TiO_2、SiO_2、Fe纳米及微米粉体对红细胞毒性作用的比较

Comparative study on the cytotoxicity of nano-sized and micro-sized powders of titanium dioxide,silicon dioxide and iron on erythrocytes

目的 应用体外实验,比较纳米级二氧化钛(nm -TiO2 )、二氧化硅(nm -SiO2 )、铁(nm- Fe)及其微米粉体悬液与大鼠红细胞接触后其脂质过氧化和溶血作用变化情况。方法 将不同浓度的nm -TiO2 、nm -SiO2 、nm- Fe及其微米粉体悬液与大鼠红细胞温育后,测定上清液中MDA含量和相对溶血率。结果 在本实验所用浓度范围内,nm -SiO2 、μm -SiO2 和nm -Fe均能诱导红细胞氧化溶血,使MDA含量和相对溶血率明显升高,并呈量效关系,其中nm- SiO2 的细胞毒性作用最强;nm -TiO2 、μm- TiO2 和μm -Fe诱导红细胞MDA含量和相对溶血率虽也有剂量依赖趋势,但均低于5 %的国家标准,可视为无溶血反应;浓度相同时,SiO2 和Fe纳米粉体组MDA含量和相对溶血率比微米粉体组高(P <0 . 0 5 ) ,而TiO2 则是微米粉体组高于纳米粉体组(P <0 . 0 5 )。结论 同一材料不同粒径粉体之间和不同纳米粉体物质之间的红细胞毒性作用存在差异。

Objective To compare the changes of hemolysis and malondialdehyde(MDA)generation in rat erythrocytes respectively treated with nano-sized and micro-sized powders of titanium dioxide,silicon dioxide and iron in vitro.Method The erythrocytes of rats were incubated with different concentration powders of those nano-sized and micro-sized substances mentioned above,then determined the changes of hemolysis rates and MDA levels in culture media.Result In the concentration ranges used by this study,nm-SiO_2,μm-SiO_2 and nm-Fe all could induce the increase of hemolytic rates and MDA levels,which had some dose-response relationship.Among these chemicals,nm-SiO_2 showed the most strong cytotoxicity,nm-TiO_2,μm-TiO_2 and μm-Fe also had some effect on inducing MDA generation,but the increases of hemolytic rates were still less than 5%,suggesting a negative effect on hemolysis.The results also showed that the MDA levels and hemolytic rates in nm-SiO_2 and nm-Fe treated groups were significantly higher than those of micro-sized powders under the same dose levels(P<0.05),while MDA generations and hemolytic rates in nm-TiO_2 treated group were less than those μm-TiO_2 treated group(P<0.05).Conclusion There are some differences in the cytotoxicity between nano-sized and micro-sized powders even the same chemicals mentioned above.