Self-Assembly of PEG-Coated Ceria Nanoparticles Shows Dependence on PEG Molecular Weight and Ageing
Self-Assembly of PEG-Coated Ceria Nanoparticles Shows Dependence on PEG Molecular Weight and Ageing
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DOI：
10.1002/cplu.201500237
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发表时间：
2015-11-01
期刊：
影响因子：
3.4
通讯作者：
Seal, Sudipta
中科院分区：
文献类型：
--
作者：
Neal, Craig J.;Das, Soumen;Seal, Sudipta
以不同分子量（MWs分别为300、600、1500、3000、4000和6000Da）的聚乙二醇（peg）为原料，以水为共溶剂合成氧化铈纳米粒子（CNPs），并对其理化性质，特别是形貌和粒径随时间的变化进行了监测。采用高分辨率透射电子显微镜（HRTEM）对所有溶液进行了分析，并显示了1500MW PEG涂层CNPs的八面体、星形形貌。拉曼和FTIR光谱、HRTEM图像、电导率和电泳迁移率表明，通过分形组装方法，小球形颗粒可以自组装成八面体、星形颗粒。采用动态光散射方法建立了八面体自组装的经验增长模型。由于分子量依赖的物理化学性质，PEG聚合物链长度和CNPs年龄依赖的氧化还原活性限制或允许这种组装。这项研究强调了老化对溶液基纳米粒子的重要性，以及它对长期使用纳米粒子的影响。由于聚乙二醇化纳米颗粒在生物医学应用中有广泛的应用，我们在体外测试了老化颗粒的毒性。
Cerium oxide (ceria) nanoparticles (CNPs) were synthesized in poly(ethylene glycol)s (PEGs) of different molecular weights (MWs; 300, 600, 1500, 3000, 4000, and 6000Da) with water as a cosolvent, and changes in physicochemical properties, especially morphology and size, were monitored as a function of time. High-resolution transmission electron microscopy (HRTEM) was performed for all solutions and revealed octahedral, star morphologies for CNPs coated with 1500MW PEG. Raman and FTIR spectroscopy, HRTEM images, conductivity, and electrophoretic mobility imply the self-assembly of small spherical particles to octahedral, star-shaped particles by means of a fractal assembly method. Dynamic light scattering measures were used to create an empirical growth model of the observed octahedral self-assembly. It was also determined that PEG polymer chain lengths and age-dependent redox activities of CNPs limit or allow this assembly owing to molecular-weight-dependent physicochemical properties. This study highlights the significance of ageing on solution-based nanoparticles and its implications in the use of nanoparticles over long periods of time. As PEG-ylated nanoparticles have found extensive use in biomedical applications, we have tested the aged particles invitro for toxicity.