Direct Analysis in Real Time Mass Spectrometry: Principles and Practices of DART-MS

Clear, comprehensive, and state of the art, the groundbreaking book on the emerging technology of direct analysis in real time mass spectrometry Written by a noted expert in the field, Direct Analysis in Real Time Mass Spectrometry offers a review of the background and the most recent developments in DART-MS. Invented in 2005, DART-MS offers a wide range of applications for solving numerous analytical problems in various environments, including food science, forensics, and clinical analysis. The text presents an introduction to the history of the technology and includes information on the theoretical background, for exampleon the ionization mechanism. Chapters on sampling and coupling to different types of mass spectrometers are followed by a comprehensive discussion of a broad range of applications. Unlike most other ionization methods, DART does not require laborious sample preparation, as ionization takes place directly on the sample surface. This makes the technique especially attractive for applications in forensics and food science. Comprehensive in scope, this vital text: -Sets the standard on an important and emerging ionization technique -Thoroughly discusses all the relevant aspects from instrumentation to applications -Helps in solving numerous analytical problems in various applications, for example food science, forensics, environmental and clinical analysis -Covers mechanisms, coupling to mass spectrometers, and includes information on challenges and disadvantages of the technique Academics, analytical chemists, pharmaceutical chemists, clinical chemists, forensic scientists, and others will find this illuminating text a must-have resource for understanding the most recent developments in the field.

Table of Contents:
Preface xv About the Editor xvii 1 Introduction of Mass Spectrometry and Ambient Ionization Techniques 1 Yiyang Dong, Jiahui Liu, and Tianyang Guo 1.1 Evolution of Analytical Chemistry and Its Challenges in the Twenty-First Century 1 1.2 Historical Overview of Mass Spectrometry and Its Role in Contemporary Analytical Chemistry 5 1.3 Desorption/Ionization in Mass Spectrometry 12 1.3.1 Electronic Ionization (EI) 13 1.3.2 Chemical Ionization (CI) 14 1.3.3 Fast Atom/Ion Bombardment Ionization (FAB) 15 1.3.4 Electrospray Ionization (ESI) 16 1.3.5 Matrix Assisted Laser Desorption/Ionization (MALDI) 18 1.3.6 Field Desorption (FD) or Field Ionization (FI) 19 1.3.7 Plasma Desorption (PD) (ICP, LTP, DART) 19 1.4 Ambient Ionization and Direct Analysis in Real Time 21 1.4.1 Ambient Ionization 21 1.4.2 Direct Analysis in Real Time 24 1.4.2.1 Mechanisms 24 1.4.2.2 Parameters 27 1.4.2.3 Devices 29 References 30 2 DART Mass Spectrometry: Principle and Ionization Facilities 43 David Rondeau 2.1 Introduction 43 2.2 Metastable Gas Stream Formation 43 2.3 Ionization Mechanisms in Positive DART 45 2.3.1 Generation of Primary Ions by Ambient Air Ionization 46 2.3.2 Formation of the Protonated Molecules 50 2.3.3 Formation of the Ammonium Adducts 54 2.3.4 Formation of the Radical Cations and Their Fragments 55 2.3.5 Matrix Effects in DART Due to Sample Solvents 59 2.4 Ionization Mechanisms in Negative DART 65 2.4.1 Generation of Primary Ions by Ambient Air Ionization 65 2.4.2 Formation of Deprotonated Molecules 68 2.4.3 Formation of Radical Anions 69 2.4.4 Formation of Anionic Adducts 70 2.5 Some Parameters Affecting the DART Mass Spectra 71 2.5.1 Substitution of Helium by Nitrogen or Argon 71 2.5.2 The Temperature of the Gas Stream 75 2.5.3 The Internal Energy of Ions in DART-MS 76 2.6 Conclusion 78 References 78 3 Sampling and Analyte Enrichment Strategies for DART-MS 81 WenMa, Xianjiang Li, and Huwei Liu 3.1 Dilution Strategy for Sticky Sample Analysis 81 3.2 Purification Strategy for Eliminating the Matrix Interference 82 3.2.1 Liquid Phase Extraction 82 3.2.2 Solid Phase Extraction (SPE) 86 3.2.3 Solid Phase Microextraction (SPME) 87 3.3 Derivatization Strategy to Decrease Polarity and Enhance Volatility 89 3.4 Conclusions 91 References 91 4 Optimization of DART andMass Spectrometric Parameters 97 GuohuaWu andWushuang Li 4.1 Introduction 97 4.2 Effect ofWorking Gas Type, Gas Flow Rate, and Its Temperature 98 4.2.1 Gas Type 98 4.2.2 Gas Flow Rate 99 4.2.3 TheWorking Gas Temperature of DART Ionization Source 100 4.3 Effects of Grid Electrode Voltage and Sampling Speed 102 4.3.1 Effect of Grid Electrode Voltage 102 4.3.2 Effect of Sampling Speed 103 4.4 Effect of the SamplingMode 104 4.4.1 SamplingMethods 104 4.4.2 Position and Angle of the DART Ion Source 105 4.5 Effect of Ion Mode 106 4.6 Effect of Solvent Type and Reagents 108 4.7 Summary 109 References 109 5 Interfacing DART to Extend Analytical Capabilities 115 Yiding Zhang, Shuting Xu, and Yu Bai 5.1 Introduction 115 5.2 Interfacing DART with Different Separation Techniques 116 5.2.1 Solid Samples 116 5.2.2 Gaseous Samples 118 5.2.3 Liquid Samples 119 5.2.3.1 Liquid Chromatography 119 5.2.3.2 Capillary Electrophoresis 123 5.3 Techniques of Interfacing DART with Other Analytical Techniques 125 5.3.1 Surface Plasmon Resonance 125 5.3.2 Ion Mobility Spectrometry 126 5.4 Conclusion and Perspectives 129 References 129 6 Application of DART-MS in Foods and Agro-Products Analysis 133 Canping Pan and Lei Wang 6.1 Introduction 133 6.2 Applications of DART-MS in Agriculture and Food Science 134 6.2.1 DART-MS in Pesticide Residue Analysis 134 6.2.1.1 Fast Screening Purposes 134 6.2.1.2 Screening Highly Hazardous Pesticides in Agrochemical Formulations 140 6.2.1.3 QuantitativeMRM Residue Method 147 6.2.2 Veterinary Drug Residue Detection 148 6.2.3 Fast Detection of Melamine in Milk 149 6.2.4 Detection of Mycotoxins in Cereals 150 6.2.5 Food Component Rapid Analysis 151 6.2.6 Contaminations in Food Contact Materials (FCMs) 156 6.3 Conclusion 156 References 157 7 Application of DART-MS for Industrial Chemical Analysis 163 Qiang Ma 7.1 Application on Household Items 163 7.1.1 Polydimethylsiloxane (PDMS) Analysis in Articles for Daily Use 163 7.1.2 Identification of Sulfides in Drywall 165 7.1.3 Phosphoric Acid Esters Screening in Aqueous Samples 168 7.2 Application on Food Packaging Safety and Quality Control 172 7.2.1 Identification of PDMS in Food Packaging Materials 172 7.2.2 Identification of Polymer Additives in Food and Food Packaging 175 7.2.3 Identification of Residue Primary Aromatic Amines (PAAs) in Food Packaging Materials 176 7.3 Application on Pharmaceutical Products 177 7.3.1 Toxic Glycols Identification 177 7.3.2 Identification of Active Ingredients in Chinese Herbal Medicines 179 7.4 Application on Cosmetics Quality Control 182 7.4.1 Screening of Glucocorticoids Illegal Addition 182 7.5 Application on Other Industrial Chemical Fields 184 7.5.1 Ink Discrimination on Questioned Document 184 7.5.2 Ionic Liquids Identification 189 7.6 Conclusions 190 References 190 8 Application of Direct Analysis in Real Time Coupled toMass Spectrometry (DART-MS) for the Analysis of Environmental Contaminants 193 Maxime C. Bridoux and Sébastien Schramm 8.1 Introduction 193 8.2 Screening and Quantitative Analysis of Pesticides 194 8.3 Flame Retardants DART-MS Analysis 204 8.3.1 Organophosphorus Flame Retardants (OPFRs) 204 8.3.2 Brominated Flame Retardants (BFRs) 207 8.4 Use of DART-MS for the Analysis of Personal Care Products (PCPs) 210 8.4.1 Screening of Organic UV Filters inWater 210 8.4.2 Screening of Phthalic Acid Diesters 211 8.4.3 HPLC-DART-MS Analysis of Parabens 211 8.5 Use of DART-MS for the Analysis of Aerosols 212 8.5.1 Online DART for Aerosols Analysis 212 8.5.2 Offline DART Methods 213 8.5.3 Advantages and Limitations of DART-MS for Aerosols Characterization 213 8.6 Miscellaneous Environmental Application of DART-MS 214 8.7 Conclusions 215 References 216 9 Application of DART-MS in Clinical and Pharmacological Analysis 223 Yue Li 9.1 Introduction 223 9.2 Sample Preparation 224 9.3 Applications of DART-MS 225 9.3.1 Rapid Determination of Small Organic Compounds in Biological Samples 225 9.3.1.1 Analysis of a Bitter Herbal Medicine Gentiana scabra Root Extract 225 9.3.1.2 Simultaneous Determination of 3-Chlorotyrosine and 3-Nitrotyrosine in Human Plasma 226 9.3.1.3 Rapid Screening for Methamphetamine, 3,4-Methylene-dioxymethamphetamine, andTheir Metabolites in Urine 227 9.3.2 Newborn Screening for Phenylketonuria 227 9.3.3 DART-MS Analysis of Skin Metabolome Changes in Ultraviolet B-Induced Mice 228 9.3.4 Application in Detection of Breast Cancer 231 9.3.5 Transmission Mode DART-MS for Fast Untargeted Metabolic Fingerprinting 232 9.3.6 Applications of Confined DART Ion Source for Online In vivo Analysis of Human Breath 233 9.3.6.1 Real-Time Analysis of Exhaled Breath 234 9.3.6.2 Real-Time Monitoring of Oral Anesthetic Drug 235 9.4 Challenges and Limitations 236 9.5 Recent Advancements 237 References 238 10 DART-MS Applications in Pharmaceuticals 241 Karina G. Putri, Qianwen Wu, and Young P. Jang 10.1 Pharmaceutical Analysis 241 10.2 Quality Assurance 243 10.3 Illegal Active Pharmaceutical Ingredients and Counterfeit Drugs 244 10.4 Drug Development 247 References 251 11 Application of DART-MS in Natural Phytochemical Research 255 Vikas Bajpai, Awantika Singh, Brijesh Kumar, and Kunnath P. Madhusudanan 11.1 Introduction 255 11.2 Direct Analysis in Real Time (DART)Mass Spectrometry 256 11.3 DART-MS Parameter Optimization for Phytochemical Analysis 256 11.4 Applications of DART-MS in Phytochemical Research 257 11.4.1 Qualitative Phytochemical Analysis 257 11.4.2 Cell Culture Analysis 261 11.4.3 Analysis of Volatiles 261 11.4.4 Species Identification 262 11.4.5 Metabolic Profiling and Multivariate Analysis 263 11.4.6 Quantitative Analysis 274 11.5 Hyphenated DART-MS Techniques for Phytochemical Analysis 276 11.5.1 GC and HPLC-DART-MS 276 11.5.2 TLC/HPTLC-DART-MS 276 11.5.3 Capillary Electrophoresis-DART MS 277 11.5.4 DART-IMS-MS 277 11.5.5 Other Coupling Techniques 277 11.6 Improving Sensitivity of DART-MS for Phytochemical Analysis 278 11.6.1 Solvents and Gases 278 11.6.2 Matrix Suppression 279 11.7 DART -MS as Process Analytical Technology 279 11.8 Future Perspective 280 References 280 12 Miscellaneous Applications of DART-MS 291 Yoshihito Okada 12.1 Introduction 291 12.2 Usefulness of Negative-IonMode 292 12.3 Application to Archeology and Conservation 293 12.4 Application by Using TLC 293 12.5 Application to Low Volatility, ChemicalWarfare, and Homeland Security 294 12.6 Pheromone Profiles from Live Animals in Parallel with Behavior 295 12.7 Application to Distinction of Plants with Similarity 296 12.8 Application to Space 298 12.9 Application to Bituminous Coals 298 12.10 Application to Detection of Nicotine 298 12.11 Other Potential Applications of DART-MS 299 12.11.1 Instantaneous Screening for Counterfeit Drugs with No Sample Preparation [26-1] 299 12.11.2 Direct Analysis of Drugs in Pills and Capsules with No Sample Preparation [26-2] 300 12.11.3 Detection of Lycopene in Tomato Skin [26-3] 300 12.11.4 Distribution of Capsaicin in Chili Peppers [26-4] 302 12.11.5 Detection of Unstable Compound Released by Chopped Chives [26-5] 302 12.11.6 Rapid Detection of Fungicide in Orange Peel [26-6] 304 12.11.7 "Laundry Detective": Identification of a Stain [26-7] 304 12.11.8 Detection of the Peroxide Explosives TATP and HMTD [26-8] 306 12.11.9 Instantaneous Detection of Explosives on Clothing [26-9] 306 12.11.10 Rapid Detection and Exact Mass Measurements of Trace Components in a Herbicide [26-10] 308 12.11.11 Rapid Analysis of p-Phenylenediamine Antioxidants in Rubber [26-11] 308 Acknowledgment 309 References 309 13 Inherent Limitations and Prospects of DART-MS 313 Tim T. Häbe, Matthias Nitsch, and Gertrud E. Morlock 13.1 Aspects of Inherent Limitations of DART-MS 313 13.1.1 Gas Settings 314 13.1.1.1 Type of Gas 314 13.1.1.2 Gas Temperature 314 13.1.1.3 Gas Flow Rate 317 13.1.2 Voltage of Electrodes 317 13.1.3 Sample Introduction and Positioning 318 13.1.4 Detection System and Mass Range 318 13.1.5 Matrix Effects and the Need for Chromatography 319 13.1.6 Buffer and Salt Effects 321 13.1.7 Sample Carrier and Solvent 322 13.1.8 Humidity Effects 322 13.1.9 Use of Isotopically Labeled Standards 322 13.1.10 Dopant and Derivatization 323 13.2 DART versus Other Ambient Ion Sources 324 13.3 Prospects of DART-MS 326 13.3.1 Automation and Miniaturized DART-MS 326 13.3.2 Sample Preparation, Preconcentration, and Introduction 327 13.3.3 Ion Focusing and Flexible Ion Transportation 327 13.3.4 Quantitative Surface Scanning and Imaging by DART-MS 328 13.3.5 Hyphenation of Effect-Directed Analysis and DART-MS 331 13.3.6 Thermal Separations by Temperature Gradients 331 13.3.7 Aerosol, in situ and in stillo Chemical Reaction and Kinetic Monitoring 332 13.3.8 High Resolution and Data Analysis 332 13.4 Concluding Remarks 333 References 333 Index 345

About the Author :
Yiyang Dong is full professor and director of Food Safety & Risk Assessment Laboratory of Beijing University of Chemical Technology (BUCT) in Beijing, China. He is frequently invited as reviewer for journals such as Biosensors and Bioelectronics, Analyst, Analytical Methods, and Journal of Molecular Recognition.