Journal of Experimental Nanoscience ( IF 2.8 ) Pub Date : 2018-04-09 , DOI: 10.1080/17458080.2018.1449023 Zhenhong Wang 1, 2 , Zhuanxi Luo 1 , Yamen Yan 1
Little information is available on Titanium dioxide nanoparticles (nTiO2) behavior in different culture media for aquatic organisms. This study aimed to accurately evaluate nTiO2 dispersion and sedimentation in common freshwater algae (BG-11) and daphnia aquatic (SM7) culture media. We additionally investigated potential mechanisms of nTiO2 stability under arsenate influence. Results showed that high ionic strength in culture media was probably a key reason for the acute nTiO2 agglomeration found. Additionally, the hydrodynamic size of nTiO2 suspension in the presence of arsenate was significantly larger, increasing with arsenate concentration in ultrapure water. Conversely, the hydrodynamic size in BG-11 and SM7 decreased with arsenate concentration. The nTiO2 sedimentation rate increased significantly with arsenate concentration in ultrapure water but significantly decreased in BG-11 and SM7 culture media. Many nTiO2 remained suspended after initial rapid sedimentation and the slight sedimentation that occurred in the subsequent 24 h, suggesting that algae and daphnia within the water column will be exposed to small nanoparticle aggregates for a long period of time. Such nTiO2 behavior, especially in the presence of arsenate, requires more consideration than the different toxicological results reported in literature.
中文翻译:
砷酸盐存在下二氧化钛纳米粒子在淡水藻类和水蚤水生培养基中的分散和沉降
关于水生生物在不同培养基中的二氧化钛纳米粒子(nTiO 2)行为的信息很少。这项研究旨在准确评估常见的淡水藻类(BG-11)和水蚤(SM7)培养基中nTiO 2的分散和沉降。我们还研究了砷酸盐影响下nTiO 2稳定性的潜在机制。结果表明,培养基中较高的离子强度可能是导致nTiO 2急性团聚的关键原因。此外,nTiO 2的流体动力学尺寸砷酸盐存在下的悬浮液显着更大,随超纯水中砷酸盐浓度的增加而增加。相反,BG-11和SM7中的流体动力学尺寸随砷酸盐浓度的增加而减小。在超纯水中,nTiO 2的沉降速率随砷酸盐浓度的增加而显着增加,但在BG-11和SM7培养基中的沉降则显着降低。在最初的快速沉降和随后的24小时内发生的轻微沉降之后,许多nTiO 2仍然保持悬浮状态,这表明水柱内的藻类和水蚤将长时间暴露于小的纳米颗粒聚集体中。这样的nTiO 2 与文献中报道的不同毒理学结果相比,尤其是在砷酸根存在下,这种行为的发生需要更多的考虑。