, Portable and Miniaturized Instruments G. McMahon © 2007 John Wiley & Sons, Ltd. ISBN: 978-0-470-02795-0 Analytical Instrumentation A Guide to Laboratory, Portable and Miniaturized Instruments First Edition GILLIAN MCMAHON School of Chemical Sciences Dublin City University Ireland Copyright © 2007 John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex PO19 8SQ, England Telephone (⫹44) 1243 779777 Email (for orders and customer service enquiries): For Sophie and Charlie Contents Page Foreword xi Preface xiii Acknowledgements xv Acronyms and Abbreviations xvii 1 Introduction 1 1.1 The Analytical Scientist 1 1.2 The Analytical Process 2 1.3 Analytical Instrumentation 3 1.4 Choosing the Right Instrument 4 Reference 6 SECTION I LABORATORY ANALYTICAL INSTRUMENTATION 7 2 Spectrometric Instruments 9 2.1 Molecular Spectrometry 9 2.1.1 Ultraviolet, Visible and Near Infrared 9 2.1.2 Infrared and Raman 15 2.1.3 Luminescence 25 2.1.4 Nuclear Magnetic Resonance 31 2.1.5 Mass Spectrometry 36 2.2 Atomic Spectrometry 49 2.2.1 A tomic Absorption Spectrometry and Atomic Fluorescence Spectrometry 50 2.2.2 Inductively Coupled Plasma–Optical Emission Spectrometry 53 2.2.3 Inductively Coupled Plasma–Mass Spectrometry 58 References 60 3 Separation Instruments 65 3.1 Gas Chromatography 65 3.2 High Performance Liquid Chromatography 74 3.3 Ion Chromatography 89 3.4 Capillary Electrophoresis 92 3.5 Supercritical Fluid Chromatography 100 viii Contents 3.6 Hyphenated (Hybrid) Instruments 103 3.6.1 Hyphenated Gas Chromatography Techniques 104 3.6.2 Hyphenated Liquid Chromatography Techniques 108 3.6.3 Hyphenated Capillary Electrophoresis Techniques 120 References 12 4 Imaging Instruments 125 4.1 Optical Microscopy 125 4.2 Confocal Microscopy 127 4.3 Electron Microscopy 129 4.3.1 Scanning Electron Microscopy 130 4.3.2 Transmission Electron Microscopy 133 4.4 Scanning Probe Microscopy 135 4.4.1 Scanning Tunnelling Microscopy 135 4.4.2 Atomic Force Microscopy 138 4.5 Spectral Imaging 141 References 145 5 Electrochemical Instruments 147 5.1 Potentiometry 147 5.2 Voltammetry 154 5.3 Conductimetry 159 References 161 6 Other Instruments 163 6.1 Thermogravimetric Analysis 163 6.2 Differential Scanning Calorimetry 166 6.3 X-ray Diffraction 170 References 172 SECTION II PORTABLE ANALYTICAL INSTRUMENTATION 173 The Drive for Portable Analytical Instruments 175 7 Portable Instruments in the Laboratory 177 7.1 Spectrometric Instruments 177 7.2 Separation Instruments 186 7.3 Imaging Instruments 189 7.4 Electrochemical Instruments 193 References 196 8 Portable Instruments in Various Applications 199 8.1 Medical Applications 199 8.1.1 Point-of-Care Technology 199 8.1.2 Blood Glucose Testing 200 8.1.3 Blood Coagulation Monitoring 206 8.1.4 Other Point-of-Care Devices 207 Contents ix 8.2 Environmental Applications 209 8.2.1 Field Devices 209 8.2.2 Water Quality Monitoring 209 8.2.3 Soil and Sediment Testing 211 8.2.4 Air Monitoring 211 8.3 Security and Defence Applications 212 8.4 Other Applications 214 References 215 SECTION III PROCESS ANALYTICAL INSTRUMENTATION 217 The Drive for Process Analysis 219 References 21 9 Process Analytical Instrumentation in Industry 223 9.1 In-Process Sampling 223 9.2 In-Process Analysis 226 9.2.1 Flow Injection Analysis 229 9.2.2 Spectroscopic Analysis 234 9.2.3 Separation Analysis 243 9.2.4 Imaging Analysis 245 9.2.5 Electrochemical Analysis 245 9.3 Laboratory Integrated Management Systems 246 References 247 SECTION IV MINIATURISED ANALYTICAL INSTRUMENTATION 251 The Drive for Miniaturised Analytical Instrumentation 253 References 254 10 Chip-based Instrumentation 255 10.1 The Development of Chip-based Analytical Devices 255 10.2 Challenges for Chip-based Analytical Devices 256 10.2.1 Moving and Mixing Fluids on a Chip 256 10.2.2 Fitting Components onto a Chip 259 10.2.3 Sampling and Detection Strategies 263 10.2.4 Understanding Processes on the Microscale 264 10.3 Chip-based Analytical Instruments 264 10.3.1 Lab-on-valve Flow Injection Analysis 264 10.3.2 Spectroscopic Devices 266 10.3.3 Separation Devices 268 10.3.4 Imaging Devices 272 10.3.5 Electrochemical Devices 273 10.3.6 Other Chip-based Devices 274 References 276 Index 283 Foreword This book has arisen from a series of lectures developed by Dr Gillan McMahon and de- livered to students on the taught postgraduate module on instrumentation at Dublin City University. Gillian was previously herself a student in DCU and since graduating, she has developed her analytical background initially in industry in the pharmachem arena, and more recently, as a very successful academic teacher and researcher. She gained a wealth of experience over a broad range of analytical techniques in the pharmachem industry, working with the Geotest Chemical Company (USA), Newport Pharmaceuti- cals (Ireland), Bristol-Myers Squibb (Ireland) and Zeneca Pharmaceuticals (UK). This experience applied not just to the use of techniques and methods, but also to data track- ing and compliance, which is a critical aspect for this sector. While with BMS, she was engaged in training of staff in advanced analytical techniques and compliance at other sites in Italy and Puerto Rico prior to production campaigns. Her academic career as an analytical scientist is equally impressive. She completed her PhD research at the Lombardi Cancer Centre, Georgetown University, USA and cur- rently is a lecturer at Dublin City University, where she teaches on the two national fl agship analytical courses (Analytical Science BSc and Instrumental Analysis MSc). In addition to her impressive research publications, and activities in professional bodies like the Royal Society of Chemistry and Institute of Chemistry of Ireland, Gillian has also won signifi cant external research funding, and has been the recipient of numerous individual awards for dissemination. Gillian therefore brings a rare, but vitally important mix of experience to this text. Ana- lytical science is a complex discipline, ranging from instrumentation, electronics, optics, through data processing and statistics, to the fundamental science of molecular recogni- tion and transduction. Analytical techniques are employed in an every-increasing range of applications. Along with synthetic chemistry, it provides the cornerstone of the pharm- ceutical industry. Without analytical information and new methods, the human genome project would never have been realised, and high throughput bioanalytical instruments are now helping to unravel the secrets of human genetic disposition to disease. Analytical instruments are routinely used to monitor the status of our environment and the quality of our food, and to enable individuals to track personal health indicators. And of course, where would forensic science be without analytical instruments? Devising a text to teach the principles and practice of analytical science to students with a wide diversity of educational backgrounds requires a balance between depth and breadth, and above all, a systematic, consistent approach. In this text, Gillian has met this formidable challenge, and the result is a clearly written and structured text that reveals the basis of the xii Foreword key instrumental methods, and the importance they play in many aspects of modern life. The clarity of the explanations will appeal to both undergraduate and postgraduate stu- dents, as well as scientists in industry and will help guide them in a practical way towards particular specialisms they may fi nd interesting as they move through their career. The text breaks new ground in that it takes the reader all the way from large, lab-based instruments through to on-line and in-line instruments for industry, to portable and hand- held equipment and fi nally to micro-scale lab-on-a-chip devices. This offers an alternative approach for teaching modern instrumentation. It covers a wide range of modern instru- mental methods in a practical and relevant way, including techniques not traditionally covered in analytical instrumentation texts, such as the imaging techniques which are be- coming ubiquitous in modern analytical laboratories. Gillian’s background in compliance comes through in the section covering on-line and in-line instruments wherein she covers not only the sensing and analytical techniques used in process analysis, but also the new FDA-driven phenomenon of process analytical technology (PAT). Always appealing to students is the ability to make the technology and science relevant. Gillian excels in this respect, linking analytical platforms to numerous specifi c examples of applications ranging across healthcare, the environment and the pharmaceutical industry. In conclusion, this is an exciting new resource for analytical science education that, I have no doubt, will prove to be popular with students and educators alike. I will certainly have a copy on my shelf! Dermot Diamond BSc, PhD (QUB), PGCE, MICI, MRSC, C.Chem. Science Foundation Ireland Principle Investigator in the ‘Adaptive Information Cluster’