Far Eastern Federal University, Vladivostok, 690950, Russian Federation; N.I. Vavilov All-Russian Research Institute of Plant Genetic Resources, Saint Petersburg, 190121, Russian Federation.
Research Institute of Science and Technology, Tokai University, Hiratsuka, Kanagawa, 259-1292, Japan; Department of Chemistry, University of Mining and Geology, Sofia, 1700, Bulgaria.
Environ Res. 2020 Jul;186:109513. doi: 10.1016/j.envres.2020.109513. Epub 2020 Apr 14.
This study reports the differences in toxic action between cadmium sulfide (CdS) and zinc sulfide (ZnS) nanoparticles (NPs) prepared by recently developed xanthate-mediated method. The aquatic toxicity of the synthesized NPs on four marine microalgae species was explored. Growth rate, esterase activity, membrane potential, and morphological changes of microalgae cells were evaluated using flow cytometry and optical microscopy. CdS and ZnS NPs demonstrated similar level of general toxicity and growth-rate inhibition to all used microalgae species, except the red algae P. purpureum. More specifically, CdS NPs caused higher inhibition of growth rate for C. muelleri and P. purpureum, while ZnS NPs were more toxic for A. ussuriensis and H. akashiwo species. Our findings suggest that the sensitivity of different microalgae species to CdS and ZnS NPs depends on the chemical composition of NPs and their ability to interact with the components of microalgal cell-wall. The red microalga was highly resistant to ZnS NPs most likely due to the presence of phycoerythrin proteins in the outer membrane bound Zn cations defending their cells from further toxic influence. The treatment with CdS NPs caused morphological changes and biochemical disorder in all tested microalgae species. The toxicity of CdS NPs is based on their higher photoactivity under visible light irradiation and lower dissociation in water, which allows them to generate more reactive oxygen species and create a higher risk of oxidative stress to aquatic organisms. The results of this study contribute to our understanding of the parameters affecting the aquatic toxicity of semiconductor NPs and provide a basis for further investigations.
本研究报告了由最近开发的黄原酸盐介导法制备的硫化镉（CdS）和硫化锌（ZnS）纳米粒子（NPs）的毒性作用差异。探讨了合成 NPs 对四种海洋微藻的水生毒性。使用流式细胞术和光学显微镜评估了 NPs 对微藻细胞生长率、酯酶活性、膜电位和形态变化的影响。CdS 和 ZnS NPs 对所有使用的微藻物种表现出相似水平的一般毒性和生长抑制作用，除了红藻 P. purpureum 外。更具体地说，CdS NPs 对 C. muelleri 和 P. purpureum 的生长率抑制作用更高，而 ZnS NPs 对 A. ussuriensis 和 H. akashiwo 物种的毒性更高。我们的研究结果表明，不同微藻物种对 CdS 和 ZnS NPs 的敏感性取决于 NPs 的化学成分及其与微藻细胞壁成分相互作用的能力。红微藻对 ZnS NPs 的高度抗性很可能是由于外膜结合的 Zn 阳离子中存在藻红蛋白，从而保护其细胞免受进一步的毒性影响。CdS NPs 的处理导致所有测试的微藻物种发生形态变化和生化紊乱。CdS NPs 的毒性基于其在可见光照射下更高的光活性和在水中更低的离解度，这使其能够产生更多的活性氧物种，并对水生生物造成更高的氧化应激风险。本研究的结果有助于我们了解影响半导体 NPs 水生毒性的参数，并为进一步的研究提供了基础。
