Analysis. TOF-MS within Food and Environmental. Comprehensive Analytical Chemistry. Volume 58. Amadeo R. Fernandez-Alba

Transcription

1 _ SAN LONDON NEW TOF-MS within Food and Environmental Analysis Comprehensive Analytical Chemistry Volume 58 Amadeo R. Fernandez-Alba Department of Hydrogeology and Analytical Chemistry, European Union Reference Laboratory (DG SANCO) for Residues of Pesticides in Fruits and Vegetables, University of Almeria AMSTERDAM BOSTON HEIDELBERG OT_ rr^t-, JiLSJiVlJtlK PARIS DIEGO SAN FRANCISCO SINGAPORE SYDNEY TOKYO YORK OXFORD

2 Contents Contributors to Volume 58 Series Editor Preface Volume Editor Preface XVII xix xxi 1. Application of HPLC-TOF-MS and HPLC-QTOF-MS/MS for Pesticide Residues Analysis in Fruit and Vegetable Matrices 1 Carmen Ferrer, Octavio Malato, Ana Aguera, R. Fernandez-Alba and Amadeo 1. Introduction and Scope 1 2. Advantages of the Accurate Mass 4 3. Accurate Mass Databases and Automatic Searching Applications of HPLC-TOF-MS for Multiresidue Analysis of Pesticides in Fruits and Vegetables Target Analysis Nontarget Analysis Multiresidue Methods Based on Sequential TOF-MS and QTOF-MS/MS Conclusions and Future Trends 55 Acknowledgments 56 References Chemical Evaluation of Water Treatment Processes by LC-(Q)TOF-MS: Identification of Transformation Products 61 Ana Aguera, Maria del Mar Gomez Ramos, and Amadeo R. Fernandez-Alba 1. Introduction TPs in Wastewater Treatments Sampling and Sample Preparation Chromatographic Separation Identification and Structural Elucidation Strategies for Identification and Structural Elucidation of TPs by LC-(Q)TOF-MS: Practical Aspects Calculation of the Elemental Composition Use of Fragmentation Pathways Isotope Abundance Measurements 89 xi

3 Contents 4. Selected Applications of LC-(Q)TOF-MS in Water Treatment Processes: Transformation Pathways Biological Treatments Ozonation and Advanced Oxidation Processes Conclusions 101 Acknowledgments 102 References 102 of Accurate Mass Determinations 3. Selected Applications Using LC-TOF for Toxic Compounds in Products of Animal Origin 111 Perry Martos and Heather McCormick 1. Accurate Mass Determinations Data Interpretation Additional Statistical Tests Conclusions Case Study 1: Injectable Solution of Oxytetracycline Contaminated with a Suspect Sulfonamide Experimental Results Conclusions Case Study 2: Green-Eyed Dog and Rhodamine Dye Conclusions Case Study 3: Thirty-Six Dead Birds and Contaminated Seeds Method Results Conclusions Overall Considerations and Conclusions 163 References High Mass Resolution Versus MS/MS 169 Anton Kaufmann 1. Introduction A Personal Experience Basic Principle of Modern HRMS Instruments Time of Flight Orbitrap Selectivity Selectivity Requirements for Residue Analysis Isobaric Interferences a HRMS Problem Which HRMS Resolution Provides MS/MS Selectivity? The Price to be Paid for High Mass Resolution 186 Limitations Reported LC-MS Selectivity 3.6 The Need for Higher Selectivity MS/MS Instrumentation 189

4 4. Sensitivity Comparing MS/MS to HRMS Sensitivity Orbitrap- and TOF-Specific Sensitivity Issues Different Characteristics of Analog Versus Digital Detector Noise Quantitative Performance General Quantification Performance Orbitrap-Specific Suppression Effects Comparing HRMS Versus MS/MS Quantification Performance Confirmation False Positive and False Negative Findings by MS/MS Comparing HRMS to MS/MS Confirmatory Performance Confirmation Based on Nonprecursor Selected Ion Ratio 20O 6.4 Possibilities and Limitations of Current HRMS-Based Confirmation Techniques Identification of Unknowns Importance of Accurate Masses and Isotopic Abundances Detecting Specific Moieties or Atoms by HRMS Comprehensiveness of Detection Conclusion 210 References Time-of-Flight Mass Spectrometry Versus Orbitrap-Based Mass Spectrometry for the Screening and Identification of Drugs and Metabolites: Is There a Winner? Peter Eichhorn, Sandra Perez, and Damia Barcelo 1. Introduction (The Race) 2. Fundamentals and Characteristics of Orbitrap Technology (Presentation of the Challenger) 3. From Theory to Practice (Track-and-Field Championship) 3.1 Environmental Analysis (Exercising in a Pristine World?) 3.2 Food Analysis (Meeting the Nutritional Needs of the Contestants) 3.3 In Vitro Drug Metabolism Studies (Inside the Athlete's Body) 3.4 Doping Control and Forensic Drug Screening (Checking for Unfair Competition) 4. Conclusions (Award Ceremony: The Winner Is..,) References Electrospray Operational Parameters in TOF-MS 273 Thomas Clauner and A. Paul Zavitsanos 1. Introduction 2. Theory

5 (^xiv~^) Contents 2.1 Fundamentals of a TOF Analyzer Reference Mass Correction Sample 3. Experimental 280 and Reference Mass Introduction and Ionization Instrumental Parameters Optimization of Agilent Jet Stream Parameters for Pesticide Analysis Optimization of Reference Mass Introduction for Samples with Complex Matrices Results and Discussion Optimization of Agilent Jet Stream Parameters Optimization of Reference Mass Introduction for Samples with Complex Matrices Pesticide Screening in Complex Matrices Under Optimized Conditions Summary and Conclusion 301 Acknowledgments 303 References MALDI-TOF MS for Characterization of Synthetic Polymers in Aqueous Environment 307 Ian Ken D. Dimzon and Thomas P. Knepper 1. Introduction General Aspects of MS in Polymer Analysis MS of Large Molecules MALDI Process MALDI Sample Preparation Hyphenation of MALDI and TOF MALDI-TOF Spectrum as an ESI-q Alternative Method Chromatographic Separation Prior to MS Illustration: MALDI-TOF MS of Chitosan Oligosaccharide Future of MALDI-TOF in Polymer Analysis: Fate and Degradation Studies 331 Acknowledgment 335 References The Potential of Ambient Desorption Ionization Methods Combined with High-Resolution Mass Spectrometry for Pesticide Testing in Food 339 Juan F. Carcfa-Reyes, Bienvenida Gilbert-Lopez, Ana Aguera, Amadeo R. Fernandez-Alba, and Antonio Molina-Dfaz 1. Introduction 339

6 Contents 2. Ambient MS Techniques Used for Testing of Pesticides and Other Contaminant Residues DART-MS Applied to Pesticide Testing in Food DESI-MS Applied for Pesticide Testing in Food Other Ambient MS Methods for Pesticide Testing and Food Safety Screening Concluding Remarks 363 Acknowledgments 363 References 363 of GC-TOFMS for Pesticide Residue 9. Application Analysis in Grapes 367 Kaushik Banerjee, Soma Dasgupta, and Sagar C. Utture 1. Introduction The Analytical Problems Associated with Pesticide Residue Analysis in Crapes Improvement in Mass Spectral Detection by Using TOF Improving the Chromatographic Separation-Possible with TOFMS Development of a Robust Method for Pesticide Residue Analysis in Grapes Sample Preparation Extraction of Pesticides from Grapes Sample Preparation Extraction of Pesticides from Wine Sample Preparation Extraction of Pesticides from Grape Juice The Development of Robust Chromatographic Conditions Comparative Appraisal of S/N in 1D (GC-TOFMS) with 2D (GC x GC-TOFMS) Application of the Optimized GCx GC-TOFMS Method for Residue Monitoring in Grapes Application of the Optimized GCx GC-TOFMS Method for Residue Monitoring 8. Screening for Nontarget Analytes 402 in Wine Evaluation of GC x GC-TOFMS vis-a-vis GC-MS/MS Conclusion and Future Perspectives 409 Acknowledgment 410 References 412 Subject Index 415