Florida International University FIU Digital Commons FIU Electronic Theses and Dissertations University Graduate School 3-23-2010 The evelopmeD nt of High Performance Liquid Chromatography Systems for the Analysis of Improvised Explosives Megan N. Bottegal Florida International University, [email protected] DOI: 10.25148/etd.FI10041603 Follow this and additional works at: https://digitalcommons.fiu.edu/etd Recommended Citation Bottegal, Megan N., "The eD velopment of High Performance Liquid Chromatography Systems for the Analysis of Improvised Explosives" (2010). FIU Electronic Theses and Dissertations. 154. https://digitalcommons.fiu.edu/etd/154 This work is brought to you for free and open access by the University Graduate School at FIU Digital Commons. It has been accepted for inclusion in FIU Electronic Theses and Dissertations by an authorized administrator of FIU Digital Commons. For more information, please contact [email protected]. FLORIDA INTERNATIONAL UNIVERSITY Miami, Florida THE DEVELOPMENT OF OPTIMIZED HIGH PERFORMANCE LIQUID CHROMATOGRAPHY SYSTEMS FOR THE ANALYSIS OF IMPROVISED EXPLOSIVES A dissertation submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY in CHEMISTRY by Megan Nicole Bottegal 2010 To: Dean Kenneth Furton College of Arts and Sciences This dissertation, written by Megan Nicole Bottegal, and entitled The Development of Optimized High Performance Liquid Chromatography Systems for the Anlysis of Improvised Explosives, having been approved in respect to style and intellectual content, is referred to you for judgment. We have read this dissertation and recommend that it be approved. ____________________________________ Jose Almirall ____________________________________ John Berry ____________________________________ William Hearn ____________________________________ Fenfei Leng ____________________________________ DeEtta Mills ____________________________________ Bruce McCord, Major Professor Date of Defense: March 23, 2010 The dissertation of Megan Nicole Bottegal is approved. ____________________________________ Dean Kenneth Furton College of Arts and Sciences ____________________________________ Interim Dean Kevin O’Shea University Graduate School Florida International University, 2010 ii © Copyright 2010 by Megan Nicole Bottegal All rights reserved. iii DEDICATION I dedicate this dissertation to my parents. Without their love, patience, generosity, and guidance, the completion of this work would have been impossible. iv ACKNOWLEDGMENTS I would like to thank the members of my dissertation committee for their support and assistance. Dr. Bruce McCord granted me the opportunities to conduct interesting research, to learn new analytical techniques, and to attend a variety of conferences and meetings. Dr. Jose Almirall first encouraged me to attend Florida International University, and brought a critical eye to all project discussions. Dr. John Berry provided helpful editorial feedback as well as a compassionate listening ear. Dr. Lee Hearn provided much-needed materials and ideas. Dr. Fenfei Leng provided valuable suggestions regarding method validation. Dr. DeEtta Mills rendered assistance with project planning and time management. I would also like to thank the people outside of Florida International University who provided invaluable assistance and support. Dr. Lisa Lang of the BATFE Laboratory provided me with instrument access, guidance, and friendship. Dr. Mark Miller of the FBI Laboratory granted me a wonderful opportunity to work as a Visiting Scientist. My experiences in that program were excellent. Kelly Mount and Dr. Kirk Yeager of the FBI Laboratory provided many of the post-blast samples for this project, as well as unforgettable moments on the demolition range. v ABSTRACT OF THE DISSERTATION THE DEVELOPMENT OF OPTIZIMED HIGH PERFORMANCE LIQUID CHROMATOGRAPHY SYSTEMS FOR THE ANALYSIS OF IMPROVISED EXPLOSIVES by Megan Nicole Bottegal Florida International University, 2010 Miami, Florida Professor Bruce McCord, Major Professor Existing instrumental techniques must be adaptable to the analysis of novel explosives if science is to keep up with the practices of terrorists and criminals. The focus of this work has been the development of analytical techniques for the analysis of two types of novel explosives: ascorbic acid-based propellants, and improvised mixtures of concentrated hydrogen peroxide/fuel. In recent years, the use of these explosives in improvised explosive devices (IEDs) has increased. It is therefore important to develop methods which permit the identification of the nature of the original explosive from post- blast residues. Ascorbic acid-based propellants are low explosives which employ an ascorbic acid fuel source with a nitrate/perchlorate oxidizer. A method which utilized ion chromatography with indirect photometric detection was optimized for the analysis of intact propellants. Post-burn and post-blast residues if these propellants were analyzed. It was determined that the ascorbic acid fuel and nitrate oxidizer could be detected in intact vi propellants, as well as in the post-burn and post-blast residues. Degradation products of the nitrate and perchlorate oxidizers were also detected. With a quadrupole time-of-flight mass spectrometer (QToFMS), exact mass measurements are possible. When an HPLC instrument is coupled to a QToFMS, the combination of retention time with accurate mass measurements, mass spectral fragmentation information, and isotopic abundance patterns allows for the unequivocal identification of a target analyte. An optimized HPLC-ESI-QToFMS method was applied to the analysis of ascorbic acid-based propellants. Exact mass measurements were collected for the fuel and oxidizer anions, and their degradation products. Ascorbic acid was detected in the intact samples and half of the propellants subjected to open burning; the intact fuel molecule was not detected in any of the post-blast residue. Two methods were optimized for the analysis of trace levels of hydrogen peroxide: HPLC with fluorescence detection (HPLC-FD), and HPLC with electrochemical detection (HPLC-ED). Both techniques were extremely selective for hydrogen peroxide. Both methods were applied to the analysis of post-blast debris from improvised mixtures of concentrated hydrogen peroxide/fuel; hydrogen peroxide was detected on variety of substrates. Hydrogen peroxide was detected in the post-blast residues of the improvised explosives TATP and HMTD. vii TABLE OF CONTENTS CHAPTER PAGE I. INTRODUCTION ...................................................................................................1 Forensic Analysis of Explosives ..............................................................................1 Overview of Explosives ...........................................................................................3 Featured Explosives .................................................................................................6 Research Goals.......................................................................................................10 II. INSTRUMENTAL ANALYSIS OF EXPLOSIVES.............................................12 Introduction ............................................................................................................12 Sample Preparation ................................................................................................12 High Performance Liquid Chromatography ..........................................................14 Detection Systems for HPLC .................................................................................17 Summary ................................................................................................................38 III. EXPERIMENTAL PROCEDURES ......................................................................39 Introduction ............................................................................................................39 Analysis of Ascorbic Acid-Based Propellants by IC-IPD .....................................40 Analysis of Ascorbic Acid-Based Propellants by HPLC-ESI-QToFMS ...............43 Analysis of Hydrogen Peroxide by HPLC-ED and HPLC-FD ..............................48 IV. ANALYSIS OF ASCORBIC ACID-BASED PROPELLANTS BY IC-IPD .......58 Introduction ............................................................................................................58 Development of IC-IPD Method ...........................................................................67 Validation of IC-IPD Method ................................................................................70 Results of Sample Analysis ...................................................................................74 Conclusions ............................................................................................................89 V. ANALYSIS OF ASCORBIC ACID-BASED PROPELLANTS BY HPLC-ESI-QToFMS .............................................................................................90 Introduction ............................................................................................................90 Development of HPLC-ESI-QToFMS Method .....................................................92 Results of Sample Analysis .................................................................................111 Conclusions ..........................................................................................................137 VI. OPTIMIZATION OF HPLC-ED