Qi Yingzhe, Shao Chen, Gu Wei, Li Fuying, Deng Yunlong, Li Hansheng, Ye Ling
School of Chemical Biology and Pharmaceutical Sciences, Capital Medical University, Beijing, P. R. China.
J Mater Chem B. 2013 Apr 7;1(13):1846-1851. doi: 10.1039/c3tb00037k. Epub 2013 Feb 20.
To improve the magnetic properties and MRI contrast effect of FeO superparamagnetic nanoparticles (NPs), a series of oleate-capped, Mn-doped MnFeFeO (x≤ 0.4) NPs was prepared via a thermal decomposition method and subsequently assembled into nanoclusters by the carboxylic silane. The effects of Mn doping and clustering on the magnetization, relaxivity and contrast enhancement of the MnFeFeO (x≤ 0.4) NPs were studied. Our results revealed that the MnFeFeO NPs exhibited the highest saturation magnetization of 82.55 emu g when x = 0.05. Correspondingly, the assembled MnFeFeO nanoclusters showed the highest relaxivity value of 528 (Mn + Fe) mM s and an enhanced MRI contrast in mouse liver. In addition, the MTT and H&E analysis confirmed that MnFeFeO nanoclusters were non-toxic. Therefore, the biocompatible MnFeFeO nanoclusters with superior relaxometric properties hold great potential in serving as a novel MRI nanoprobe.
为了改善FeO超顺磁性纳米颗粒（NPs）的磁性能和磁共振成像（MRI）对比效果，通过热分解法制备了一系列油酸包覆、Mn掺杂的MnFeFeO（x≤0.4）NPs，随后通过羧基硅烷将其组装成纳米团簇。研究了Mn掺杂和团聚对MnFeFeO（x≤0.4）NPs的磁化强度、弛豫率和对比增强的影响。我们的结果表明，当x = 0.05时，MnFeFeO NPs表现出最高饱和磁化强度82.55 emu g。相应地，组装后的MnFeFeO纳米团簇显示出最高弛豫率值528（Mn + Fe）mM⁻¹ s⁻¹，并在小鼠肝脏中增强了MRI对比。此外，MTT和H&E分析证实MnFeFeO纳米团簇无毒。因此，具有优异弛豫性能的生物相容性MnFeFeO纳米团簇在作为新型MRI纳米探针方面具有巨大潜力。
