Structure and dysprosium dopant engineering of gadolinium oxide nanoparticles for enhanced dual-modal magnetic resonance and fluorescence imaging

Abstract

We report a class of multi-functional core-shell nanoarchitectures, consisting of silica nanospheres as the core and GdO:Dy nanocrystals as the ultra-thin shell, that enable unique multi-color living cell imaging and remarkable in vivo magnetic resonance imaging. These types of targeted cell imaging nanoarchitectures can be used as a variety of fluorescence nanoprobes due to the multi-color emissions of the GdO:Dy nanophosphor. We also proposed a strategy of modulating core-shell structure design to achieve an enhanced magnetic resonance contrast ability of GdO nanoagents, and the classical Solomon-Bloembergen-Morgan theory was applied to explicate the mechanism underlying the enhancement. The as-synthesized ligand-free nanomaterial possesses a suitable particle size for cellular uptake as well as avoiding penetrating the blood-brain barrier with good water-solubility, stability, dispersibility and uniformity. The extremely low cytotoxicity and favorable biocompatibility obtained from in vitro and in vivo bioassays of the as-designed nanoparticles indicate their excellent potential as a candidate for functioning as a targeted nanoprobe.

Facile Room-Temperature Synthesis of Cerium Carbonate and Cerium Oxide Nano- and Microparticles Using 1,1′-Carbonyldiimidazole and Imidazole in a Nonaqueous Solvent

“…69 In addition, peaks at 500−600 cm −1 for the O−Ce−O stretching vibration, 70,71 peaks at ∼1380 cm −1 for the vibration mode of Ce−O−Ce, 72,73 and small peaks at 1050 cm −1 for physical absorption of water 74 ) are found in the spectra of CeCb nanoplates, CeCb nanosaucers, and Ce-CDI-IM CeONPs, but not in Ce-IM CeONPs. 75,76 In the spectrum of Ce-IM CeONPs, a sharp peak for the presence of nitrate ions on the surface of nanoparticles appears at 1382 cm −1 , suggesting that there is a difference in surface properties between Ce-IM CeONPs and Ce-CDI-IM CeONPs. 70 Thermogravimetric analysis (TGA) analysis shows a similar initial weight loss due to the desorption of water below 200 °C for all particles, and differing weight losses above 200 °C depending on the type of nanoparticles (Figure 5b).…”

Nanoparticle-Based Paramagnetic Contrast Agents for Magnetic Resonance Imaging

“…PEGylated NaGdF 4 : Dy nanoprobes as both dual-modal T 1 - T 2 and MRI/CT agents were produced by Jin et al T 1 -weighted contrast is provided by the presence of Gd 3+ ions with T 2 -weighted contrast promoted by the doped Dy 3+ ions, which also facilitates the use of the nanoprobe for CT imaging [66]. Dysprosium has been used to dope Gd 2 O 3 nanoparticles resulting in dual-modal MR/fluorescence imaging [67]. These particles contain a silica core encapsulated by a Gd 2 O 3 : Dy 3+ nanoshell.…”

Electronic structure, charge transfer, and intrinsic luminescence of gadolinium oxide nanoparticles: Experiment and theory

“…In reality, gadolinium was never found as a pure free metal in nature up to present, so the most common chemical form the gadolinium oxide (Gd 3+ ) is considered. Currently, this oxide is effectively employed in other equally important applications, e.g., magnetic resonance and fluorescence imaging [2], fabrication of the base for Judd-Ofelt high-efficiency luminescent devices [3], doping-modification of thermally treated nanocomposites [4], semi-commercial manufacturing of magnetocaloric materials [5][6], etc. These abundant and promising applications of Gd 2 O 3 appear to be directly linked with its high chemical activity and structural specificity.…”