Particle size distributions of silver nanoparticles at environmentally relevant conditions
Particle size distributions of silver nanoparticles at environmentally relevant conditions
复制标题
DOI：
10.1016/j.chroma.2009.07.021
复制
发表时间：
2009-12-25
影响因子：
4.1
通讯作者：
Lead, Jamie R.
中科院分区：
文献类型：
--
作者：
Cumberland, Susan A.;Lead, Jamie R.
银纳米颗粒（Ag NP）作为消费品中的抗菌剂越来越受欢迎，但其排放会对环境健康造成风险。与环境相关的归宿和运输研究虽然有限，但对于了解生物利用度和毒理学至关重要。在这项研究中，合成了单分散的 15 nm 柠檬酸盐稳定的银纳米颗粒，对其进行表征，然后在环境相关条件（pH 5 或 8、存在天然有机大分子 (NOM) 以及存在钠或钙）下通过流场流分级 (FIFFF) 进行分级。在低离子强度下，随着 pH 从 5 增加到 8，Ag NP 粒径增大。然而，将离子强度从 10(-3) M Na 更改为 10(-2) M Na 会增加 Ag NP 的不稳定性，并且在 pH 5 时峰丢失，但在腐殖质 (HS) 存在的情况下，可以看到 NP 尺寸减小，很可能是由于扩散层的减少。 Ca2+ 离子的存在，在较高的离子强度下，会导致含有或不含 HS 的溶液 Ag NP 完全损失，很可能是由于聚集所致。在较低的 Ca2+ 离子强度下，Ag NPs 仍然不稳定，但同样，在 H2S 存在下，NPs 很大程度上分散了。 H2S 的存在通过形成表面涂层提高了银纳米颗粒在这些条件下的稳定性，从而实现空间和电荷稳定。这项工作表明，在 H2S 存在的情况下，Ag NP 在水生系统中可以有较长的停留时间，从而可能导致生物利用度增加。 (C) 2009 Elsevier B.V. 保留所有权利。
Silver nanoparticles (Ag NPs) are becoming increasingly popular as antimicrobial agents in consumer goods with consequent risk to environmental health from discharges. Environmentally relevant fate and transport investigations are limited but essential to gain understanding towards bioavailability and toxicology. In this study, monodisperse 15 nm citrate-stabilised Ag NPs were synthesised, characterised and then fractionated by flow field-flow fractionation (FIFFF) at environmentally relevant conditions (pH 5 or 8, presence of natural organic macromolecules (NOM) and presence of sodium or calcium). At low ionic strength, Ag NPs particle size increased as pH increased from 5 to 8. However, changing the ionic strength from 10(-3) to 10(-2) M Na increased instability of the Ag NPs, and loss of peak at pH 5 but in the presence of humic substance (HS), a reduction in NP size was seen, most likely due to a reduction in the diffuse layer. The presence of Ca2+ ions, at the higher ionic strengths caused complete loss of the solution Ag NPs with or without HS, most likely due to aggregation. At the lower Ca2+ ionic strength the Ag NPs were still unstable, but again, in the presence of HS the NPs were largely dispersed. The presence of HS improved stability of Ag NPs under these conditions by forming a Surface coating resulting in both steric and charge stabilisation. This work implies that Ag NPs could have long residence times in aquatic systems in the presence of HS potentially resulting in increased bioavailability. (C) 2009 Elsevier B.V. All rights reserved.