title: Europium-engineered iron oxide nanocubes with high T1 and T2 contrast abilities for MRI in living subjects.
abstract: Magnetic resonance imaging (MRI) contrast agents with both positive (T1) and negative (T2) contrast abilities are needed in clinical diagnosis for fault-free accurate detection of lesions. We report a facile synthesis of europium-engineered iron oxide (EuIO) nanocubes as T1 and T2 contrast agents for MRI in living subjects. The Eu(iii) oxide-embedded iron oxide nanoparticles significantly increase the T1 relaxivity with an enhanced positive contrast effect. EuIO nanocubes with 14 nm in diameter showed a high r1 value of 36.8 mM(-1) s(-1) with respect to total metal ions (Fe + Eu), which is about 3 times higher than that of Fe3O4 nanoparticles with similar size. Moreover, both r1 and r2 values of EuIO nanocubes can be tuned by varying their sizes and Eu doping ratios. After citrate coating, EuIO nanocubes can provide enhanced T1 and T2 contrast effects in small animals, particularly in the cardiac and liver regions. This work may provide an insightful strategy to design MRI contrast agents with both positive and negative contrast abilities for biomedical applications.
authors: State Key Laboratory of Physical Chemistry of Solid Surfaces, The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. jhgao@xmu.edu.cn.
authors: Lijiao
authors: L
authors: Yang
authors: Zijian
authors: Z
authors: Zhou
authors: Hanyu
authors: H
authors: Liu
authors: Changqiang
authors: C
authors: Wu
authors: Hui
authors: H
authors: Zhang
authors: Guoming
authors: G
authors: Huang
authors: Hua
authors: H
authors: Ai
authors: Jinhao
authors: J
authors: Gao
mesh_terms: D045744:Cell Line, Tumor; D002951:Citrates / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry; D005063:Europium / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D006801:Humans; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology; D010316:Particle Size; D019047:Phantoms, Imaging; D000077559:Sodium Citrate; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D002951:Citrates; D003287:Contrast Media; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C000499:ferric oxide; D000077559:Sodium Citrate; D005063:Europium