Liu Dun, Wang Lijun, Wang Zhigang, Cuschieri Alfred
Institute for Medical Science and Technology (IMSaT), University of Dundee, Wilson House, 1 Wurzburg Loan, Dundee Medipark, Dundee, DD2 1FD, UK.
Nanoscale Res Lett. 2012 Jul 2;7(1):361. doi: 10.1186/1556-276X-7-361.
To date, there has not been an agreement on the best methods for the characterisation of multi-walled carbon nanotube (MWCNT) toxicity. The length of MWCNTs has been identified as a factor in in vitro and in vivo studies, in addition to their purity and biocompatible coating. Another unresolved issue relates to the variable toxicity of MWCNTs on different cell types. The present study addressed the effects of MWCNTs' length on mammalian immune and epithelial cancer cells RAW264.7 and MCF-7, respectively. Our data confirm that MWCNTs induce cytotoxicity in a length- and cell type-dependent manner. Whereas, longer (3 to 14 μm) MWCNTs exert high toxicity, especially to RAW264.7 cells, shorter (1.5 μm) MWCNTs are significantly less cytotoxic. These findings confirm that the degree of biocompatibility of MWCNTs is closely related to their length and that immune cells appear to be more susceptible to damage by MWCNTs. Our study also indicates that MWCNT nanotoxicity should be analysed for various components of cellular response, and cytotoxicity data should be validated by the use of more than one assay system. Results from chromogenic-based assays should be confirmed by trypan blue exclusion.
迄今为止，关于多壁碳纳米管（MWCNT）毒性特征的最佳方法尚未达成共识。除了纯度和生物相容性涂层外，MWCNT的长度已被确定为体外和体内研究中的一个因素。另一个未解决的问题与MWCNT对不同细胞类型的可变毒性有关。本研究分别探讨了MWCNT长度对哺乳动物免疫细胞和上皮癌细胞RAW264.7和MCF-7的影响。我们的数据证实，MWCNT以长度和细胞类型依赖性方式诱导细胞毒性。较长（3至14μm）的MWCNT具有高毒性，尤其是对RAW264.7细胞，而较短（1.5μm）的MWCNT细胞毒性明显较小。这些发现证实，MWCNT的生物相容性程度与其长度密切相关，并且免疫细胞似乎更容易受到MWCNT的损伤。我们的研究还表明，应针对细胞反应的各种成分分析MWCNT纳米毒性，并且细胞毒性数据应通过使用不止一种检测系统进行验证。基于显色法的检测结果应通过台盼蓝排斥法进行确认。
