Ultrasmall Fe3O4@Au Composite Nanoparticles with Different Sizes of Fe3O4 for Magnetic Hyperthermia

• Published in: IEEE transactions on magnetics 2023-11, Vol.59 (11), p.1-1
• Main Authors: Tonthat, Loi, Ogawa, Tomoyuki, Yabukami, Shin
• Format: Article
• Language: English
• Subjects: Coatings; Core/shell; Electron microscopes; Fe<sub xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">3 O<sub xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">4 @Au; Gold; Heating; Hyperthermia; Iron; Iron oxides; Magnetic fields; magnetic hyperthermia; Magnetic properties; Magnetic resonance imaging; Magnetism; Magnetization; magneto-plasmonic nanoparticles; Nanoparticles; Specific absorption rate; theranostic agent; Thermal decomposition; Transmission electron microscopy
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2023.3287505

We present the synthesis and characterization of ultrasmall iron oxide/gold composite nanoparticles (Fe 3 O 4 @Au NPs) with different Fe 3 O 4 sizes, along with an evaluation of their heating efficiency for potential use in magnetic hyperthermia applications. The Fe 3 O 4 NPs of approximately 5 nm, 10 nm, and 13 nm were synthesized using the thermal decomposition method, followed by gold deposition via the reduction of gold acetate at 190°C. The morphology, structure, and magnetic properties of as-prepared Fe 3 O 4 and their Fe 3 O 4 @Au NPs were determined and characterized by TEM, EDX, XRD, and VSM analyses. The magnetization of Fe 3 O 4 NPs increased with increasing their size, reaching 74.7 emu/g for ~13 nm NPs. The Fe 3 O 4 @Au NPs contained 94.3%, 96.3%, 77.0% Au (wt%) for Fe 3 O 4 ~5 nm@Au, Fe 3 O 4 ~10 nm@Au, Fe 3 O 4 ~13 nm@Au, respectively, estimated from the magnetization values. The heating efficiency (specific absorption rate, SAR) demonstrated an increasing trend with Fe 3 O 4 size, reaching maximum values of 136.7 and 23.4 W/g under a magnetic field of 25.7 kA/m and 267 kHz for Fe 3 O 4 ~13 nm, Fe 3 O 4 ~13 nm@Au NPs, respectively. These results indicate high heating efficient capabilities and the potential use of NPs for magnetic hyperthermia applications.