Ultrathin Iron Oxide Nanowhiskers as Positive Contrast Agents for Magnetic Resonance Imaging

Abstract

In this paper, a highly innovative concept of using ultrathin iron oxide nanowhiskers as a positive (T1) contrast agent for magnetic resonance imaging (MRI) is demonstrated. Iron oxide nanowhiskers with dimensions of approximately 2 nm × 20 nm are synthesized by heating an iron oleate/oleylamine complex under 150 °C. These nanostructures have very high surface‐to‐volume ratios, leading to strong paramagnetic signal, a property suitable for T1 contrast in MRI. The positive contrast enhancement of these nanowhiskers is demonstrated in vitro and in vivo in a rat model. Successful development of this technology has substantial commercial value in biomedical imaging, potentially leading to the advancement of human healthcare technologies.

Synthesis, characterization, and evaluation of PEGylated first-row transition metal ferrite nanoparticles as T2contrast agents for high-field MRI

“…9), we believe further improvements are possible by, e.g., templating directional growth to form morphological variations like octapods, 23 bricks, 24 or whiskers; 25 or subjecting them to controlled aggregation and/or self-assembly, which are known to lead to higher contrasting abilities.…”

A general approach to the synthesis and detailed characterization of magnetic ferrite nanocubes

“…17,18 Recently, it has been reported that non-spherical iron oxide nanoparticles (NPs) could greatly improve their usefulness for biomedical applications. 6,[19][20][21] Of particular importance, iron oxide nanocubes demonstrate extremely high r 2 relaxivity as negative magnetic resonance imaging (MRI) contrast agents 20 and a high value of the specific absorption rate necessary for hyperthermia cancer treatment. 21 Further, doping of other inorganic ions offers a great way to adjust the physical properties of magnetic ferrite nanoparticles and their usefulness in applications.…”

Magnetic nanoparticles: material engineering and emerging applications in lithography and biomedicine

“…Red circle indicates the bleb at the site of injection. Copyright © Royal Chemical Society 2015 [29]. …”

“…Recently, it has been shown that non-spherical iron oxide nanoparticles could improve their usefulness for biomedical applications. For examples, ultrathin iron oxide nanowires can serve as effective T 1 MRI contrast agents [29]. Iron oxide nanoworm-like particles formed by aggregation of spherical nanoparticles showed increased blood circulation time and more effective targeting [30].…”