不同电荷表面活性剂影响下纳米氧化锌对小球藻的毒性效应与细胞分布  

The toxic effect and cell distribution of nano-zinc oxide on Chlorella vulgaris under the presence of different-charged surfactants

作　　者：顾睿敏 谢琪婷 孟玉芳 周琼芝 葛飞 GU Ruimin;XIE Qiting;MENG Yufang;ZHOU Qiongzhi;GE Fei(College of Environment and Resources,Xiangtan University,Xiangtan,411105,China)

机构地区：[1]湘潭大学环境与资源学院,湘潭411105

出　　处：《环境化学》2023年第5期1753-1762,共10页Environmental Chemistry

基　　金：国家自然科学基金(22076160)资助.

摘　　要：水环境中的带电物质可改变可溶性纳米颗粒的理化性质和累积分布,从而影响纳米颗粒对水生生物的毒性效应.本文探究了3种不同电荷表面活性剂,阳离子型的十六烷基三甲基氯化铵(CTAC)、阴离子型的十二烷基苯磺酸钠(SDBS)、非离子型的聚乙二醇辛基苯基醚(TX-100)存在下纳米氧化锌(nZnO)对小球藻(Chlorella vulgaris)的毒性效应,探明了3种表面活性剂对nZnO性质(电位粒径、Zn^(2+)溶出等)及Zn元素细胞分布的影响.结果表明,带有不同电荷的表面活性剂与nZnO复合具有不同的联合毒性效应及机制.阳离子型CTAC促进nZnO的团聚并抑制Zn^(2+)的溶出,增强nZnO与藻细胞间的静电相互作用,使细胞表面吸附的颗粒态nZnO增加,其联合毒性表现为拮抗作用;阴离子型SDBS促进nZnO的分散和Zn^(2+)的溶出,增强nZnO与藻细胞间的静电排斥,使细胞内Zn^(2+)含量增加,其联合毒性表现为协同作用;非离子型TX-100对Zn^(2+)的细胞分布无显著影响,可能是通过空间位阻作用减少nZnO颗粒与细胞接触,使细胞内颗粒态nZnO降低,其联合毒性表现为拮抗作用.研究结果为更准确、真实地评价纳米颗粒在含有不同电荷物质的水环境中的生态风险提供了理论依据.The charged species in aqueous environments can alter the physicochemical properties,accumulation,and distribution of solubel nanoparticles,thereby affecting their toxicity on aquatic life.This study investigated the toxicity of zinc oxide nanoparticles(nZnO)on Chlorella vulgaris(C.vulgaris)under the stress of three different-charged surfactants,including the cationic surfactant cetyltrimethyl ammonium chloride(CTAC),anionic surfactant sodium dodecyl benzene sulfonate(SDBS),and nonionic surfactant octyl phenoxy polyethoxyethanol(TX-100).Meanwhile,we determined the effect of these surfactants on the properties of nZnO(potential,particle size,dissolution of Zn^(2+),etc.)and the intracellular distribution of Zn.Results showed that nZnO presented different combined toxicities and mechanisms after interacting with different-charged surfactants.Cationic CTAC promoted the agglomeration of nZnO but inhibited the dissolution of Zn^(2+).Moreover,CTAC enhanced the electrostatic attraction between nZnO and the algal cells,reducing the accumulation of nZnO in cells.This indicated an antagonistic effect of nZnO and CTAC on algal growth.In contract,a synergistic effect of anionic SDBS and nZnO was comfirmed because SDBS promoted the dispersion and dissolution of nZnO,and increased intracellular accumulation of Zn^(2+).Furthermore,nonionic TX-100 exhibited no significant effect on the cell distribution of Zn^(2+)and decreased intracellular accumulation of granular nZnO due to the steric hindrance.Thus the combined toxicity of nZnO and TX-100 on C.vulgaris exhibited an antagonistic effect.These results will provide more accurate and authentic evidence of the biological effects of nanoparticles in aqueous environments with different charged species.

关 键 词：纳米氧化锌 不同电荷表面活性剂 毒性效应 细胞分布 致毒机制 

分 类 号：X171.5[环境科学与工程—环境科学]