Analytical Chemistry

About the Authors xxiii Preface xxv Acknowledgments xxvii About the Companion Website xxviii 1 Chemist and Technician in the Analytical Laboratory 1 1.1 Introduction—The Analytical Chemist and Technician 1 1.2 Today’s Laboratory Chemist and Technician 1 1.3 ChemTech—The Chemist and Technician Toolkit Companion 2 1.4 Chapter Layout 2 1.5 Users of ChemTech 6 2 Introduction to the Analytical Laboratory 7 2.1 Introduction to the Laboratory 7 2.2 Laboratory Glassware 7 2.3 Conclusion 18 3 Laboratory Safety 19 3.1 Introduction 19 3.2 Proper Personal Protection and Appropriate Attire 19 3.3 Proper Shoes and Pants 20 3.4 Laboratory Gloves 20 3.5 General Rules to Use Gloves 22 3.6 Safety Data Sheet (SDS) 22 3.7 Emergency Eyewash and Face Wash Stations 24 3.8 Emergency Safety Showers 25 3.9 Fire Extinguishers 25 3.10 Clothing Fire in The Laboratory 26 3.11 Spill Cleanup Kits 26 3.12 Chemicals and Solvents 27 3.13 First Aid Kits 29 3.14 Gasses and Cylinders 29 3.15 Sharps Containers and Broken Glass Boxes 30 3.16 Occupational Safety and Health Administration (OSHA) 30 4 Basic Mathematics in the Laboratory 83 4.1 Introduction to Basic Math 83 4.2 Units and Metric System 83 4.3 Significant Figures 84 4.4 Scientific Calculators 86 4.5 ChemTech Conversion Tool 89 4.6 Chapter Key Concepts 96 4.7 Chapter Problems 96 5 Analytical Data Treatment (Statistics) 97 5.1 Errors in the Laboratory 97 5.2 Expressing Absolute and Relative Errors 98 5.3 Precision 98 5.4 The Normal Distribution Curve 98 5.5 Precision of Experimental Data 100 5.6 Normal Distribution Curve of a Sample 101 5.7 ChemTech Statistical Calculations 102 5.8 Student’s Distribution t Test for Confidence Limits 105 5.9 Tests of Significance 111 5.10 Treatment of Data Outliers 112 5.11 Chapter Key Concepts 114 5.12 Chapter Problems 114 6 Plotting and Graphing 116 6.1 Introduction to Graphing 116 6.2 Graph Construction 116 6.3 Rectangular Cartesian Coordinate System 117 6.4 Curve Fitting 117 6.5 Redrawn Graph Example 117 6.6 Graphs of Equations 118 6.7 Least-Squares Method 121 6.8 Computer-Generated Curves 122 6.9 Calculating Concentrations 125 6.10 Nonlinear Curve Fitting 126 6.11 Chapter Key Concepts 130 6.12 Chapter Problems 130 7 Using Microsoft Excel® in the Laboratory 132 7.1 Introduction to Excel® 132 7.2 Opening Excel in ChemTech 132 7.3 The Excel Spreadsheet 132 7.4 Graphing in Excel 134 7.5 Complex Charting in Excel 137 7.6 Statistical Analysis using Excel 139 8 Making Laboratory Solutions 151 8.1 Introduction 151 8.2 Laboratory Reagent Fundamentals 151 8.3 The Periodic Table 151 8.4 Calculating Formula Weights 152 8.5 Calculating The Mole 152 8.6 Molecular Weight Calculator 152 8.7 Expressing Concentration 153 8.8 The Parts PER (PP) Notation 157 8.9 Computer-Based Solution Calculations 157 8.10 Reactions in Solution 161 8.11 Chapter Key Concepts 161 8.12 Chapter Problems 162 9 Acid–Base Theory and Buffer Solutions 163 9.1 Introduction 163 9.2 Acids and Bases in Everyday Life 163 9.3 The Litmus Test 163 9.4 Early Acid–Base Descriptions 164 9.5 Brǿnsted–Lowry Definition 164 9.6 The Equilibrium Constant 165 9.7 The Acid Ionization Constant 165 9.8 Calculating the Hydrogen Ion Concentration 165 9.9 The Base Ionization Constant 167 9.10 Ion Product for Water 168 9.11 The Solubility Product Constant (K SP) 168 9.12 The pH of a Solution 170 9.13 Measuring the pH 171 9.14 Buffered Solutions—Description and Preparing 172 9.15 ChemTech Buffer Solution Calculator 174 9.16 Chapter Key Concepts 175 9.17 Chapter Problems 175 10 Titration—A Volumetric Method of Analysis 178 10.1 Introduction 178 10.2 Reacting Ratios 178 10.3 The Equivalence Point 179 10.4 Useful Relationships for Calculations 179 10.5 Deriving the Titration Equation 179 10.6 Titrations in ChemTech 180 10.7 Acid/Base Titration Endpoint (Equivalence Point) 181 10.8 Acid/Base Titration Midpoint 182 10.9 Acid/Base Titration Indicators 182 10.10 Titrations Using Normal Solutions 184 10.11 Polyprotic Acid Titration 184 10.12 ChemTech Calculation of Normal Titrations 185 10.13 Performing a Titration 185 10.14 Primary Standards 186 10.15 Standardization of Sodium Hydroxide 187 10.16 Conductometric Titrations (Nonaqueous Solutions) 189 10.17 Precipitation Titration (MOHR Method for Halides) 190 10.18 Complex Formation with Back Titration (Volhard Method for Anions) 191 10.19 Chapter Key Concepts 196 10.20 Chapter Problems 197 11 Oxidation–Reduction (Redox) Reactions 199 11.1 Introduction 199 11.2 Oxidation and Reduction 199 11.3 The Volt 200 11.4 The Electrochemical Cell 200 11.5 Redox Reaction Conventions 200 11.6 The Nernst Equation 202 11.7 Determining Redox Titration Endpoints 203 11.8 Potentiometric Titrations 204 11.9 Visual Indicators used in Redox Titrations 206 11.10 Pretitration Oxidation–Reduction 207 11.11 Ion-Selective Electrodes 207 11.12 Chapter Key Concepts 207 11.13 Chapter Problems 209 12 Laboratory Information Management System (LIMS) 211 12.1 Introduction 211 12.2 Lims Main Menu 211 12.3 Logging in Samples 213 12.4 Entering Test Results 213 12.5 Add or Delete Tests 214 12.6 Calculations and Curves 214 12.7 Search Wizards 215 12.8 Approving Samples 217 12.9 Printing Sample Reports 217 13 Ultraviolet and Visible (UV/VIS) Spectroscopy 227 13.1 Introduction to Spectroscopy in the Analytical Laboratory 227 13.2 The Electromagnetic Spectrum 227 13.3 Ultraviolet/Visible (UV/VIS) Spectroscopy 227 13.4 UV/Visible Spectrophotometers 236 13.5 Special Topic (Example)—Spectrophotometric Study of Dye Compounds 237 13.6 Chapter Key Concepts 240 13.7 Chapter Problems 242 14 Fluorescence Optical Emission Spectroscopy 244 14.1 Introduction to Fluorescence 244 14.2 Fluorescence and Phosphorescence Theory 245 14.3 Phosphorescence 246 14.4 Excitation and Emission Spectra 247 14.5 Rate Constants 247 14.6 Quantum Yield Rate Constants 248 14.7 Decay Lifetimes 248 14.8 Factors Affecting Fluorescence 249 14.9 Quantitative Analysis and Beer–Lambert Law 252 14.10 Quenching of Fluorescence 253 14.11 Fluorometric Instrumentation 253 14.12 Special Topic—Fluorescence Study of Dye-A007 Complexes 259 14.13 Chapter Key Concepts 261 14.14 Chapter Problems 262 15 Fourier Transform Infrared (FTIR) Spectroscopy 264 15.1 Introduction 264 15.2 Basic IR Instrument Design 264 15.3 The Infrared Spectrum and Molecular Assignment 266 15.4 FTIR Table Band Assignments 267 15.5 FTIR Spectrum Example I 273 15.6 FTIR Spectrum Example II 273 15.7 FTIR Inorganic Compound Analysis 274 15.8 Chapter Key Concepts 274 15.9 Chapter Problems 276 16 Nuclear Magnetic Resonance (NMR) Spectroscopy 280 16.1 Introduction 280 16.2 Frequency and Magnetic Field Strength 280 16.3 Continuous-Wave NMR 281 16.4 The NMR Sample Probe 282 16.5 Pulsed-Field Fourier Transform NMR 282 16.6 Proton NMR Spectra Environmental Effects 284 16.7 Carbon-13 NMR 286 16.8 Special Topic—NMR Characterization of Cholesteryl Phosphate 290 16.9 Chapter Key Concepts 295 16.10 Chapter Problems 296 References 297 17 Atomic Absorption Spectroscopy (AAS) 298 17.1 Introduction 298 17.2 Atomic Absorption and Emission Process 298 17.3 Atomic Absorption and Emission Source 299 17.4 Source Gases and Flames 299 17.5 Block Diagram of AAS Instrumentation 299 17.6 The Light Source 301 17.7 Interferences in AAS 302 17.8 Electrothermal Atomization—Graphite Furnace 302 17.9 Instrumentation 303 17.10 Flame Atomic Absorption Analytical Methods 304 18 Atomic Emission Spectroscopy 306 18.1 Introduction 306 18.2 Elements in Periodic Table 306 18.3 The Plasma Torch 306 18.4 Sample Types 307 18.5 Sample Introduction 308 18.6 ICP-OES Instrumentation 308 18.7 ICP-OES Environmental Application Example 313 19 Atomic Mass Spectrometry 328 19.1 Introduction 328 19.2 Low-Resolution ICP-MS 328 19.3 High-Resolution ICP-MS 331 20 X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) 336 20.1 X-Ray Fluorescence Introduction 336 20.2 X-Ray Fluorescence Theory 336 20.3 Energy-Dispersive X-Ray Fluorescence (EDXRF) 337 20.4 Wavelength Dispersive X-Ray Fluorescence (WDXRF) 340 20.5 Applications of XRF 344 20.6 X-Ray Diffraction (XRD) 345 21 Chromatography—Introduction and Theory 354 21.1 Preface 354 21.2 Introduction to Chromatography 354 21.3 Theory of Chromatography 354 21.4 The Theoretical Plate Number N 358 21.5 Resolution Rs 359 21.6 Rate Theory Versus Plate Theory 360 21.7 Retention Factor k′ 365 References 365 22 High-Performance Liquid Chromatography (HPLC) 366 22.1 HPLC Background 366 22.2 Design and Components of HPLC 366 23 Solid-Phase Extraction 383 23.1 Introduction 383 23.2 Disposable SPE Columns 383 23.3 SPE Vacuum Manifold 383 23.4 SPE Procedural Bulletin 383 24 Plane Chromatography: Paper and Thin-Layer Chromatography 397 24.1 Plane Chromatography 397 24.2 Thin-Layer Chromatography 398 24.3 Retardation Factor (R F) In TLC 399 24.4 Plate Heights (H) and Counts (N) In TLC 400 24.5 Retention Factor In TLC 401 25 Gas-Liquid Chromatography 402 25.1 Introduction 402 25.2 Theory and Principle of GC 402 25.3 Mobile-Phase Carrier Gasses in GC 404 25.4 Columns and Stationary Phases 405 25.5 Gas Chromatograph Injection Port 407 25.6 The GC Oven 415 25.7 GC Programming and Control 418 25.8 GC Detectors 419 26 Gas Chromatography–Mass Spectrometry (GC–MS) 422 26.1 Introduction 422 26.2 Electron Ionization (EI) 422 26.3 Electron Ionization (EI)/OE Processes 423 26.4 Oleamide Fragmentation Pathways: OE M +⋅ by Gas Chromatography/Electron Ionization Mass Spectrometry 426 26.5 Oleamide Fragmentation Pathways: EE [M+H] + by ESI/ION Trap Mass Spectrometry 427 26.6 Quantitative Analysis by GC/EI–MS 430 26.7 Chapter Problems 432 References 434 27 Special Topics: Strong Cation Exchange Chromatography and Capillary Electrophoresis 436 27.1 Introduction 436 27.2 Strong Ion Exchange HPLC 436 27.3 Cze 436 27.4 Binding Constants by Cation Exchange and CZE 437 27.5 Comparison of Methods 446 27.6 Conclusions 449 References 449 28 Mass Spectrometry 450 28.1 Definition and Description of Mass Spectrometry 450 28.2 Basic Design of Mass Analyzer Instrumentation 450 28.3 Mass Spectrometry of Protein Metabolite and Lipid Biomolecules 452 28.4 Fundamental Studies of Biological Compound Interactions 456 28.5 Mass-to-Charge (m/z) Ratio: How the Mass Spectrometer Separates Ions 457 28.6 Exact Mass Versus Nominal Mass 459 28.7 Mass Accuracy and Resolution 460 28.8 High-Resolution Mass Measurements 462 28.9 Rings Plus Double Bonds (r+db) 464 28.10 The Nitrogen Rule in Mass Spectrometry 465 28.11 Chapter Problems 466 References 466 29 Ionization in Mass Spectrometry 468 29.1 Ionization Techniques and Sources 468 29.2 Chemical Ionization (CI) 468   29.3 Atmospheric Pressure Chemical Ionization (APCI) 472 29.4 Electrospray Ionization (ESI) 474 29.5 Nanoelectrospray Ionization (NANO-ESI) 476 29.6 Atmospheric Pressure Photoionization (APPI) 479 29.7 Matrix-Assisted Laser Desorption Ionization (MALDI) 484 29.8 Fab 486 29.9 Chapter Problems 490 References 490 30 Mass Analyzers in Mass Spectrometry 492 30.1 Mass Analyzers 492 30.2 Magnetic and Electric Sector Mass Analyzer 492 30.3 Time-of-Flight Mass Analyzer (TOF/MS) 496 30.4 Time-of-Flight/Time-of-Flight Mass Spectrometer (TOF–TOF/MS) 498 30.5 Quadrupole Mass Filter 500 30.6 Triple Quadrupole Mass Spectrometer (QQQ/MS) 503 30.7 Three-Dimensional Quadrupole Ion Trap Mass Spectrometer (QIT/MS) 504 30.8 Linear Quadrupole Ion Trap Mass Spectrometer (LTQ/MS) 506 30.9 Quadrupole Time-of-Flight Mass Spectrometer (Q-TOF/MS) 508 30.10 Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (fticr/ms) 509 30.11 Linear Quadrupole Ion Trap Fourier Transform Mass Spectrometer (ltq–ft/ms) 517 30.12 Linear Quadrupole Ion Trap Orbitrap Mass Spectrometer (LTQ–Orbitrap/MS) 519 30.13 Chapter Problems 527 References 528 31 Biomolecule Spectral Interpretation: Small Molecules 529 31.1 Introduction 529 31.2 Ionization Efficiency of Lipids 529 31.3 Fatty Acids 530 31.4 Wax Esters 538 31.5 Sterols 542 31.6 Acylglycerols 547 31.7 Esi-Mass Spectrometry of Phosphorylated Lipids 550 31.8 Chapter Problems 556 References 557 32 Macromolecule Analysis 559 32.1 Introduction 559 32.2 Carbohydrates 559 32.3 Nucleic Acids 565 32.4 Chapter Problems 576 References 576 33 Biomolecule Spectral Interpretation: Proteins 577 33.1 Introduction to Proteomics 577 33.2 Protein Structure and Chemistry 577 33.3 Bottom-Up Proteomics: Mass Spectrometry of Peptides 578 33.4 Top-Down Proteomics: Mass Spectrometry of Intact Proteins 588 33.5 PTM of Proteins 592 33.6 Systems Biology and Bioinformatics 610 33.7 Chapter Problems 614 References 616 Appendix I: Chapter Problem Answers 619 Appendix II: Atomic Weights and Isotopic Compositions 625 Appendix III: Fundamental Physical Constants 629 Appendix IV: Redox Half-Reactions 630 Appendix V: Periodic Table of Elements 633 Appendix VI: Installing and Running Programs 635 Index 637