Cunningham Brittany, Engstrom Arek M, Harper Bryan J, Harper Stacey L, Mackiewicz Marilyn R
Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331, USA.
School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, OR 97331, USA.
Nanomaterials (Basel). 2021 Jun 8;11(6):1516. doi: 10.3390/nano11061516.
Silver nanoparticles (AgNPs) are widely used in commerce, however, the effect of their physicochemical properties on toxicity remains debatable because of the confounding presence of Ag ions. Thus, we designed a series of AgNPs that are stable to surface oxidation and Ag ion release. AgNPs were coated with a hybrid lipid membrane comprised of L-phosphatidylcholine (PC), sodium oleate (SOA), and a stoichiometric amount of hexanethiol (HT) to produce oxidant-resistant AgNPs, Ag-SOA-PC-HT. The stability of 7-month aged, 20-100 nm Ag-SOA-PC-HT NPs were assessed using UV-Vis, dynamic light scattering (DLS), and inductively coupled plasma mass spectrometry (ICP-MS), while the toxicity of the nanomaterials was assessed using a well-established, 5-day embryonic zebrafish assay at concentrations ranging from 0-12 mg/L. There was no change in the size of the AgNPs from freshly made samples or 7-month aged samples and minimal Ag ion release (<0.2%) in fishwater (FW) up to seven days. Toxicity studies revealed AgNP size- and concentration-dependent effects. Increased mortality and sublethal morphological abnormalities were observed at higher concentrations with smaller nanoparticle sizes. This study, for the first time, determined the effect of AgNP size on toxicity in the absence of Ag ions as a confounding variable.
银纳米颗粒（AgNPs）在商业中被广泛使用，然而，由于银离子的混杂存在，其物理化学性质对毒性的影响仍存在争议。因此，我们设计了一系列对表面氧化和银离子释放稳定的AgNPs。用由L-磷脂酰胆碱（PC）、油酸钠（SOA）和化学计量的己硫醇（HT）组成的混合脂质膜包覆AgNPs，以制备抗氧化剂的AgNPs，即Ag-SOA-PC-HT。使用紫外可见光谱、动态光散射（DLS）和电感耦合等离子体质谱（ICP-MS）评估7个月老化的20-100 nm Ag-SOA-PC-HT NPs的稳定性，同时使用成熟的5天胚胎斑马鱼试验在0-12 mg/L的浓度范围内评估纳米材料的毒性。新鲜制备的样品或7个月老化的样品中AgNPs的尺寸没有变化，并且在长达7天的鱼水（FW）中银离子释放极少（<0.2%）。毒性研究揭示了AgNP尺寸和浓度依赖性效应。在较高浓度和较小纳米颗粒尺寸下观察到死亡率增加和亚致死形态异常。本研究首次在不存在作为混杂变量的银离子的情况下确定了AgNP尺寸对毒性的影响。
