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Electrification Ionization: Fundamentals and Applications

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Electrification Ionization: Fundamentals and Applications Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 11-12-2019 Electrification Ionization: undamentalsF and Applications Bijay Kumar Banstola Louisiana State University and Agricultural and Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Analytical Chemistry Commons Recommended Citation Banstola, Bijay Kumar, "Electrification Ionization: undamentalsF and Applications" (2019). LSU Doctoral Dissertations. 5103. https://digitalcommons.lsu.edu/gradschool_dissertations/5103 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. ELECTRIFICATION IONIZATION: FUNDAMENTALS AND APPLICATIONS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Chemistry by Bijay Kumar Banstola B. Sc., Northwestern State University of Louisiana, 2011 December 2019 This dissertation is dedicated to my parents: Tikaram and Shova Banstola my wife: Laxmi Kandel ii ACKNOWLEDGEMENTS I thank my advisor Professor Kermit K. Murray, for his continuous support and guidance throughout my Ph.D. program. Without his unwavering guidance and continuous help and encouragement, I could not have completed this program. I am also thankful to my committee members, Professor Isiah M. Warner, Professor Kenneth Lopata, and Professor Shengli Chen. I thank Dr. Fabrizio Donnarumma for his assistance and valuable insights to overcome the hurdles throughout my program. I appreciate Miss Connie David and Dr. Jeonghoon Lee for their support and instructions while working in Mass Spectrometry Facility (MSF). Special thanks to all my colleagues, Kelin Wang, Fan Cao, Chao Dong, Carson W. Szot, Remi Lawal, Achala P. Deenamulla Kankanamalage, Jamira Stephenson and Kelsey Hines for their help, and wonderful moments shared. Finally, I thank my wife and my family for supporting me through every step of my life. iii TABLE OF CONTENTS ACKNOWLEDGEMENTS ........................................................................................................... iii LIST OF TABLES ......................................................................................................................... vi LIST OF FIGURES ...................................................................................................................... vii LIST OF ABBREVIATIONS AND SYMBOLS ........................................................................... x ABSTRACT .................................................................................................................................. xii CHAPTER 1. INTRODUCTION ................................................................................................... 1 1.1 Mass spectrometry .............................................................................................................................. 2 1.2 Ionization in mass spectrometry ......................................................................................................... 4 1.3 Imaging mass spectrometry .............................................................................................................. 13 1.4 Research objectives ........................................................................................................................... 14 CHAPTER 2. A NANOPARTICLE CO-MATRIX FOR MULTIPLY CHARGING IN MATRIX-ASSISTED LASER DESORPTION IONIZATION IMAGING OF TISSUE ........... 16 2.1 Introduction ....................................................................................................................................... 16 2.2 Experimental ..................................................................................................................................... 18 2.3 Results and discussion ...................................................................................................................... 21 2.4 Summary ........................................................................................................................................... 30 CHAPTER 3. PULSED VALVE MATRIX-ASSISTED IONIZATION..................................... 33 3.1 Introduction ....................................................................................................................................... 33 3.2 Experimental ..................................................................................................................................... 35 3.3 Results and discussion ...................................................................................................................... 37 3.4 Summary ........................................................................................................................................... 44 CHAPTER 4. PIEZOELECTRIC MATRIX-ASSISTED IONIZATION .................................... 45 4.1 Introduction ....................................................................................................................................... 45 4.2 Experimental ..................................................................................................................................... 46 4.3 Results and discussion ...................................................................................................................... 50 4.4 Summary ........................................................................................................................................... 58 iv CHAPTER 5. SUBLIMATION ELECTRIFICATION OF ORGANIC COMPOUNDS ............ 59 5.1 Introduction ....................................................................................................................................... 59 5.2 Experimental ..................................................................................................................................... 62 5.3 Results and discussion ...................................................................................................................... 65 5.4 Summary ........................................................................................................................................... 74 CHAPTER 6. CONCLUSIONS AND FUTURE DIRECTIONS ................................................ 75 APPENDIX A. CHEMICALS AND MATERIALS .................................................................... 78 APPENDIX B. LETTERS OF PERMISSION ............................................................................. 80 REFERENCES ............................................................................................................................. 89 VITA ........................................................................................................................................... 107 v LIST OF TABLES Table 2.1. List of multiply charged peaks (m/z) from mouse brain with their intensity and charge obtained with a) 2-NPG, and b) 2-NPG/NP ................................................ 28 Table 5.1. List of compounds with current and charge produced from sublimation with time required for each to reach maximum signal and to decay to 5% of the maximum ...... 70 vi LIST OF FIGURES Figure 1.1. Schematic of ESI .......................................................................................................... 8 Figure 1.2. Schematic of MALDI ................................................................................................. 10 Figure 1.3. Schematic of MAI ...................................................................................................... 12 Figure 2.1. Application of matrix to tissue ................................................................................... 20 Figure 2.2. Mass spectra of 100 pmol cytochrome C on a MALDI target with matrix compounds: A) SA, B) SA/NP, C) 2‐NPG, and D) 2‐NPG/NP ........................................ 22 Figure 2.3. Mass spectra of insulin with a) SA, b) SA/NP, c) 2-NPG, and d) 2-NPG/NP, and myoglobin with e) SA, f) SA/NP, g) 2-NPG, and h) 2-NPG/NP. .................. 23 Figure 2.4. MALDI mass spectra of mouse brain tissue obtained with a) SA, b) SA/NP, c) 2‐NPG, and d) 2‐NPG/NP ....................................................................................... 24 Figure 2.5. Mass spectra obtained from mouse brain tissue with 2-NPG/NP with diameters a) 20 nm, b) 70 nm, c) 400 nm, and d) 1000 nm. ......................................................... 26 Figure 2.6. Fraction of peaks representing the indicated charge state obtained from MALDI mass spectra of mouse brain tissue with A, 2NPG (71 peaks) and B, 2‐NPG/NP matrix (96 peaks) ............................................................................................ 27 Figure 2.7. Images of consecutive mouse brain tissue sections obtained from 8565 m/z and its multiply charged ions with A, 2‐NPG and B, 2‐NPG/NP matrix ...................... 29 Figure 2.8. Images of consecutive mouse brain tissue sections formed by 7573 m/z and multiply charged ions with a) 2-NPG, and b) 2-NPG/NP ...................................................... 31 Figure 3.1. Pulsed valve ...............................................................................................................
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