Water‐Soluble Ultra‐Small Manganese Oxide Surface Doped Gadolinium Oxide (Gd₂O₃@MnO) Nanoparticles for MRI Contrast Agent

Abstract

We have developed ultra‐small gadolinium oxide (Gd2O3) nanoparticles, which are surface‐doped with manganese oxide (MnO) (abbreviated as Gd2O3@MnO). The surface‐doped nanoparticles ranged from 1 to 2 nm in diameter. They were further coated with hydrophilic biocompatible lactobionic acid. In‐vitro tests of the sample solution indicated clear dose‐dependent contrast enhancements in both T1 and T2 map images, showing that the nanoparticles may be used as both T1 and T2 MRI contrast agents. Their performance as a T1 MRI contrast agent was proved in vivo through T1 MR images of a mouse.

Recent Advances in Gadolinium Based Contrast Agents for Bioimaging Applications

“…Choi et al developed surface-doped with manganese oxide (MnO) Gd-NPs abbreviated as Gd-NPs@MnO ranging from 1 to 2 nm in diameter, coated with hydrophilic biocompatible compound, lactobionic acid (LA). In-vitro studies revealed dose-dependent contrast enhancements in both T 1 and T 2 map images, establishing their potential as both T 1 and T 2 MRI CAs [151]. Mixed Zn(II)/Gd(III) oxide NPs with approximately 8 mole% of Zn with an average diameter of 2.1 nm were synthesized by Tegafaw et al in their studies.…”

Paramagnetic nanoparticles as potential MRI contrast agents: characterization, NMR relaxation, simulations and theory

“…In recent years, different groups [31][32][33][34][35] have produced and characterized paramagnetic rare-earth-containing particles, reporting interesting properties for MRI. Gadolinium oxide and hydroxide particles were shown to present rather efficient T 1 relaxation, with relaxivities ranging from 4 to 40 s -1 mM -1 at 1.5 T. On the contrary, dysprosium oxide particles have almost negligible longitudinal relaxivity at all fields, but they could represent an alternative T 2 contrast agent, especially for high magnetic fields, since their transverse relaxivity increases with the field as first shown at high fields by Norek et al [7] and later confirmed at low and intermediate fields and also for gadolinium hydroxide particles [9].…”

Synthesis, MR Relaxivities, and In Vitro Cytotoxicity of 3,5-Diiodo-L-tyrosine-Coated Gd2O3 Nanoparticles

“…Surfacecoated magnetic nanoparticles have been intensively investigated as MRI contrast agents because they often showed higher water proton relaxivities than molecular chelates. Until now, the iron oxide nanoparticles [7][8][9], the manganese oxide nanoparticles [10][11][12], the gadolinium oxide nanoparticles [13][14][15][16], and the gadolinium compound nanoparticles [17][18][19] have been investigated.…”