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Mariawoodcockpdfa.Pdf ABSTRACT EFFICIENCY OF COMMON EXTRACTIONS FOR METHAMPHETAMINE AND PSEUDOEPHEDRINE IN FORENSIC DRUG ANALYSIS In forensic casework, liquid-liquid extractions are the most common technique used for drug evidence analysis and conditions are chosen by the analyst to best fit the type of evidence, instrumental conditions, legal requirements, and analysis criteria. The solvent polarity, type of aqueous modifier, and concentration of modifier used in an extraction scheme impact the solubility and extraction of the analytes. This work evaluated the dependence of extraction efficiency on solvent, modifier, and modifier concentration by using methamphetamine and pseudoephedrine in liquid-liquid extractions. A modified internal standard was used to calculate extraction efficiencies and recoveries were semi-quantitative. They varied between 50% - 90% for methamphetamine and 25% - 95% for pseudoephedrine, provided sufficient modifier was added. Derivatization by acetylation greatly improved the detection of pseudoephedrine. Recoveries of methamphetamine using targeted extraction procedures with hexane and 6.00 M sodium hydroxide or saturated sodium bicarbonate were adequate for qualitative confirmation. The extraction schemes with methylene chloride and chloroform proved best suited for low abundance and trace material analysis due to their increased recoveries. Maria A. Woodcock May 2013 EFFICIENCY OF COMMON EXTRACTIONS FOR METHAMPHETAMINE AND PSEUDOEPHEDRINE IN FORENSIC DRUG ANALYSIS by Maria A. Woodcock A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemistry in the College of Science and Mathematics California State University, Fresno May 2013 APPROVED For the Department of Chemistry: We, the undersigned, certify that the thesis of the following student meets the required standards of scholarship, format, and style of the university and the student's graduate degree program for the awarding of the master's degree. Maria A. Woodcock Thesis Author Eric Person (Chair) Chemistry Melissa Golden Chemistry Mark F. Kalchik California Department of Justice For the University Graduate Committee: Dean, Division of Graduate Studies AUTHORIZATION FOR REPRODUCTION OF MASTER’S THESIS X I grant permission for the reproduction of this thesis in part or in its entirety without further authorization from me, on the condition that the person or agency requesting reproduction absorbs the cost and provides proper acknowledgment of authorship. Permission to reproduce this thesis in part or in its entirety must be obtained from me. Signature of thesis author: ACKNOWLEDGMENTS I thank everyone who contributed to this paper: Jessica Winn for her comments and editor’s eye, Dr. Eric Person for his time and direction, Mark Kalchik and Dr. Melissa Golden for their review and input, and the staff at the BFS Fresno Laboratory. Most of all, I thank my friends and family especially: Trias Murillo who is my guiding force in this and all things, Cassandra Hathaway for her thoughtful advice and friendship, my Auntie Chris who listened with sincere interest, and to Team 8742 and all four legged mascots for your love, without you this paper would not be possible. TABLE OF CONTENTS Page LIST OF TABLES ................................................................................................. vii LIST OF FIGURES ............................................................................................... viii INTRODUCTION AND LITERATURE REVIEW ................................................ 1 Types and Classes of Drugs .............................................................................. 2 Purity and Common Diluents ............................................................................ 4 Homogeneity and Representative Sampling ..................................................... 5 Trends in Drug Submissions ............................................................................. 6 Legal Requirements & Analysis Criteria .......................................................... 7 Forensic Laboratory Analysis ........................................................................... 9 Extraction Efficiency of Liquid-Liquid Extractions ....................................... 19 Methamphetamine Analysis ............................................................................ 26 Methamphetamine Manufacturing .................................................................. 28 Ephedrine and Pseudoephedrine Studies ........................................................ 31 Research Aims ................................................................................................ 34 MATERIALS AND METHODS ........................................................................... 36 Chemicals and Solutions ................................................................................. 36 Instrumental Conditions .................................................................................. 37 Extraction Procedures ..................................................................................... 38 RESULTS AND DISCUSSION ............................................................................ 43 Selection of Internal Standard ......................................................................... 43 Calibration Method Selection ......................................................................... 44 Survey of Extraction Conditions ..................................................................... 49 Extract Derivatizations .................................................................................... 61 vi vi Page Limitations ...................................................................................................... 64 CONCLUSION ...................................................................................................... 67 Recommendations ........................................................................................... 69 REFERENCES ....................................................................................................... 71 APPENDICES ........................................................................................................ 77 APPENDIX A: PSEUDOEPHEDRINE CHROMATOGRAMS .......................... 78 APPENDIX B: BILAYER CALIBRATIONS ....................................................... 80 LIST OF TABLES Page Table 1. SWGDRUG Categories of Analytical Techniques – Frequently Used Techniques are Bold ............................................................................... 10 Table 2. Common Chemical Color Tests .............................................................. 11 Table 3. Common Analytical Organic Solvents .................................................... 21 Table 4. Extraction Scheme Variables .................................................................. 50 Table 5. Methamphetamine Recoveries - 0.25 mg/mL ......................................... 51 Table 6. Ten Most Efficient Extractions for Methamphetamine - 0.25 mg/mL ... 52 Table 7. Methamphetamine Recoveries - 0.50 mg/mL ........................................ 56 Table 8. Pseudoephedrine Recoveries (Without Derivatization) - 0.25 mg/mL ... 58 Table 9. Ten Most Efficient Extractions for Pseudoephedrine - 0.25 mg/mL ...... 59 Table 10. Pseudoephedrine Recoveries (Without Derivatization) - 0.050 mg/mL 60 Table 11. Pseudoephedrine Derivatized Recoveries - 0.25 mg/mL ....................... 63 Table 12. Pseudoephedrine Derivatized Recoveries - 0.050 mg/mL ..................... 63 Table 13. Methamphetamine Derivatized Recoveries - 0.25 mg/mL .................... 63 Table 14. Methamphetamine Derivatized Recoveries - 0.50 mg/mL .................... 63 LIST OF FIGURES Page Figure 1. Fractional Composition of Methamphetamine ...................................... 17 Figure 2. Chemical Structures of Amphetamine-Type Stimulants ....................... 27 Figure 3. Ephedrine and Pseudoephedrine Chemical Structures .......................... 33 Figure 4. Chemical Structures of Methamphetamine and Pseudoephedrine ........ 35 Figure 5. Electron Ionization Mass Spectra for methamphetamine (top), pseudoephedrine (middle) and anthracene (bottom) showing the prominent 58 and 178 m/z fragments used for selective ion monitoring. .............................................................................................. 39 Figure 6. Methamphetamine Calibration Comparison – Multi and Single Point ........................................................................................................ 46 Figure 7. Pseudoephedrine Calibration Comparison ............................................. 48 Figure 8. Derivatized Pseudoephedrine ................................................................. 57 Figure A1. Peak shape comparisons of 0.050 mg/mL pseudoephedrine extracted with 6.00 M NaOH into Ethyl acetate. Top to bottom: Initial injection with internal standard, Derivatized injection with internal standard, Enlargement of pseudoephedrine from initial injection. .................................................................................................. 79 Figure B1. Methamphetamine calibrations using a basified bilayer extraction technique with ethyl acetate as the solvent. ............................................ 81 Figure B2. Methamphetamine calibrations using a basified bilayer extraction technique. Solvents used top to bottom: Hexane, Hexane, Petroleum ether. .......................................................................................................
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