OPTIMIZING IRON OXIDE NANOPARTICLES FOR MAGNETIC IMAGING AND ANTIBACTERIAL APPLICATIONS by SHU FEN SITU Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Dissertation Adviser: Prof. Anna Cristina S. Samia Department of Chemistry CASE WESTERN RESERVE UNIVERSITY May, 2016 i CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of SHU FEN SITU candidate for the degree of Doctor of Philosophy*. Committee Chair Prof. Alfred B. Anderson (Committee Chair, Department of Chemistry, CWRU) Committee Member Prof. Clemens Burda (Department of Chemistry, CWRU) Committee Member Prof. Michael G. Zagorski (Department of Chemistry, CWRU) Committee Member Prof. Anna Cristina S. Samia (Department of Chemistry, CWRU) Committee Member Prof. Mark A. Griswold (Department of Radiology, CWRU) Date of Defense March 24, 2016 *We also certify that written approval has been obtained for any proprietary material contained therein ii To my loving parents, Yim and Hua, my brother, Tim, my mother- and father-in-law, Jody and Paul, and my husband, Scott Acknowledgements First, I am expressing my deepest appreciation of my advisor, Prof. Anna Cristina S. Samia, for always providing endless guidance and support for my academic and professional pursuits, and continuously pushing me forward outside of my comfort zone. I am very fortunate to have such a wonderful mentor and caring friend. Thank you also to my committee members, Prof. Alfred B. Anderson, Prof. Clemens Burda, Prof. Michael G. Zagorski and Prof. Mark A. Griswold, who have stimulated thought and created a community supportive of inquiry. I express my sincere gratitude to all of the collaborators who created the dialectic necessary for scientific progress. Thank you to Dr. Lisa Bauer and Prof. Mark A. Griswold for your expertise in magnetic particle relaxometry and magnetic particle imaging. Working with you is both productive and exciting. I appreciate Jingshan Cao and Prof. João Maia for collaborating on reactive extrusion and polymer characterization. Thank you also to Prof. LaShanda Korley for providing instrumentations and assistance with mechanical testing and thermal analysis. I am grateful to have access to TEM instruments at the University Hospital, Case Center of Structural Biology and Cleveland Clinic Foundation. I am very appreciative to have the assistance from Midori Hitomi on TEM throughout my years here as a graduate student. I am grateful to have all of the past and present Samia group members (Chuhang Chen, Eric Abenojar, Monica Navarreto Lugo, Sameera Wickramasinghe, Adam Vianna, Aria Bredt, Angela Crise, Jimmy Lee, Shuang Qin, Jon Flikkema, Dr. Michele Pablico Lansigan, and many more) working by my side throughout graduate school. I am especially grateful to have the help and friendship from Dr. Adriana Popa; our passion and enthusiasm for science brought us together, iii and has created a long lasting friendship. Thank you to members of the Burda research group (Anton Kovalsky, Chris McCleese, Charles Kolodziej, Dr. Gustavo Parra, Dr. Xin Guo and Wei- Chun Lin) for their supports. Many thanks to my loving family and close friends for their unconditional love and supports. Without their guidance, patience, understanding, encouragement, and laughter, the completion of this work would have never been possible. iv Table of Contents Acknowledgements .............................................................................................................. i Table of Contents ............................................................................................................... iii List of Tables ................................................................................................................... viii List of Figures .................................................................................................................... ix List of Schemes .............................................................................................................. xxiii List of Symbols and Abbreviations................................................................................. xxv Abstract ........................................................................................................................... xxx Chapter 1. Introduction to Nanomaterials 1.1 General Introduction ................................................................................................. 1 1.2 Fundamentals of Nanomagnetism............................................................................. 2 1.2.1 Magnetic Nanomaterials .................................................................................... 2 1.2.2 Superparamagnetism .......................................................................................... 7 1.2.3 Iron Oxide Spinel Ferrites .................................................................................. 9 1.3 Synthetic Methods .................................................................................................... 9 1.4 Magnetic Polymer Nanocomposites ....................................................................... 12 1.4.1 General Types of Magnetic Polymer Nanocomposites ................................... 13 1.4.2 Processing Methods for Magnetic Polymer Nanocomposites ......................... 15 1.5 Nanoparticle and Nanocomposites Characterization Methods ............................... 17 1.5.1 Microscopy Methods ....................................................................................... 17 1.5.2. Spectroscopy Methods .................................................................................... 19 1.5.3 Thermal Analysis ............................................................................................. 20 v 1.5.4. Powder X-ray Diffraction ............................................................................... 21 1.5.5. Dynamic Light Scattering ............................................................................... 23 1.5.6 Superconducting Quantum Interference Device Magnetometry ..................... 23 1.5.7 Mechanical Testing .......................................................................................... 24 1.5.8 Rheological Characterization ........................................................................... 26 1.6 Applications of Iron Oxide Nanoparticles .............................................................. 27 1.6.1 Magnetic Resonance Imaging .......................................................................... 27 1.6.2 Magnetic Particle Imaging ............................................................................... 29 1.6.3 Magnetic Hyperthermia ................................................................................... 40 1.7 References ............................................................................................................... 42 Chapter 2. Synthesis of Anisotropic Iron Oxide Concave Nanocubes as T2 MRI Contrast Agents 2.1 Introduction ............................................................................................................. 50 2.2 Solvent Effect on Iron Oxide Nanoparticle Morphology ....................................... 52 2.3 Magnetic Characterization of Iron Oxide Nanoparticles ........................................ 57 2.4 Magnetic Relaxation Measurements of Iron Oxide Nanoparticles ......................... 59 2.5 Time Evolution of the Concave Nanocubes Growth .............................................. 62 2.6 Effects of NaCl on Nanoparticle Morphology ........................................................ 63 2.7 Coordinating Capping Ligand Effect on Nanoparticle Morphology ...................... 65 2.8 Conclusions ............................................................................................................. 68 2.9 References ............................................................................................................... 68 Chapter 3. Optimizing Iron Oxide Nanoparticle Tracers for Magnetic Particle Imaging – Guided Hyperthermia (hMPI) vi 3.1 Introduction ............................................................................................................. 71 3.2 Magnetic Nanoparticle Synthesis and Characterization ......................................... 74 3.2.1 Synthesis of Magnetite Spherical Nanoparticles ............................................. 74 3.2.2 Synthesis of Magnetite Cubic Nanoparticles ................................................... 75 3.2.3 Synthesis of Zinc Doped Magnetite Spherical Nanoparticles ......................... 76 3.2.4 Synthesis of Zinc Doped Magnetite Cubic Nanoparticles ............................... 76 3.2.5 Structural and Magnetic Properties .................................................................. 76 3.3 Iron Oxide Nanocomposite Fabrication .................................................................. 80 3.4 Magnetic Particle Relaxometer Design .................................................................. 81 3.5 Magnetic Particle Relaxometry Measurements ...................................................... 84 3.6 Zinc-Dopant Effect on the Magnetic Particle Imaging Signal of IONPs ............... 84 3.7 Shape Effect on the MPI Signal of IONPs.............................................................. 86 3.8 Magnetic Hyperthermia Measurements .................................................................. 88 3.9 Magnetic Particle Imaging and Magnetic Hyperthermia Performance .................. 90 3.10 Immobilization Effect on the MPI Signal and Hyperthermia Performance ......... 93 3.11 Magnetic Hyperthermia Measurements under a Static Magnetic Field ................ 95 3.12 Magnetic Hyperthermia Measurements under a Gradient Magnetic Field ........... 98 3.13 Conclusions ......................................................................................................... 103 3.14 References ........................................................................................................... 103 Chapter 4. Study and Control of the Magnetic and Mechanical Properties of Magnetite – Polyethylene Nanocomposites for Biofilm Inactivation 4.1 Introduction ........................................................................................................... 107 vii 4.2 Synthesis and Functionalization of the Magnetite Nanoparticles ......................... 111 4.3 Fabrication of the Magnetite – Polyethylene Nanocomposites ............................ 115 4.3.1 Reactive Extrusion of the Magnetite-Polyethylene Nanocomposites ............ 115 4.3.2 Effects of Reactive Extrusion on Polyethylene Oxidation ............................ 119 4.3.3 Mechanical Properties of the Magnetite – Polyethylene Nanocomposites .... 120 4.3.4 Rheological Properties of the Magnetite – Polyethylene Nanocomposites ... 123 4.3.5 Thermal Properties of the Magnetite – Polyethylene Nanocomposites ......... 125 4.3.6 Investigation of the Azide Coupling .............................................................. 128 4.4 Magnetic Hyperthermia Properties of Nanocomposites ....................................... 130 4.4.1 Magnetic Hyperthermia Performance ............................................................ 130 4.4.2 Application in Biofilm Eradication ................................................................ 134 4.4.3 Effect of Magnetic Hyperthermia Treatment on the Mechanical Properties. 139 4.5 Conclusions ........................................................................................................... 140 4.6 References ............................................................................................................. 141 Chapter 5. Hybrid Iron Oxide@Carbon Nanochains for Antibacterial Applications 5.1 Introduction ........................................................................................................... 146 5.2 Synthesis of Iron Oxide Nanoparticles ................................................................. 148 5.3 Iron Oxide@Carbon Nanochain synthesis ............................................................ 149 5.4 Materials Characterization .................................................................................... 149 5.5 Formation of Iron Oxide@Carbon Nanochains .................................................... 150 5.6 Cell Viability Assays by Colony Counting Method ............................................. 165 5.7 Superoxide Anion Detection by XTT Assay ........................................................ 175 viii 5.8 Antibacterial Recyclability Studies....................................................................... 179 5.10 Conclusions ......................................................................................................... 183 5.11 References ........................................................................................................... 184 Chapter 6. Research Outlook ...................................................................................................... 191 6.1 References ............................................................................................................. 192 ix List of Tables Table 2.2.1. List of reagents and reflux temperatures used during the iron oxide nanoparticle synthesis. ............................................................................................................... 54 Table 2.3.1. The summary of particle diameter, saturation magnetization (M ), and transverse s relaxivity (r ) values for the IONPs synthesized using different solvent volume 2 ratios (all 1-octadecene (ODE), 1:1 ODE:trioctylamine (TOA), 1:2 ODE:TOA, 1:3 ODE:TOA, 1:4 ODE:TOA, and all TOA). ........................................................... 59 Table 2.6.1. Elemental analysis of NaCl salt crystal, iron oleate precursor with 1x and 8x wash steps obtained using energy dispersive x-ray spectroscopy (EDS). Results are shown as concentration percentages. .................................................................... 65 Table 2.7.1. The summary of reagent amount, particle diameter, and IONP morphology from the IONPs synthesized using 100 % TOA and different amounts of oleic acid. ........ 67 Table 3.2.5.1. Summary of the IONP structural and magnetic properties as well as key results from relaxometry and magnetic hyperthermia measurements. ............................. 80 Table 3.10.1. Summary of magnetic relaxometry and hyperthermia measurements of iron oxide nanocomposites. .................................................................................................... 95 Table 4.2.1. The summary of the estimated ligand coverage on the vinyl- and azide- functionalized magnetite nanoparticles. .............................................................. 116 Table 5.5.1. Iron oxide structural composition (in wt %) estimated using Rietveld analysis. . 158 x