Exposure of engineered nanoparticles to human lung epithelial cells: Influence of chemical composition and catalytic activity on oxidative stress
Exposure of engineered nanoparticles to human lung epithelial cells: Influence of chemical composition and catalytic activity on oxidative stress
复制标题
DOI：
10.1021/es062629t
复制
发表时间：
2007-06-01
影响因子：
11.4
通讯作者：
Stark, Wendelin J.
中科院分区：
文献类型：
--
作者：
Limbach, Ludwig K.;Wick, Peter;Stark, Wendelin J.
纳米粒子的化学和催化活性极大地促进了目前对工程纳米材料的巨大兴趣，并经常作为功能材料设计的指导原则。由于最近有证据表明，这种活性物质可以进入细胞或生物体，本研究调查了在体外暴露于含铁、钴、锰和二氧化钛的二氧化硅纳米颗粒和相应的纯氧化物后细胞内的氧化水平。由此产生的氧化应激被定量地测量为活性氧物种(ROS)的释放。使用具有相同形态、相似大小、形状和团聚程度的完全表征的纳米颗粒，可以分离物理效应(颗粒吸收、团聚、沉淀的速率)和化学效应(氧化作用)。三组对照实验阐明了纳米颗粒作为重金属吸收载体的作用，并排除了生物检测对纳米材料的潜在干扰。目前的结果表明，这些颗粒可以通过特洛伊木马类型的机制有效地进入细胞，这种机制在钴或锰的情况下引发的氧化应激比暴露在相同金属水溶液中的参考培养物高出8倍。一项用于工业精细化学合成的含铁纳米颗粒的系统研究表明，催化活性的存在可以强烈地改变纳米材料的破坏作用。这表明，纳米材料的积极发展及其风险评估应考虑纳米材料的化学和催化特性，而不仅仅是关注尺寸、形状和团聚程度等物理特性。
The chemical and catalytic activity of nanoparticles has strongly contributed to the current tremendous interest in engineered nanomaterials and often serves as a guiding principle for the design of functional materials. Since it has most recently become evident that such active materials can enter into cells or organisms, the present study investigates the level of intracellular oxidations after exposure to iron-, cobalt-, manganese-, and titania-containing silica nanoparticles and the corresponding pure oxides in vitro. The resulting oxidative stress was quantitatively measured as the release of reactive oxygen species (ROS). The use of thoroughly characterized nanoparticles of the same morphology, comparable size, shape, and degree of agglomeration allowed separation of physical (rate of particle uptake, agglomeration, sedimentation) and chemical effects (oxidations). Three sets of control experiments elucidated the role of nanoparticles as carriers for heavy metal uptake and excluded a potential interference of the biological assay with the nanomaterial. The present results indicate that the particles could efficiently enter the cells by a Trojan-horse type mechanism which provoked an up to eight times higher oxidative stress in the case of cobalt or manganese if compared to reference cultures exposed to aqueous solutions of the same metals. A systematic investigation on iron-containing nanoparticles as used in industrial fine chemical synthesis demonstrated that the presence of catalytic activity could strongly alter the damaging action of a nanomaterial. This indicates that a proactive development of nanomaterials and their risk assessment should consider chemical and catalytic properties of nanomaterials beyond a mere focus on physical properties such as size, shape, and degree of agglomeration.