Proton Transfer Reaction Mass Spectrometry -- Contents -- Preface -- SECTION 1 PRINCIPLES -- 1 Background -- 1.1 Volatile Organic Compounds in the Earth's Atmosphere -- 1.2 Volatile Organic Compounds in Other Environments -- 1.3 Techniques for VOC Measurements -- 1.3.1 Gas Chromatography -- 1.3.2 Ion Mobility Spectrometry -- 1.3.3 The Flowing Afterglow Technique -- 1.3.4 The Selected Ion Flow Tube -- 1.4 Emergence of Proton Transfer Reaction Mass Spectrometry -- 1.4.1 Historical Background -- 1.4.2 Compound Identification Using PTR-MS -- 1.4.3 An Introduction to Quantitative Aspects of PTR-MS -- 1.4.4 A Comparison between PTR-MS and SIFT-MS -- References -- 2 Chemical Ionization: Chemistry, Thermodynamics and Kinetics -- 2.1 Introduction -- 2.2 Proton Transfer -- 2.2.1 Energy Units -- 2.2.2 Thermodynamics of Proton Transfer -- 2.2.3 Kinetics of Proton Transfer -- 2.2.3.1 Background -- 2.2.3.2 Theoretical Prediction of Proton Transfer Rate Coefficients -- 2.2.3.3 Illustrative Calculations of Proton Transfer Rate Coefficients and Comparison with Experiment -- 2.2.4 Reagents and Mechanisms -- 2.2.4.1 Chemistry of H3O+ Reactions -- 2.2.4.2 Reactions of Hydrated Hydronium Clusters -- 2.2.4.3 Alternative Proton Donors -- 2.3 Other Chemical Ionization Processes -- References -- 3 Experimental: Components and Principles -- 3.1 Introduction -- 3.2 Ion Extraction and Ion Optics -- 3.2.1 Ion Acceleration -- 3.2.2 Ion Steering -- 3.2.3 Ion Lenses -- 3.2.4 Simulation of Ion Trajectories -- 3.3 Ion Sources -- 3.3.1 Hollow Cathode Discharge Ion Source -- 3.3.2 IonĐMolecule Chemistry Leading to H3O+ Production -- 3.3.3 Alternative Ion Sources -- 3.3.4 Generating Reagent Ions Other Than H3O+ -- 3.4 Drift Tubes -- 3.4.1 Practical Aspects -- 3.4.2 Ion Mobility and Transit Times -- 3.4.3 IonĐMolecule Collision Energies -- 3.4.4 Ion Cluster Distributions.

3.5 Mass Spectrometry -- 3.5.1 Some Important Definitions -- 3.5.1.1 Ion Mass and Mass-to-Charge Ratio -- 3.5.1.2 Mass Resolution -- 3.5.1.3 Transmission and Dynamic Range -- 3.5.2 Quadrupole Mass Spectrometry -- 3.5.2.1 Basic Principles of the Quadrupole Mass Spectrometer -- 3.5.2.2 Practical Issues -- 3.5.3 Quadrupole Ion Trap Mass Spectrometry -- 3.5.3.1 Basic Principles -- 3.5.3.2 Collision-Induced Dissociation -- 3.5.3.3 Three-Dimensional Quadrupole Ion Traps in PTR-MS -- 3.5.3.4 The Linear Ion Trap in PTR-MS -- 3.5.4 Time-of-flight Mass Spectrometry -- 3.5.4.1 Basic Principles of TOF-MS -- 3.5.4.2 Improving the Resolution: Spatial Focusing -- 3.5.4.3 Reflectron TOF-MS -- 3.5.4.4 Mass Calibration in TOF-MS -- 3.5.4.5 Advantages and Limitations of TOF-MS -- 3.5.4.6 TOF-MS Analysers in PTR-MS -- 3.6 Ion Detectors -- 3.6.1 Discrete Dynode Detector -- 3.6.2 Channel Electron Multiplier -- 3.6.3 Microchannel Plate Detector -- 3.7 Analogue versus Digital Signal Processing -- References -- 4 Quantitative Analysis -- 4.1 Introduction -- 4.2 Extracting the Concentration of a Trace Gas from PTR-MS -- 4.3 Normalized Counts per Second -- 4.4 Why Calibrate? -- 4.5 Calibration Techniques -- 4.5.1 Static Gas Calibration -- 4.5.2 Dynamic Methods -- 4.5.3 Alternative Dynamic Calibration Procedures -- 4.6 Effect of Humidity -- 4.7 Accuracy, Precision and Limit of Detection -- 4.8 Validation of PTR-MS -- References -- SECTION 2 APPLICATIONS -- 5 PTR-MS in the Environmental Sciences -- 5.1 Background -- 5.2 Use of Reagent Ions Other Than H3O+ -- 5.3 Biogenic VOCs -- 5.3.1 General Details -- 5.3.2 Forest Emissions -- 5.3.2.1 Tropical Rainforests -- 5.3.2.2 Coniferous Forests -- 5.3.2.3 Deciduous Forests -- 5.3.2.4 Eddy Covariance Measuring Methodologies -- 5.3.2.5 Forest VOCs and m/z Assignments -- 5.3.3 Plantations -- 5.3.4 Various Land Emissions.

5.3.4.1 Woodland and Grassland Savannahs -- 5.3.4.2 Shrubland -- 5.3.4.3 Alfalfa and Grass Fields -- 5.3.5 Oceans and Seas -- 5.3.5.1 Norwegian Fjord -- 5.3.5.2 Coastal Regions -- 5.3.5.3 Indian Ocean -- 5.3.5.4 Tropical Atlantic Ocean -- 5.4 Anthropogenic VOCs -- 5.4.1 Background -- 5.4.2 VOCs in Urban and Rural Sites -- 5.4.2.1 Innsbruck -- 5.4.2.2 Caracas -- 5.4.2.3 Houston -- 5.4.2.4 Tokyo -- 5.4.2.5 Barcelona -- 5.4.2.6 Manchester and London -- 5.4.2.7 Mexico City -- 5.4.2.8 Toronto and Environs -- 5.4.2.9 Paris -- 5.4.2.10 Boston, New York and Los Angeles -- 5.4.3 Diesel Engine Emissions -- 5.4.4 Aircraft Emissions -- 5.4.5 VOC Emissions Associated with Farming -- 5.4.5.1 Cattle -- 5.4.5.2 Pigs and Sheep -- 5.4.6 Other Studies of Anthropogenic VOCs -- 5.4.6.1 Air Quality -- 5.4.6.2 Firework Emissions -- 5.5 Biomass Burning -- 5.6 Applications of PTR-MS to Laboratory Studies of Atmospheric Chemistry -- 5.6.1 Laboratory Studies of Biomass Burning -- 5.6.2 Reaction Products and Reactive Species -- 5.6.3 Simulation Chamber and Container Measurements -- 5.7 Plant Studies -- 5.7.1 Isoprene Emissions -- 5.7.2 Acetaldehyde Emissions -- 5.7.3 Pollination -- 5.7.4 Roots and Soil -- 5.7.5 Other Plant Studies -- 5.7.5.1 Root-secreted VOCs -- 5.7.5.2 Methanol Release and Bacterial Growth: Plant-Methylobacterium Association -- 5.7.5.3 Comparison of VOC Emissions from Young and Mature Leaves -- 5.7.6 Stress-Related Emissions -- 5.7.7 VOC Emissions Linked to Plant Damage -- 5.7.7.1 Mechanical Wounding -- 5.7.7.2 Weather Damage -- 5.7.7.3 Harvesting and Mowing -- 5.7.7.4 Biofuel Crops -- 5.7.7.5 Herbivore Attack by Small Predators -- 5.7.7.6 Large Herbivore Attack -- 5.7.8 VOC Uptake by Plants -- 5.8 Outlook for Atmospheric and Environmental Applications of PTR-MS -- References -- 6 PTR-MS in the Food Sciences -- 6.1 Background.

6.2 Combined GC-MS and PTR-MS Studies for Food Analysis -- 6.3 Mass Spectral Fingerprinting -- 6.4 Flavour Release and Perception -- 6.4.1 Drinks -- 6.4.1.1 Coffee -- 6.4.1.2 Tea -- 6.4.1.3 Carbonated Drinks -- 6.4.1.4 Fruit Juices -- 6.4.1.5 Wine -- 6.4.1.6 Vodka -- 6.4.1.7 Infant Formula -- 6.4.2 Food -- 6.4.2.1 Cheese -- 6.4.2.2 Bread -- 6.4.2.3 Onions -- 6.4.2.4 Wheys -- 6.4.2.5 Fruit -- 6.4.3 Flavour Release: Food Texture, Composition and Physiological Effects -- 6.5 Food Classification, Food Quality and Food Control -- 6.5.1 Geographical Location -- 6.5.1.1 White Truffles -- 6.5.1.2 Butter -- 6.5.1.3 Olive Oil -- 6.5.1.4 Roe -- 6.5.1.5 Dry-Cured Ham -- 6.5.1.6 Cumin Cheese -- 6.5.2 Food Classification and Quality -- 6.5.3 Food Freshness and Ripening -- 6.5.3.1 Meat Degradation -- 6.5.3.2 Fruit and Vegetables: Ripening, Storage and Monitoring -- 6.5.3.3 Ripening of Cheese -- 6.5.4 Process Monitoring and Biochemical Processing -- 6.6 Outlook for Food Science and Technology Applications -- References -- 7 PTR-MS in the Medical Sciences -- 7.1 Background -- 7.2 Breath Analysis -- 7.2.1 Smoking and Breath Volatiles -- 7.2.2 Isoprene in Breath -- 7.2.3 Acetone in Breath -- 7.2.4 Lung Studies: Cancer and Emphysema -- 7.2.5 Other PTR-MS Breath Studies -- 7.2.5.1 Crohn's Disease and Ulcerative Colitis -- 7.2.5.2 Carbohydrate Malabsorption -- 7.2.5.3 High Mass-Resolution PTR-TOF-MS Breath Studies -- 7.2.5.4 Kidney Function and PTR-MS -- 7.2.5.5 Liver Disease -- 7.2.6 Drug Monitoring and Pharmacokinetics Using Breath Analysis and PTR-MS -- 7.2.7 Breath VOC Levels Measured Using PTR-MS versus Blood Concentrations -- 7.2.8 Breath Sampling and PTR-MS -- 7.2.8.1 Offline Breath Sampling -- 7.2.8.2 Online Breath Sampling -- 7.2.9 PTR-MS and Breath Analysis: Requirements and Future Directions.

7.3 Online PTR-MS Measurements of Volatile Emissions from Microbial Cultures -- 7.3.1 Bacteria -- 7.3.2 VOC Emissions from Fungi -- 7.3.3 Concluding Remarks on Microbial Emissions -- 7.4 Other Medical Applications -- 7.4.1 Urine Headspace Analysis -- 7.4.2 Skin Emissions -- 7.4.3 VOC Emissions from Human Cells -- 7.4.4 VOCs in Clinical Environments -- References -- 8 Applications of PTR-MS to Homeland Security: The Detection of Threat Agents -- 8.1 Background -- 8.2 Explosives -- 8.2.1 Forensic Issues -- 8.2.1.1 The Unambiguous Detection of TNT -- 8.2.1.2 High Mass Resolution PTR-TOF-MS Measurements of TNT -- 8.2.1.3 Reagent Ion Switching and Explosives Detection -- 8.2.1.4 PTR-MS and the Detection of Traces of Explosives -- 8.2.2 Environmental Aspects and Explosives -- 8.3 Chemical Warfare Agents and Toxic Industrial Chemicals -- 8.4 Narcotics -- 8.5 Date Rape Drugs -- 8.6 Ion Mobility Mass Spectrometry and PTR-MS: A Brief Comparison for Homeland Security Applications -- 8.7 Future Directions -- References -- 9 Liquid Analysis Using PTR-MS -- 9.1 Determination of Henry's Law Constants Using PTR-MS -- 9.2 Analysis of Liquids -- References -- Index.