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Development of Advanced Capillary Electrophoresis Techniques With Florida International University FIU Digital Commons FIU Electronic Theses and Dissertations University Graduate School 7-1-2014 Development of Advanced Capillary Electrophoresis Techniques with UV and Mass Spectrometry Detection for Forensic, Pharmaceutical and Environmental Applications Hanzhuo Fu Florida International University, [email protected] DOI: 10.25148/etd.FI14071160 Follow this and additional works at: https://digitalcommons.fiu.edu/etd Recommended Citation Fu, Hanzhuo, "Development of Advanced Capillary Electrophoresis Techniques with UV and Mass Spectrometry Detection for Forensic, Pharmaceutical and Environmental Applications" (2014). FIU Electronic Theses and Dissertations. 1531. https://digitalcommons.fiu.edu/etd/1531 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 DEVELOPMENT OF ADVANCED CAPILLARY ELECTROPHORESIS TECHNIQUES WITH UV AND MASS SPECTROMETRY DETECTION FOR FORENSIC, PHARMACEUTICAL AND ENVIRONMENTAL APPLICATIONS A dissertation submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY in CHEMISTRY by Hanzhuo Fu 2014 To: Interim Dean Michael R. Heithaus College of Arts and Sciences This dissertation, written by Hanzhuo Fu, and entitled Development of Advanced Capillary Electrophoresis Techniques with UV and Mass Spectrometry Detection for Forensic, Pharmaceutical and Environmental Applications, 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. _______________________________________ Yong Cai _______________________________________ David Chatfield _______________________________________ Chenzhong Li _______________________________________ J. Martin E. Quirke _______________________________________ Bruce R. McCord, Major Professor Date of Defense: July 1, 2014 The dissertation of Hanzhuo Fu is approved. _______________________________________ Interim Dean Michael R. Heithaus College of Arts and Sciences _______________________________________ Dean Lakshmi N. Reddi University Graduate School Florida International University, 2014 ii © Copyright 2014 by Hanzhuo Fu © Copyright 2014 John Wiley and Sons, Ltd. Merola, G.#, Fu, H.# ( # co-first authors), Tagliaro, F., Macchia, T., and McCord, B. R., Chiral separation of 12 cathinone analogs by cyclodextrin-assisted capillary electrophoresis with UV and mass spectrometry detection. Electrophoresis, 2014. DOI 10.1002/elps.201400077. All rights reserved. iii DEDICATION To my wife Cen, and my parents. I couldn’t have done this without you. May the world stay at peace. 献给 我的妻子，和我的父母。没有你们，我无法做到这一切。 愿世界和平。 iv ACKNOWLEDGMENTS First and foremost, I would like to thank my advisor, Dr. Bruce R. McCord, for providing me the opportunity to be a part of his research group and for his help, support and encouragement. I would never achieve my academics goals without his patience and faith in me. I will always be grateful for his mentorship. I would extend my thanks to my dissertation committee members, Dr. Yong Cai, Dr. David Chatfield, Dr. Chenzhong Li, and Dr. J. Martin E. Quirke, for their advice given to the project and to my Ph.D. study. Special thanks for Dr. Quirke for his assistance on the organic part of this work. I want to thank Jennifer Thomas, Inge Corbin, and Chloe De Perre for their tutorial and assistance on the monolith project, Gustavo Merola for his collaboration on the chiral separation project, and Bingxue Zheng for her cooperation on the microcystin analysis project. I would also like to thank all the previous and current members of Dr. McCord’s research group. I gratefully acknowledge the faculty and staff in the Department of Chemistry & Biochemistry at FIU. Special thanks to Dr. Alexander Mebel and Dr. Xiaotang Wang. Also, I would like to thank my wife for her encouragement and support during my PhD study at FIU, and my family and friends in China, who gave me love, support, and power. Graduate teaching assistant was supported by University Graduate School and Department of Chemistry. Conference travel funding was provided by College of Arts & Sciences and Graduate and Professional Student Committee (GPSC). I truly thank all of you from the bottom of my heart. I guess I could plan a trip to Paris?! v ABSTRACT OF THE DISSERTATION DEVELOPMENT OF ADVANCED CAPILLARY ELECTROPHORESIS TECHNIQUES WITH UV AND MASS SPECTROMETRY DETECTION FOR FORENSIC, PHARMACEUTICAL AND ENVIRONMENTAL APPLICATIONS by Hanzhuo Fu Florida International University, 2014 Miami, Florida Professor Bruce R. McCord, Major Professor Capillary electrophoresis (CE) is a modern analytical technique, which is electrokinetic separation generated by high voltage and taken place inside the small capillaries. In this dissertation, several advanced capillary electrophoresis methods are presented using different approaches of CE and UV and mass spectrometry are utilized as the detection methods. Capillary electrochromatography (CEC), as one of the CE modes, is a recent developed technique which is a hybrid of capillary electrophoresis and high performance liquid chromatography (HPLC). Capillary electrochromatography exhibits advantages of both techniques. In Chapter 2, monolithic capillary column are fabricated using in situ photoinitiation polymerization method. The column was then applied for the separation of six antidepressant compounds. Meanwhile, a simple chiral separation method is developed and presented in Chapter 3. Beta cycodextrin was utilized to achieve the goal of chiral separation. Not only twelve cathinone analytes were separated, but also isomers of several analytes were vi enantiomerically separated. To better understand the molecular information on the analytes, the TOF-MS system was coupled with the CE. A sheath liquid and a partial filling technique (PFT) were employed to reduce the contamination of MS ionization source. Accurate molecular information was obtained. It is necessary to propose, develop, and optimize new techniques that are suitable for trace-level analysis of samples in forensic, pharmaceutical, and environmental applications. Capillary electrophoresis (CE) was selected for this task, as it requires lower amounts of samples, it simplifies sample preparation, and it has the flexibility to perform separations of neutral and charged molecules as well as enantiomers. Overall, the present work demonstrates the versatility of capillary electrophoresis methods in forensic, pharmaceutical, and environmental applications. vii TABLE OF CONTENTS CHAPTER PAGE CHAPTER 1 GENERAL INTRODUCTION .....................................................................1 1.1 Historical Background ...................................................................................................1 1.2 Principles of Separation in Capillary Electrophoresis ...................................................3 1.3 Significance of the Work .............................................................................................10 CHAPTER 2 MONOLITHIC CAPILLARY ELECTROCHROMATOGRAPHY FOR THE TRICYCLIC ANTIDEPRESSANTS ........................................................................13 2.1 Introduction ..................................................................................................................13 2.1.1 Introduction of the project .......................................................................................13 2.1.2 Background and significance of capillary electrophoresis and capillary electrochromatography ......................................................................................................15 2.2 Experimental ................................................................................................................20 2.2.1 Chemicals and materials ...........................................................................................20 2.2.2 Instrumentation .........................................................................................................22 2.2.3 Monolithic capillary preparation ...............................................................................23 2.2.4 Sample preparation ...................................................................................................25 2.2.5 Liquid-liquid extraction ............................................................................................26 2.3 Results and Discussion ................................................................................................26 2.3.1 Monolithic columns ..................................................................................................26 2.3.2 Method development and CEC-UV results ..............................................................28 2.3.3 Liquid-liquid extraction and spiked urine sample ....................................................34 2.4 Concluding Remarks ....................................................................................................37 CHAPTER 3 CHIRAL SEPARATION OF CATHINONE ANALOGS BY CYCLODEXTRIN-ASSISTED CAPILLARY ELECTROPHORESIS ...........................38 3.1 Introduction ..................................................................................................................38 3.2 Experimental
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