Designed Synthesis of CeO2 Nanorods and Nanowires for Studying Toxicological Effects of High Aspect Ratio Nanomaterials
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- 作者：Zhaoxia Ji ; Xiang Wang ; Haiyuan Zhang ; Sijie Lin ; Huan Meng ; Bingbing Sun ; Saji George ; Tian Xia ; Andr茅 E. Nel ; Jeffrey I. Zink
- 刊名：ACS Nano
- 出版年：2012
- 出版时间：June 26, 2012
- 年：2012
- 卷：6
- 期：6
- 页码：5366-5380
- 全文大小：965K
- 年卷期：v.6,no.6(June 26, 2012)
- ISSN：1936-086X
文摘
While it has been shown that high aspect ratio nanomaterials like carbon nanotubes and TiO2 nanowires can induce toxicity by acting as fiber-like substances that damage the lysosome, it is not clear what the critical lengths and aspect ratios are that induce this type of toxicity. To answer this question, we synthesized a series of cerium oxide (CeO2) nanorods and nanowires with precisely controlled lengths and aspect ratios. Both phosphate and chloride ions were shown to play critical roles in obtaining these high aspect ratio nanostructures. High-resolution TEM analysis shows that single-crystalline CeO2 nanorods/nanowires were formed along the [211] direction by an 鈥渙riented attachment鈥?mechanism, followed by Ostwald ripening. The successful creation of a comprehensive CeO2 nanorod/nanowire combinatorial library allows, for the first time, the systematic study of the effect of aspect ratio on lysosomal damage, cytotoxicity, and IL-1尾 production by the human myeloid cell line (THP-1). This in vitro toxicity study demonstrated that, at lengths 鈮?00 nm and aspect ratios 鈮?2, CeO2 nanorods induced progressive pro-inflammatory effects and cytotoxicity. The relatively low 鈥渃ritical鈥?length and aspect ratio were associated with small nanorod/nanowire diameters (6鈥?0 nm), which facilitates the formation of stacking bundles due to strong van der Waals and dipole鈥揹ipole attractions. Our results suggest that both length and diameter components of aspect ratio should be considered when addressing the cytotoxic effects of high aspect ratio materials.