Department of Public Health, Aarhus University, Bartholins Allé 2, DK-8000 Aarhus C, Denmark.
Toxicol Lett. 2012 Feb 5;208(3):286-92. doi: 10.1016/j.toxlet.2011.11.002. Epub 2011 Nov 11.
The toxicity of silver nanoparticles (AgNPs) has been shown in many publications. Here we investigated to which degree the silver ion fraction of AgNP suspensions, contribute to the toxicity of AgNPs in A549 lung cells. Cell viability assays revealed that AgNP suspensions were more toxic when the initial silver ion fraction was higher. At 1.5μg/ml total silver, A549 cells exposed to an AgNP suspension containing 39% silver ion fraction showed a cell viability of 92%, whereas cells exposed to an AgNP suspension containing 69% silver ion fraction had a cell viability of 54% as measured by the MTT assay. In addition, at initial silver ion fractions of 5.5% and above, AgNP-free supernatant had the same toxicity as AgNP suspensions. Flow-cytometric analyses of cell cycle and apoptosis confirmed that there is no significant difference between the treatment with AgNP suspension and AgNP supernatant. Only AgNP suspensions with silver ion fraction of 2.6% or less were significantly more toxic than their supernatant as measured by MTT assays. From our data we conclude that at high silver ion fractions (≥5.5%) the AgNPs did not add measurable additional toxicity to the AgNP suspension, whereas at low silver ion fractions (≤2.6%) AgNP suspensions are more toxic than their supernatant.
银纳米粒子（AgNPs）的毒性在许多出版物中都有报道。在这里，我们研究了银纳米粒子悬浮液中的银离子部分在多大程度上导致了 AgNPs 对 A549 肺细胞的毒性。细胞活力测定显示，当初始银离子分数较高时，AgNP 悬浮液的毒性更大。在总银浓度为 1.5μg/ml 时，暴露于含有 39%银离子分数的 AgNP 悬浮液中的 A549 细胞的细胞活力为 92%，而暴露于含有 69%银离子分数的 AgNP 悬浮液中的细胞的细胞活力为 54%，这是通过 MTT 测定法测量的。此外，在初始银离子分数为 5.5%及以上时，无 AgNP 的上清液与 AgNP 悬浮液具有相同的毒性。细胞周期和凋亡的流式细胞术分析证实，用 AgNP 悬浮液和 AgNP 上清液处理没有显著差异。只有银离子分数为 2.6%或更低的 AgNP 悬浮液的细胞活力比 MTT 测定法测量的上清液的细胞活力显著更高，表明其毒性更大。根据我们的数据，我们得出结论，在高银离子分数（≥5.5%）下，AgNPs 对 AgNP 悬浮液没有增加可测量的额外毒性，而在低银离子分数（≤2.6%）下，AgNP 悬浮液比其上清液更具毒性。
