Single Molecular Wells-Dawson-Like Heterometallic Cluster for the In Situ Functionalization of Ordered Mesoporous Carbon: A T1- and T2- Weighted Dual-Mode Magnetic Resonance Imaging Agent and Drug Delivery System

摘要

Developing a feasible way to prepare highly dispersed heterometallic nanoparticles incorporated in porous carbon composites is of significant importance for multifunctional materials. In this work, heterometallic gamma-Fe2O3 and GdPO4 nanoparticles that are incorporated in ordered mesoporous carbon composites are facilely prepared by a one-pot in situ method using a Wells-Dawson-like cluster of [Fe6Gd6(mu(3)-O)(2)(CO3)(O3PPh)(6)((O2CBu)-Bu-t)(18)] ({Fe6Gd6P6} for short) as the precursor. It is verified that the gamma-Fe2O3 and GdPO4 nanoparticles are highly dispersed and embedded into the carbon matrix with a particle size smaller than 5 nm, even when the carbon matrix is changed from 2D hexagonal P6mm to 3D body-centered cubic Im-3m symmetry. Additionally, a formation mechanism is proposed. Furthermore, dual-mode magnetic resonance (MR) imaging and drug carrier properties are evaluated by in vitro experiments, which show a satisfactory T1- and T2- weighted MR imaging effect with r(1) and r(2) relaxivity values of 2.7 and 183.7 mM(-1) s(-1), respectively, and doxorubicin hydrochloride carrier amount of 102 mg g(-1), identifying a combined function for potential diagnostic and therapy.