Gadolinium oxide nanoplates with high longitudinal relaxivity for magnetic resonance imaging

摘要: Molecular-based contrast agents for magnetic resonance imaging (MRI) are often characterized by insufficient relaxivity, thus requiring the systemic injection of high doses to induce sufficient enhancement at target site. In this work, gadolinium oxide (Gd2O3) nanoplates produced via a thermal decomposition method. The have core diameter varying from 2 22 nm, thickness 1 nm and coated with either an oleic acid bilayer or octylamine modified poly(acrylic acid) (PAA–OA) polymer layer. For smaller nanoplates, longitudinal relaxivities (r1) 7.96 47.2 (mM s)−1 were measured 1.41 T PAA–OA coating, respectively. These values moderately reduce as size Gd2O3 increases, always larger coating. Cytotoxicity studies on human dermal fibroblast cells documented no significant toxicity, 100% cell viability preserved up 250 μM nanoplates. Given 10 times increase in relaxivity over commercially available Gd-based molecular favorable toxicity profile, could represent new class highly effective T1 MRI agents.