粒径和包裹物对纳米银在海洋微藻中的毒性影响  

Contribution of Particle Size and Surface Coating of Silver Nanoparticles to Its Toxicity in Marine Diatom Skeletonema costatum

作　　者：黄俊[1,2] 衣俊 强丽媛 程金平[1,2] 

机构地区：[1]华东师范大学河口海岸学国家重点实验室,上海200062 [2]香港城市大学深圳研究院,深圳518057

出　　处：《环境科学》2016年第5期1968-1977,共10页Environmental Science

基　　金：国家自然科学基金项目(41101489);广东省自然科学基金项目(s2012010010847);教育部新世纪优秀人才计划项目(NECT-12-0181);河口海岸学国家重点实验室自主课题项目(2012RCDW-01)

摘　　要：纳米银由于其独特的抗菌特性广泛应用于工商业领域.通过研究3种不同粒径和包裹物的纳米银对典型海洋微藻中肋骨条藻(Skeletonema costatum)的毒性效应,进一步丰富纳米银对藻类毒性效应及其作用机制的认识.结果表明3种纳米银对硅藻细胞生长都有不同程度的生长抑制效应,其毒性大小依次为10 nm-OA>10 nm-PVP>20 nm-PVP.在细胞毒性方面,相同粒径的聚乙烯吡咯烷酮(PVP)包裹的纳米银比油胺包裹(OA)的纳米银毒性更小;而相同包裹物的10 nm和20 nm两种尺寸的纳米银的毒性效应主要取决于其在水环境中的粒径和浓度,在浓度小于500μg·L^(-1)时,大粒径的纳米银毒性更大;在浓度≥500μg·L^(-1)时,小粒径的纳米银毒性更大.在光合毒性方面,50μg·L^(-1)的10 nm-PVP显著上调3Hfcp A的表达(P<0.05)和显著下调D1的表达(P<0.05),10 nm-OA在浓度为500μg·L^(-1)显著上调3Hfcp A的表达(P<0.05),而20nm-PVP处理组没有显著性变化,说明光合作用相关基因的表达对小粒径PVP包裹的纳米银更敏感.本研究结果表明,纳米银对海洋微藻的毒性是由粒径大小、包裹物类型、暴露介质以及暴露浓度等多方面因素共同决定的.纳米银的粒径越小毒性越大,粒径对纳米银的毒性效应影响很大;而包裹物通过影响纳米银在水介质中的粒径大小间接影响纳米银的毒性效应.Due to the unique antibacterial properties, silver nanoparticles （AgNPs） have been widely used in commercial applications. In this study, the toxicity of three kinds of AgNPs with different sizes and surface coatings to marine diatom Skeletonema costatum （ S. costatum） was studied, which was one of the dominant species in estuarine and coastal areas. All three kinds of tested AgNPs inhibited the growth of exposed S. costatum under acute exposure condition, and the order of toxicity was lOnm-OA 〉 10nm-PVP 〉 20nm-PVP. Given the condition of similar particle size, oil amine surface coated AgNPs were more toxic than polyvinyl pyrrolidone （PVP） surface coated AgNPs in S. costatum in term of cytotoxicity. With the same surface coating, the toxicity of AgNPs in S. costatum was affected by its hydrodynamic diameter and exposure concentrations. When the concentration of AgNPs was less than 500 μg·L^-1, larger sized AgNPs showed greater toxicity; When the concentration was greater than or equal to 500 μg·L^-1, smaller AgNPs exhibited greater toxicity. At molecular level, 50 μg·L^-1 10nm-PVP significantly upregulated expression level of 3HfcpA （P 〈 0. 05 ） and significantly downregulated expression level of D1 （ P 〈 0.05 ） , and 500μg·L^-1 10nm-OA significantly upregulated 3HfcpA expression （ P 〈 0.05） , while 20nm-PVP treatment group didn＇t show any significant change. Exposed diatom demonstrated sensitive photosynthesis response to small size and PVP coated silver nanoparticles at molecular level. This study suggested that the toxicity of AgNPs to marine microalgae was largely controlled by the particle size, surface coating, exposure medium, exposure concentration and other factors. The smaller the particle size, the greater the toxicity of AgNPs, and the particle size of AgNPs played an important role in the toxicity of AgNPs in marine diatom S. costatum.

关 键 词：纳米银 海洋微藻 粒径效应 包裹物效应 毒性比较 

分 类 号：X171.5[环境科学与工程—环境科学]