UNIVERSITY OF CINCINNATI Date: May 14, 2007 I, Douglas Dennis Richardson II , hereby submit this work as part of the requirements for the degree of: Doctor of Philosophy (Ph.D) in: Chemistry It is entitled: Modern Advancements in Elemental Speciation: From Sample Introduction to Chemical Warfare Agent Detection This work and its defense approved by: Chair: Dr. Joseph A. Caruso Dr. William R. Heineman Dr. James Mack Modern Advancements in Elemental Speciation: From Sample Introduction to Chemical Warfare Agent Detection A dissertation submitted to the Division of Research and Advanced Studies of the University of Cincinnati In partial fulfillment of the requirements for the degree of Doctor of Philosophy (Ph.D) In the Department of Chemistry of the McMicken College of Arts and Sciences 2007 By Douglas Dennis Richardson II B.S., Forensic Chemistry, Ohio University, 2003 M.S. Chemistry, University of Cincinnati, 2006 Committee Chair: Dr. Joseph A. Caruso Abstract of Dissertation Elemental speciation is the investigation of the chemical form of metal and non- metal containing species in environmental and biological systems for the determination of species specific essentiality and toxicity. Speciation analysis is performed by combining modern separation techniques with state-of-the-art element specific mass spectrometry. Separation techniques used in this work include: capillary electrophoresis (CE), high performance liquid chromatography (HPLC) and gas chromatography (GC). Inductively coupled plasma mass spectrometry (ICPMS) is the instrument of choice for ultra-trace elemental speciation analyses due to the excellent sensitivity and selectivity specific to this mass spectrometer. Modern innovations in analytical instrumentation specific for elemental speciation have provided researchers with resources for the development of new hyphenated techniques and analytical methods. The specific goal of this dissertation is to describe modern advancements specific to elemental speciation. In the first section a novel interface coupling CE and hydride generation with ICPMS detection for arsenic speciation is described. The novel concentric tube interface design allowed for the separation, hydride generation, and detection of four arsenic species in less than 10 minutes. The majority of this dissertation focuses on method development for the analysis of organophosphorus chemical warfare agent (CWA) degradation products. Recent increases in worldwide terrorist activity as well as the threat of chemical weapon attacks have led to the demand for rapid and reliable analytical techniques for CWA analysis. Methods utilizing both HPLC and GC separation techniques couple with 31P element ii specific detection with ICPMS for the analysis of organophosphorus chemical warfare agent degradation products are described. These works are the first to utilize 31P detection with ICPMS for the analysis of chemical warfare agent degradation products. iii Acknowledgments This dissertation is dedicated to my parents Douglas and Rebecca Richardson, without whom none of my educational accomplishments would have been possible. They have always been there to provide spiritual, educational, and monetary support without too many questions. I would also like to acknowledge my siblings Katie, Jon, Chris, and my dog Rocky for their continued support and harassment. The completion of this degree would not have been possible without the support of my friend and advisor Dr. Joseph Caruso (“Doc”). His willingness to take risks as well as deal with scientific setbacks and breakthroughs in a relaxed manner is a characteristic that I plan to model my career after. Dr. Caruso has provided me with multiple opportunities for both academic and personal growth for which I am forever thankful. In addition Dr. Caruso and his wife Judy have treated me like a son throughout my time in Cincinnati, and this relationship is more valuable to me than any academic degree. I would like to thank my committee members Dr. William R. Heineman and Dr. James Mack for all their scientific challenges and teachings throughout my graduate school experience. Also, thanks to the analytical faculty; Dr. Patrick A. Limbach, Dr. Tom Ridgway, and Dr. Apryll Stalcup for all their support. None of my research would have been possible without the excellent people behind the scenes Kim Carey, John Zureick, Betty Ligon, Cassandra McGee, and Jamie Cartwright. A special thanks to Dr. Sasi Kannamkumarath, Dr. Rodolfo Wuilloud, Dr. Baki Sadi, and Dr. Monika Shah for teaching me everything they (I) know about ICPMS. To the Caruso group members Dr. Sandra Mounicou, Dr. Juris Meija, Dr. Tyre Grant, Dr. Katie DeNicola, Kevin Kubachka, Kirk Lokits, Heather Trenary, Scott Afton, Jenny Ellis, Karolin Kroning, and all other iv group members past and present, it was a pleasure working with you all. To my fellow graduate students and friends Stuart Willison, Michael Haven, Phil Durham, Kevin Parker, Dr. Justin Mecomber, Adam Bange, Becky Rolfs, Kady Krivos, Susan Russell, and Colette Castleberry you have made my time in the chemistry department fun and exciting and you all will be missed. To my Australian friends Emeritus Professor David Knowles and Dr. Anne McLachlan (Macca) it has been my pleasure getting to know you both. You have helped opened my eyes to the entire world and I value our friendship deeply. A special thanks to Agilent Technologies specifically Toshiaki Matsuda, Steve Wilbur, Don Potter, Steve Miller, and Ron Sanderson. The University of Cincinnati/Agilent Metallomics Center of the Americas is alive and well thanks to your support. Other scientist and collaborators with whom I have had the pleasure of interacting include; Dr. Fred Fricke (FDA), Dr. Doug Heitkemper (FDA), Dr. Jack Creed (EPA), Dr. Brian Gamble (FDA), Dr. Ray Warren (P&G), Dr. Wendy Qin (P&G), Brian Gray (P&G), and Dr. John Hammons (P&G). Last but certainly not least I must thank my best friend Daisy-Malloy Hamburg. You have supported me throughout the emotional rollercoaster ride of graduate school allowing our relationship to blossom along the way. Remember we are like electrons of opposite spin impossible to keep apart and I look forward to many more adventures together. I love you babe! -DDR v Table of Contents Abstract of Dissertation ii Acknowledgments iv Table of Contents 1 Figures 4 Tables 7 Chapter 1 – Elemental Speciation with Inductively Coupled Plasma Mass Spectrometry 1.1 Overview 1.2 Inductively Coupled Plasma Mass Spectrometry (ICPMS) 1.2.1 Sample Introduction 1.2.1.1 Liquid Sample Introduction 1.2.1.2 Hydride Generation 1.2.2 Plasma Ionization Source 1.2.3 Interference Removal with Collision/Reaction Cell 1.2.3 Mass Spectrometric Detection 1.3 Elemental Speciation Techniques 1.3.1 Capillary Electrophoresis (CE) with ICPMS 1.3.2 High Performance Liquid Chromatography (HPLC) with ICPMS 1.3.2.1 Reversed Phase Chromatography 1.3.2.2 Ion-Pairing Chromatography 1.3.3 Gas Chromatography (GC) with ICPMS 1.3.3.1 Interfacing GC with ICPMS 1.3.3.2 Sample Introduction Techniques for GC with ICPMS 1.4 References Chapter 2- Hydride Generation Interface for Speciation Analysis Coupling Capillary Electrophoresis to Inductively Coupled Plasma Mass Spectrometry 2.1 Abstract 2.2 Introduction 2.3 Experimental 2.3.1 Reagents 2.3.2 Instrumentation 2.3.3 Interface Design 2.3.4 Coupling Hydride Generation Interface with ICPMS 2.4 Results and Discussion 2.4.1 Optimization of Hydride Generation Conditions 2.4.2 Arsenic Species Separation by Capillary Electrophoresis 1 2.4.3 Analytical Performance of CE-HG-ICPMS 2.4.4 Arsenic Speciation in Water Samples 2.5 Conclusion 2.6 Acknowledgments 2.7 References Chapter 3- Reversed phase ion-pairing HPLC-ICPMS for analysis of organophosphorus chemical warfare agent degradation products 3.1 Abstract 3.2 Introduction 3.3 Experimental 3.3.1 Reagents 3.3.2 Instrumentation 3.3.2.1 HPLC 3.3.2.2 ICPMS 3.3.2.3 Electrospray Mass Spectrometry (ESI-MS) 3.4 Results and Discussion 3.4.1 Ion-pairing HPLC 3.4.2 ICPMS Detection 3.4.3 Analytical Figure of Merit 3.4.4 Complex Samples 3.4.5 Characterization Efforts 3.5 Conclusion 3.6 Acknowledgments 3.7 References Chapter 4- Derivatization of Organophosphorus Nerve Agent Degradation Products for Gas Chromatography with ICPMS and GC-ToF Detection 4.1 Abstract 4.2 Introduction 4.3 Experimental 4.3.1 Reagents 4.3.2 Derivatization 4.3.3 Environmental Samples 4.4 Instrumentation 4.4.1 Gas Chromatography (GC) 4.4.2 ICPMS 4.4.3 Gas Chromatography-Time of Flight Mass Spectrometry (GC-ToF) 4.5 Results and Discussion 4.5.1 GC-ICPMS 4.5.2 GC-ToF 4.5.3 Analytical Figures of Merit 4.5.4 Phosphate and Environmental Samples 4.6 Conclusion 2 4.7 Acknowledgments 4.8 References Chapter 5- Screening Organophosphorus Nerve Agent Degradation Products in Pesticide Mixtures by GC-ICPMS 5.1 Abstract 5.2 Introduction 5.3 Experimental 5.3.1 Reagents 5.3.2 Sample Preparation 5.4 Instrumentation 5.4.1 Gas Chromatography (GC) 5.4.2 ICPMS 5.5 Results and Discussion 5.5.1 GC-ICPMS 5.5.2 Pesticide Analysis in Nerve Agent Degradation Product Mixture 5.5.3 Degradation Product Analysis in Pesticide Mixtures 5.6 Conclusion 5.7 Acknowledgments 5.8 References Chapter 6- Conclusions and Future Directions 3 Figures 1.1- Experimental considerations for elemental speciation analysis. 1.2- Instrument schematic for an Agilent 7500ce ICPMS. 1.3- Concentric nebulizer design for liquid sample introduction. 1.4- General “ABC” pathway for hydride generation by borohydride reduction. 1.5- Schematic of an inductively coupled plasma torch. 1.6- Plasma ionization pathway. 1.7- Agilent Technologies collision/reaction cell for 7500ce ICPMS. 1.8- Interference removal through collision induced dissociation and KED. 1.9- Electron multiplier (detector) for Agilent 7500ce ICPMS. 1.10- Equations for calculating electrophoretic mobility of analytes in CE. 1.11- Diagram of capillary wall and bulk electrolyte flow (EOF).