文献类型：期刊文献

英文题名：Ultrasmall Water-Soluble and Biocompatible Magnetic Iron Oxide Nanoparticles as Positive and Negative Dual Contrast Agents

作者：Li, Zhen[1];Yi, Pei Wei[2];Sun, Qiao[3];Lei, Hao[2];Zhao, Hong Li[4];Zhu, Zhong Hua[5];Smith, Sean C.[3];Lan, Min Bo[4];Lu, Gao Qing (Max)[1]

机构：[1]Univ Queensland, ARC Ctr Excellence Funct Nanomat, Australian Inst Bioengn & Nanotechnol, Brisbane, Qld 4072, Australia;[2]Chinese Acad Sci, State Key Lab Magnet Resonance & Atom & Mol Phys, WuHan Inst Phys & Math, Wuhan 430071, Peoples R China;[3]Univ Queensland, Ctr Computat Mol Sci, Australian Inst Bioengn & Nanotechnol, Brisbane, Qld 4072, Australia;[4]E China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China;[5]Univ Queensland, Sch Chem Engn, Brisbane, Qld 4072, Australia

年份：2012

卷号：22

期号：11

起止页码：2387

外文期刊名：ADVANCED FUNCTIONAL MATERIALS

收录：;EI(收录号：20122315103044);WOS:【SCI-EXPANDED(收录号:WOS:000304749600019)】；

基金：Z.L. gratefully acknowledges the scientific visit to China sponsored by Australia Academy of Science, and the award of a Queensland Smart Future Fellowship, a University of Queensland (UQ) early-career-research (ECR) grant and a UQ new staff research startup grant. Support from the Australian Research Council (through its centres program) to the ARC Centre of Excellence for Functional Nanomaterials is also gratefully acknowledged. H. L. acknowledges the support from Natural Science Foundation of China grant (20921004).

语种：英文

外文关键词：dual contrast agents; iron oxide; magnetic resonance imaging; magnetic nanoparticles; coprecipitation

摘要：Monodispersed water-soluble and biocompatible ultrasmall magnetic iron oxide nanoparticles (UMIONs, D = 3.3 +/- 0.5 nm) generated from a high-temperature coprecipitation route are successfully used as efficient positive and negative dual contrast agents of magnetic resonance imaging (MRI). Their longitudinal relaxivity at 4.7 T (r1 = 8.3 mM-1 s-1) is larger than that of clinically used T1-positive agent Gd-DTPA (r1 = 4.8 mM-1 s-1), and three times that of commercial contrast agent SHU-555C (r1 = 2.9 mM-1 s-1). The transversal relaxivity (r2 = 35.1 mM-1 s-1) is six times that of Gd-DTPA (r2 = 5.3 mM-1 s-1), half of SHU-555C (r2 = 69 mM-1 s-1). The in vivo results show that the liver signal from T1-weighted MRI is positively enhanced 26%, and then negatively decreased 20% after injection of the iron oxide nanoparticles, which is stronger than those obtained from Gd-DTPA (<10%) using the same dosage. The kidney signal is positively enhanced up to 35%, similar to that obtained from Gd-DTPA. Under T2-weighted conditions, the liver signal is negatively enhanced ?70%, which is significantly higher than that from Gd-DTPA (?6%). These results demonstrate the great potential of the UMIONs in dual contrast agents, especially as an alternative to Gd-based positive contrast agents, which have risks of inducing side effects in patients.