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Magnetic Iron Oxide Nanoparticles: Synthesis, Characteristics, Magnetic Behavior, and Biomedical Applications New Jersey Institute of Technology Digital Commons @ NJIT Theses Electronic Theses and Dissertations Spring 5-31-2012 Magnetic iron oxide nanoparticles: synthesis, characteristics, magnetic behavior, and biomedical applications Chengyin Fu New Jersey Institute of Technology Follow this and additional works at: https://digitalcommons.njit.edu/theses Part of the Materials Science and Engineering Commons Recommended Citation Fu, Chengyin, "Magnetic iron oxide nanoparticles: synthesis, characteristics, magnetic behavior, and biomedical applications" (2012). Theses. 138. https://digitalcommons.njit.edu/theses/138 This Thesis is brought to you for free and open access by the Electronic Theses and Dissertations at Digital Commons @ NJIT. It has been accepted for inclusion in Theses by an authorized administrator of Digital Commons @ NJIT. For more information, please contact [email protected]. Copyright Warning & Restrictions The copyright law of the United States (Title 17, United States Code) governs the making of photocopies or other reproductions of copyrighted material. Under certain conditions specified in the law, libraries and archives are authorized to furnish a photocopy or other reproduction. One of these specified conditions is that the photocopy or reproduction is not to be “used for any purpose other than private study, scholarship, or research.” If a, user makes a request for, or later uses, a photocopy or reproduction for purposes in excess of “fair use” that user may be liable for copyright infringement, This institution reserves the right to refuse to accept a copying order if, in its judgment, fulfillment of the order would involve violation of copyright law. Please Note: The author retains the copyright while the New Jersey Institute of Technology reserves the right to distribute this thesis or dissertation Printing note: If you do not wish to print this page, then select “Pages from: first page # to: last page #” on the print dialog screen The Van Houten library has removed some of the personal information and all signatures from the approval page and biographical sketches of theses and dissertations in order to protect the identity of NJIT graduates and faculty. ABSTRACT MAGNETIC IRON OXIDE NANOPARTICLES: SYNTHESIS, CHARACTERISTICS, MAGNETIC BEHAVIOR, AND BIOMEDICAL APPLICATIONS by Chengyin Fu Magnetic iron oxide nanoparticles are attracting increasing attention due to their interesting properties that can be applied in a great number of applications such as catalysis and biomedicine. This thesis focuses on the synthesis, characteristics, and biomedical applications of iron oxide nanoparticles. The two most common iron oxides, including magnetite and maghemite, are discussed in this thesis. For most of their applications, the magnetic behavior of iron oxide nanoparticles in a fluid is very important, especially, the high gradient magnetic separation of the particles from a nonmagnetic liquid medium, such as blood in the human body. A 2D model, which represents a slice through the center of a spherical particle in a fluid, is created in this thesis, and only the magnetic force and the drag force are taken into consideration. The magnetization of the particle is calculated by using the Langevin function, and the fluid drag force is calculated by using the Navier–Stokes equation. The trajectory function for this model is calculated, and the trajectories are drawn for specific cases. MAGNETIC IRON OXIDE NANOPARTICLES: SYNTHESIS, CHARACTERISTICS, MAGNETIC BEHAVIOR, AND BIOMEDICAL APPLICATIONS by Chengyin Fu A Thesis Submitted to the Faculty of New Jersey Institute of Technology in Partial Fulfillment of the Requirements for the Degree of Master of Science in Materials Science and Engineering Interdisciplinary Program in Materials Science and Engineering May 2012 APPROVAL PAGE MAGNETIC IRON OXIDE NANOPARTICLES: SYNTHESIS, CHARACTERISTICS, MAGNETIC BEHAVIOR, AND BIOMEDICAL APPLICATIONS Chengyin Fu Dr. N.M. Ravindra, Thesis Advisor Date Professor of Physics, NJIT Dr. Ken Ahn, Committee Member Date Assistant Professor of Physics, NJIT Dr. Michael Jaffe, Committee Member Date Research Professor of Biomedical Engineering, NJIT BIOGRAPHICAL SKETCH Author: Chengyin Fu Degree: Master of Science Date: May 2012 Undergraduate and Graduate Education: • Master of Science in Materials Science and Engineering, New Jersey Institute of Technology, Newark, NJ, 2012 • Bachelor of Science in Materials Science and Engineering, Tongji University, Shanghai, P. R. China, 2008 Major: Materials Science and Engineering iv To people that I love. To people that love me. You make my life wonderful. v ACKNOWLEDGMENT I would like to express the deepest appreciation to my thesis advisor, Dr. N.M. Ravindra. Without his guidance and persistent help this thesis would not have been possible. I would like to thank Dr. Ken Ahn and Dr. Michael Jaffe for being part of my thesis review committee and for providing suggestions and guidance for my research. I would like to thank Dr. N.M Ravindra for his valuable suggestion and great help in my study in NJIT. Finally, I would like to thank my parents, who have been supportive to me during my life. Thank you for their greatest love. vi TABLE OF CONTENTS Chapter Page 1 INTRODUCTION……............................………………..…………………………. 1 2 BASIC MAGNETIC PROPERTIES OF IRON OXIDE NANOPARTICLES…….. 3 3 SYNTHESIS OF PARTICLES …………………………………………………….. 8 3.1 Coprecipitation………………………………...……………………………….. 9 3.2 Hydrothermal Metheds……………………………………………………......... 15 3.3 High-temperature Decomposition of Organic Precursors……………………… 16 3.4 Sol-Gel Methods……………………………………………………………….. 18 3.5 Miroemulsions………………………………………………………………….. 19 3.6 Polyol Methods………………………………………………………………… 21 3.7 Electrochemical Methods………………………………………………………. 22 3.8 Aerosol/Vapor Method…………………………………………………………. 22 3.9 Sonolysis……………………………………………………………………….. 23 4 CHARACTERISTICS OF PARTICLES…………………………….……………... 25 4.1 Stability of Colloids……………………………………………………………. 25 4.2 Characterization of Particles…….………………………………………….….. 29 4.3 Magnetic Properties of Colloids……………………………………………… 30 5 BIOMEDICAL APPLICATIONS………………………………………………….. 36 6 MAGNETIC IRON OXIDE NANOPARTICLES IN FLUIDS………………….... 40 6.1 Model…………………………………………………………………………... 40 6.2 The Forces and Trajectory……………………………………………………... 41 vii TABLE OF CONTENTS (Continued) Chapter Page 6.3 Results……..…………….……………………………………………………... 45 7 CONCLUSIONS……………………………………………………………………. 47 REFERENCES ………………………………………………………………………... 48 viii LIST OF TABLES Table Page 1.1 Physical Properties of Iron Oxides…………………...…....………………..…… 1 3.1 Comparison of Different Characteristics of the Iron Oxide Nanoparticles Produced by Different Fabrication Methods……………………………………... 24 4.1 Coating Materials of Iron Oxide Nanoparticles and Their Applications ………... 27 6.1 The Values Used in the Simulation...……..………………………….………….. 45 ix LIST OF FIGURES Figure Page 1.1 Crystal structure of magnetite and maghemite………..…………………………. 2 2.1 The magnetic spin alignments in different types of crystals………….………….. 4 2.2 Magnetic domains in a crystal.…..………...…………………………………….. 5 2.3 The Hysteresis loop...……..……………………………………………………… 6 3.1 A comparison of published work on the synthesis of magnetic nanoparticles by three different routes…..…………………………………………………………. 9 3.2 The LaMer Diagram …………………………………………………………….. 11 3.3 TEM micrographs of magnetite nanoparticles…………………………….……... 13 3.4 The structure of an aqueous core with aerosol-OT/n-hexane reverse micelles….. 20 3.5 The microemulsion method producing highly monodispersed iron oxide nanoparticles……………………………………………………………………... 20 3.6 Transmission electron microscopy pictures of magnetic particles prepared in (a) bulk solutions and (b) in w/o microemulsions………………...….……………… 21 4.1 Changing of the magnetic energy with the angle between the magnetization vector and the easy axis………………………………………………………….. 31 4.2 Illustration of the Néel relaxation and the Brownian relaxation in a colloid…….. 34 5.1 Recent biomedical applications of magnetic iron oxide nanoparticles…………... 37 6.1 Schematic diagram of the model…………………………………………………. 41 6.2 The trajectories of the particle starting at height 10, 25, and 50 µm, and the x and y axes have the unit of µm…………………………………………………... 46 x CHAPTER 1 INTRODUCTION Nanoscience is the study of matters whose size is on the nanometer scale. Comparing to the bulk materials, the materials on nanoscale have many unusual properties such as electrical, optical, and magnetic properties. Iron oxide nanoparticles are iron oxide particles with diameters between 1 and 100 nanometers. They have attracted much attention due to their fine magnetic properties and massive fields of applications in modern science. The most common iron oxides in nature and biomedical applications are magnetite (Fe304) and maghemite (γ-Fe2O3), so they are also the subject of this thesis. The physical propertied of them are listed in Table 1.1. Table 1.1 Physical Properties of Iron Oxides [1] Properties Magnetite (Fe3O4) Maghemite (γ-Fe2O3) Density (g/cm3) 5.18 4.87 Melting point (°C) 1583-1597 - Hardness 5.5 5 Type of magnetism Ferromagnetic Ferromagnetic Curie temperature (K) 850 820-986 2 Ms at 300K (A-m /kg) 92-100 60-80 Standard free energy of -1012.6 -711.1 formation ΔGf° (kJ/mol) Crystallographic system Cubic Cubic or tetrahedral Structural type Inverse spinel Defect spinel Space group Fd3m P4332 (cubic); P41212 (tetragonal) Lattice parameter (nm) a = 0.8396 a = 0.83474 (cubic); a = 0.8347, c = 2.501 (tetragonal) 1 2 Magnetite
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