Gadolinium-conjugated PLA-PEG nanoparticles as liver targeted molecular MRI contrast agent
Gadolinium-conjugated PLA-PEG nanoparticles as liver targeted molecular MRI contrast agent
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DOI：
10.3109/1061186x.2010.531727
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发表时间：
2011-09-01
影响因子：
4.5
通讯作者：
Lu, Zaijun
中科院分区：
文献类型：
--
作者：
Chen, Zhijin;Yu, Dexin;Lu, Zaijun
通过将钆（Gd）螯合基团偶联到具有生物相容性的聚l -丙交酯-聚乙二醇（PLA-PEG）纳米颗粒上，制备了一种靶向肝脏的纳米颗粒磁共振成像（MRI）造影剂。采用溶剂扩散法将聚乳酸-聚乙二醇偶联二乙烯三氨基五乙酸（DTPA）制备成聚乳酸-聚乙二醇-DTPA纳米粒子，并将Gd与聚乳酸-聚乙二醇-DTPA纳米粒子表面展开的DTPA螯合负载在纳米粒子上。纳米颗粒的平均尺寸为265.9 +/- 6.7 nm。测定gd标记纳米粒子的弛豫度，并评价其在大鼠体内的分布。与传统造影剂（Magnevist）相比，gd标记的PLA-PEG纳米颗粒在肝脏靶向能力和成像信号强度方面均有显著增强。在3t下，Gd标记的纳米颗粒每[Gd]的T-1和T-2弛豫度分别为18.865 mM(-1) s和24.863 mM(-1) s（-1）。与Gd-DTPA相比，gd标记的PLA-PEG纳米颗粒在体内的信号强度更强，T-1称重时间持续4.5 h。与Magnevist注射剂相比，gd标记的PLA-PEG纳米颗粒在大鼠体内的肝脏靶向效率为14.57。因此，gd标记的纳米颗粒具有作为靶向性分子MRI造影剂进一步临床应用的潜力。
A nanoparticle magnetic resonance imaging (MRI) contrast agent targeted to liver was developed by conjugation of gadolinium (Gd) chelate groups onto the biocompatible poly(L-lactide)-block-poly (ethylene glycol) (PLA-PEG) nanoparticles. PLA-PEG conjugated with diethylenetriaminopentaacetic acid (DTPA) was used to formulate PLA-PEG-DTPA nanoparticles by solvent diffusion method, and then Gd was loaded onto the nanoparticles by chelated with the unfolding DTPA on the surface of the PLA-PEG-DTPA nanoparticles. The mean size of the nanoparticles was 265.9 +/- 6.7 nm. The relaxivity of the Gd-labeled nanoparticles was measured, and the distribution in vivo was evaluated in rats. Compared with conventional contrast agent (Magnevist), the Gd-labeled PLA-PEG nanoparticles showed significant enhancement both on liver targeting ability and imaging signal intensity. The T-1 and T-2 relaxivities per [Gd] of the Gd-labeled nanoparticles was 18.865 mM(-1) s(-1) and 24.863 mM(-1) s(-1) at 3 T, respectively. In addition, the signal intensity in vivo was stronger comparing with the Gd-DTPA and the T-1 weight time was lasting for 4.5 h. The liver targeting efficiency of the Gd-labeled PLA-PEG nanoparticles in rats was 14.57 comparing with Magnevist injection. Therefore, the Gd-labeled nanoparticles showed the potential as targeting molecular MRI contrast agent for further clinical utilization.