Persistence of singly dispersed silver nanoparticles in natural freshwaters, synthetic seawater, and simulated estuarine waters
Persistence of singly dispersed silver nanoparticles in natural freshwaters, synthetic seawater, and simulated estuarine waters
复制标题
DOI：
10.1016/j.scitotenv.2011.03.020
复制
发表时间：
2011-05-15
影响因子：
9.8
通讯作者：
Hackley, Vincent A.
中科院分区：
文献类型：
--
作者：
Chinnapongse, Stephanie L.;MacCuspie, Robert I.;Hackley, Vincent A.
本研究通过测量柠檬酸包覆的20纳米银纳米粒子（AgNPs）在天然淡水和合成水介质中的胶体稳定性，重点关注对其持久性的预测。利用紫外 - 可见吸收光谱、动态光散射和原子力显微镜评估了AgNPs在当地获取的池塘水、单独的中硬配制水或含天然有机物（NOM）的中硬配制水、合成海水以及海水中最常见的单一化学物质中的胶体稳定性。在海水中以及氯化钠浓度大于20 mmol/L的水中，单独分散的AgNPs不稳定，在混合后的前10小时内吸光度趋近于零。将团聚速率作为水化学和NOM的函数进行测试，以此作为一种假设来解释单独分散的AgNPs的消失速率。其他样品，主要是那些盐度较低或含NOM的样品，在长达48小时的时间研究中保持了不同程度的胶体稳定性。这表明一些AgNPs在淡水中可能稳定足够长的时间，从而能够成功进入河口或海洋系统。这些结果应能通过预测柠檬酸包覆的20纳米AgNPs最有可能积累和暴露的水生或土壤环境，更有效地设计纳米环境、健康和安全（nanoEHS）风险评估实验。由爱思唯尔公司出版。
This investigation focuses on predicting the persistence of citrate-capped 20 nm AgNPs by measuring their colloidal stability in natural freshwaters and synthetic aquatic media. Ultraviolet-visible absorbance spectroscopy, dynamic light scattering, and atomic force microscopy were used to evaluate the colloidal stability of AgNPs in locally-obtained pond water, moderately hard reconstituted water alone or with natural organic matter (NOM), synthetic seawater, and also the individual chemicals most prevalent in seawater. Singly dispersed AgNPs in seawater and waters with greater than 20 mmol L-1 sodium chloride were unstable, with the optical absorbance approaching zero within the first ten hours of mixing. Agglomeration rates as a function of water chemistry and NOM are tested as a hypothesis to explain the rates of disappearance of singly dispersed AgNPs. Other samples, mostly those with lower salinity or NOM, maintained varying degrees of colloidal stability during time studies up to 48 h. This indicates likelihood that some AgNPs will be stable long enough in freshwater to successfully enter estuarine or marine systems. These results should enable a more efficient design of nanoEHS risk assessment experiments by predicting the aquatic or soil compartments at greatest potential risk for accumulation of and exposure to citrate capped 20 nm AgNPs. Published by Elsevier B.V.