Manipulating the surface coating of ultra-small Gd2O3 nanoparticles for improved T1-weighted MR imaging
Manipulating the surface coating of ultra-small Gd2O3 nanoparticles for improved T1-weighted MR imaging
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DOI：
10.1016/j.biomaterials.2013.11.032
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发表时间：
2014-02-01
期刊：
影响因子：
14
通讯作者：
Ding, Jun
中科院分区：
文献类型：
--
作者：
Fang, Jie;Chandrasekharan, Prashant;Ding, Jun
在这篇报道中，单分散的超小Gd 2 O3纳米粒子与疏水性油酸（OA）的覆盖合成的平均粒径为2.9 nm。介绍了两种将表面涂层改性为亲水性以用于生物应用的方法。与OA和十六烷基三甲基溴化铵（CTAB）共包覆的Gd 2 O3（Gd 2 O3-OA-CTAB）相比，聚乙烯吡咯烷酮（PVP）包覆的Gd 2 O3纳米粒子（Gd 2 O3-PVP）在弛豫研究中表现出较短的纵向T-1弛豫时间。Gd 2 O3-PVP在7 T下的纵向弛豫率r（1）为12.1 mm（-1）s（-1），是市售对比剂Magenvist的3倍左右。在HK-2细胞中的体外细胞活力表明，在临床前剂量内，Gd_2O_3-PVP的细胞毒性可忽略不计。在体内的磁共振成像研究的Gd 2 O 3-PVP纳米粒子表现出相当大的信号增强，在肝脏和肾脏的血液循环时间长。值得注意的是，OA封端剂通过Gd 2 O3纳米颗粒表面上的配体交换被PVP取代。PVP的亲水性使Gd 2 O3纳米粒子具有生物应用的极性表面，所得Gd 2 O3-PVP可作为网状内皮细胞活性的体内指示剂。(C)2013爱思唯尔有限公司保留所有权利。
In this report, monodispersed ultra-small Gd2O3 nanoparticles capped with hydrophobic oleic acid (OA) were synthesized with average particle size of 2.9 nm. Two methods were introduced to modify the surface coating to hydrophilic for bio-applications. With a hydrophilic coating, the polyvinyl pyrrolidone (PVP) coated Gd2O3 nanoparticles (Gd2O3-PVP) showed a reduced longitudinal T-1 relaxation time compared with OA and cetyltrimethylammonium bromide (CTAB) co-coated Gd2O3 (Gd2O3-OA-CTAB) in the relaxation study. The Gd2O3-PVP was thus chosen for its further application study in MRI with an improved longitudinal relaxivity r(1) of 12.1 mm(-1) s(-1) at 7 T, which is around 3 times as that of commercial contrast agent Magnevist. In vitro cell viability in HK-2 cell indicated negligible cytotoxicity of Gd2O3-PVP within preclinical dosage. In vivo MR imaging study of Gd2O3-PVP nanoparticles demonstrated considerable signal enhancement in the liver and kidney with a long blood circulation time. Notably, the OA capping agent was replaced by PVP through ligand exchange on the Gd2O3 nanoparticle surface. The hydrophilic PVP grants the Gd2O3 nanoparticles with a polar surface for bio-application, and the obtained Gd2O3-PVP could be used as an in vivo indicator of reticuloendothelial activity. (C) 2013 Elsevier Ltd. All rights reserved.