
Isotope Ratio Mass Spectrometry - A Rapidly Developing Tool for Forensic Samples A dissertation presented to the faculty of the College of Arts and Sciences of Ohio University In partial fulfillment of the requirements for the degree Doctor of Philosophy Zeland Muccio March 2010 © 2010 Zeland Muccio. All Rights Reserved. 2 This dissertation titled Isotope Ratio Mass Spectrometry - A Rapidly Developing Tool for Forensic Samples by ZELAND MUCCIO has been approved for the Department of Chemistry and Biochemistry and the College of Arts and Sciences by Glen P. Jackson Associate Professor of Chemistry and Biochemistry Benjamin M. Ogles Dean, College of Arts and Sciences 3 ABSTRACT MUCCIO, ZELAND, Ph.D., March 2010, Chemistry Isotope Ratio Mass Spectrometry - A Rapidly Developing Tool for Forensic Samples (236 pp.) Director of Dissertation: Glen P. Jackson The development of a dual detection system that provides simultaneous structural elucidation and isotopic analyses of forensic samples is described. A gas chromatograph (GC) was coupled to an isotope ratio mass spectrometer (IRMS) in parallel with a single quadrupole mass spectrometer (MS). The modification was achieved by using a low, dead volume x-connector to split the effluent coming from the column so that approximately 10% entered the EI MS and the remaining 90% entered the combustion interface for IRMS. The transfer line that connected the GC to the MS was fabricated to extend the line into the GC oven. Heat tape was tightly wrapped around the extension to maintain a predetermined, constant temperature by use of a manual heat controller. The modified instrumentation was then applied to forensic samples to simultaneously determine the structural elucidation and the isotopic ratios of individual compounds and impurities within the sample. Illicit drugs are one of the most analyzed forensic samples in federal, state, and private forensic laboratories. Cocaine was analyzed and identification was confirmed using a NIST library. The probability scores from the NIST library for all of the cocaine samples ranged between 52.9% and 77.1%. Several cocaine samples were used to determine if the cocaine could have come from the same source using carbon isotopic 4 analysis. Marijuana was another illicit drug that was analyzed using this instrumentation method. We report the first application of GC-IRMS to individual components of Cannabis sativa L. to discriminate between different sources. Different manufacturers, or lot numbers, of common household accelerants such as Goof Off, turpentine, charcoal lighter fluid and WD-40 were also analyzed. The analysis of accelerants demonstrated that this modification of instrumentation could be used for not only pure compounds but, also for very complex compounds. IRMS could distinguish between different sources of accelerants by analyzing trace residues remaining after combustion. To further examine the versatility of this tool, individual amino acids in hair were analyzed. We have shown that it is possible to determine minimally nine individual amino acids within hair samples using a single step derivatization method. In the future, we would like to study single strands of hair and the possibilities of segmenting the hair into sections of monthly growth. The analysis of forensic samples using this modification is virtually unlimited. Approved: _____________________________________________________________ Glen P. Jackson Associate Professor of Chemistry and Biochemistry 5 ACKNOWLEDGMENTS When I first started my graduate degree, I had the pleasure of working with Dr. Vladimir Alexeev. His time working with me was unfortunately cut short but, I do appreciate his wisdom and guidance during the time that we did have together. I will forever remember his carefree nature and his passion for life. I was fortunate enough, during this difficult time, to become associated with Dr. Glen P. Jackson who took me into his research group with open arms. Dr. Jackson was the first one to reach out to me and encourage me to continue when doubts crept into my mind as to whether or not to continue. I truly appreciate the advice and guidance that Dr. Jackson has afforded me during my time in his research group. In addition, was it not for his far superior writing skills, this dissertation would not have come to fruition. I want to thank, Dr. Hao Chen, Dr. Kenneth Brown, and Dr. Shigeru Okada for agreeing to serve on my dissertation committee. I also want to thank Dr. Glen P. Jackson for agreeing to serve as the chair for my committee. I appreciate the time that they took to review my dissertation and provide their learned expertise. I also wish to thank my current lab mates, Shannon Cook, Carolyn Zimmermann, Yan An and former lab mates Derrell Hood, and Dr. Ünige Laskay, for their encouragement and camaraderie. It was always a tremendous help to have them around to help me and talk to. In addition, I had the pleasure of working with a number of very talented undergraduate and exchange students: Christopher Kanalas, Andreas Baum, and Claudia Wöckel. I would like to recognize the entire department of Chemistry and Biochemistry at Ohio University for all of their dedication and hard work, particularly 6 Bascom French and Paul Schmittauer for all of their assistance which allowed my research to progress as it did. I also want to acknowledge the financial assistance received from the National Science Foundation grant number (0745590). Special thanks go out to Dr. Palmer Graves and Dr. Bruce McCord at Florida International University for encouraging me to continue in the field of chemistry and the support that they gave me when I encountered difficulties in my studies. I want to thank Carl Fitzgerald for never losing faith in me and teaching me the values of a good education and the opportunities that it opened up for my future. Finally, and most importantly, I want to sincerely thank Michael Martel, for his endless support and for always being there when I needed him. In the nine years that we have been together he has never once doubted my ability to see this through and I love him dearly for that. And, even if she doesn’t realize it, I want to thank my loving cat Tasha for always welcoming me home and keeping me company! 7 DEDICATION I would first like to dedicate this work to the loving memory of my mother who passed away in 1979. Had circumstances been different, I would have loved for her to have shared my success with me. I would next like to thank my father for continuously encouraging me throughout my education and life. He taught me many things throughout my lifetime and I would like to think that a part of my success was owed to him. Lastly, I want to sincerely thank my brother Frankie, for helping me realize that I could be a better person and make so much more of myself. 8 TABLE OF CONTENTS Page Abstract ............................................................................................................................... 3 Acknowledgments............................................................................................................... 5 Dedication ........................................................................................................................... 7 List of Tables .................................................................................................................... 13 List of Figures ................................................................................................................... 14 List of Abbreviations ........................................................................................................ 18 Chapter 1: Introduction ..................................................................................................... 20 1.1 Objective ................................................................................................................. 20 1.2 Project Overview .................................................................................................... 21 1.3 Instrumentation ....................................................................................................... 24 Chapter 2: Isotope Ratio Mass Spectrometry ................................................................... 26 2.1 Introduction ............................................................................................................. 26 2.1.1 EA-IRMS ......................................................................................................... 32 2.1.2 GC-IRMS ......................................................................................................... 33 2.1.3 LC-IRMS ......................................................................................................... 34 2.2 Origins of variations in isotopic abundances .......................................................... 35 2.3 Applications ............................................................................................................ 38 2.3.1 Forensic ............................................................................................................ 38 2.3.2 Food and Drugs ................................................................................................. 42 2.3.3 Diet, Biochemistry and Metabolism ................................................................. 45 9 2.3.4 Athletics and Doping ........................................................................................ 49 2.3.5 Environmental Pollution .................................................................................
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