纳米四氧化三铁吸附水中六价铬后的复合物对HEK293细胞的毒性研究

磁性纳米粒子是一种环境友好型吸附剂,广泛应用于废水中重金属的处理。目前,有不少关于纳米粒子毒性的研究,但对处理后的纳米粒子和金属的复合物的毒性却鲜有研究。本文利用纳米四氧化三铁(MNPs)吸附水中的铬离子,以人胚胎肾细胞HEK293为生物模型,通过测定细胞活力、活性氧含量以及细胞摄取量等试验,评估磁性纳米四氧化三铁吸附六价铬后的复合产物对HEK293细胞的毒性。实验结果显示:在本实验浓度和作用时间下,Cr(Ⅵ)离子能够进入细胞,产生氧化应激,并引起细胞毒性;与Cr(Ⅵ)离子相比,磁性纳米四氧化三铁吸附Cr(Ⅵ)后的修复产物MNPs/Cr(Ⅵ)对HEK293细胞无明显毒性效应,MNPs/Cr(Ⅵ)复合物在细胞内的摄取极少,只有极少数颗粒通过内吞的方式进入细胞,且没有进入细胞核内。因此,在本实验的作用浓度和时间下,利用MNPs吸附水环境中Cr(Ⅵ)后的复合物对HEK293细胞没有明显毒性,本研究为深化了解MNPs及其重金属复合物对环境的影响提供了实验依据和参考价值。

Toxicity of Composite of Cr(VI) Adsorbed by Magnetite Fe3O4 Nanoparticles on HEK293

Magnetite nanoparticle is an environmentally friendly adsorbent which is widely used for the treatment of heavy metals in wastewater. Recently, significant research efforts have been made toward the investigation of nanoparticle toxicity, whereas very little attention has been paid to nanoadducts though the nanoadduct formations has been broadly used in environmental remediation. This paper aims to elucidate the combined toxicity of magnetite nanoparticles/chromium (MNPs/Cr(VI)) adducts. The cytotoxicity was evaluated by assessing the cell viability, ROS generation, and cellular uptake. The results showed that the toxicity of formed adducts MNPs/Cr(VI) had no obvious toxicity on HEK293 cells when compared to Cr(VI) anions. The cellular uptake of MNPs/Cr(VI) adduct was rare, and only few particles were endocytosed from the extracellular fluid and not accumulated in the cell nucleus. On the other hand, Cr(VI) anions entered cells, generated oxidative stress, and caused cytotoxicity. Therefore, under certain condition, MNPs/Cr(VI) adducts have no obvious toxicity to HEK293 cells. This study provides experimental basis and reference for the deep study of the impact of nanoadducts in environment.