Carbon-coated FeCo nanoparticles as sensitive magnetic-particle-imaging tracers with photothermal and magnetothermal properties

Abstract

The low magnetic saturation of iron oxide nanoparticles, developed primarily as contrast agents for magnetic resonance imaging, limits the sensitivity of their detection via magnetic particle imaging. Here, we show that FeCo nanoparticles 10 nm in core diameter bearing a graphitic carbon shell decorated with poly(ethylene glycol) provide a signal intensity for magnetic particle imaging that is about 6-fold and 15-fold higher than the signals from the superparamagnetic iron oxide tracers Vivotrax and Feraheme at the same molar concentration of iron. We also show that the nanoparticles have photothermal and magnetothermal properties and can thus be used for tumour ablation in mice, and that they have high optical absorbance in a broad near-infrared region spectral range (700–1200 nm in wavelength), which also makes them suitable as tracers for photoacoustic imaging. As sensitive multifunctional and multimodal imaging tracers, carbon-coated FeCo nanoparticles may confer advantages in cancer imaging and hyperthermia therapy.

Recent Advances of Bioresponsive Nano-Sized Contrast Agents for Ultra-High-Field Magnetic Resonance Imaging

“…Figures 6C,D shows the individual MRI image and SPECT image after injecting each specific contrast agent. When MRI and SPECT are integrated for diagnosis, the combined image of dual-modality is shown in Figure 6E, which paves the way for further investigation of cells and gene patterns in gene expression with the multimodal molecular imaging technique (Jung et al, 2020;Song et al, 2020).…”

Materdicine: Interdiscipline of materials and medicine

“…To compete efficiently against small‐molecule CAs, nanomaterials must cause negligible biosafety risk after in vivo administration, while furnishing at least one substantial superiority, such as improved resolution, augmented imaging sensitivity, or multiplexing capability 30 . Currently, the representative nanomaterial‐based imaging modalities in clinical settings or preclinical research include MRI, 31 positron emission tomography (PET), 32 single‐photon emission computed tomography, 33 computed tomography (CT), 34 optical fluorescence imaging, 35 PA imaging, 36 and ultrasound (US) imaging 37 …”

Magnetocrystalline and Surface Anisotropy in CoFe2O4 Nanoparticles

“…Within the last few years, magnetic nanoparticles have contributed to the development of a variety of cutting edge technologies in fields such as ferrofluids [ 1 ], microwave devices [ 2 ], biomedicine [ 3 , 4 ], or catalysis [ 5 , 6 ]. The growing interest that magnetic nanoparticles attract demands a fundamental understanding of their properties, which are very different from their bulk counterparts.…”