Breznan Dalibor, Nazemof Nazila, Kunc Filip, Hill Myriam, Vladisavljevic Djordje, Gomes James, Johnston Linda J, Vincent Renaud, Kumarathasan Prem
Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
Analyst. 2020 Jul 21;145(14):4867-4879. doi: 10.1039/d0an00380h. Epub 2020 May 29.
Silica nanoparticles (SiNPs) are used in a wide range of consumer products, engineering and medical applications, with likelihood of human exposure and potential health concerns. It is essential to generate toxicity information on SiNP forms and associated physicochemical determinants to conduct risk assessment on these new materials. To address this knowledge gap, we screened a panel of custom synthesized, well-characterized amorphous SiNPs pristine and surface-modified (-C3-COOH, -C11-COOH, -NH, -PEG) of 5 different sizes: (15, 30, 50, 75, 100 nm) for their oxidative potential using an acellular assay. The assay is based on oxidation of dithiothreitol (DTT) by reactive oxygen species and can serve as a surrogate test for oxidative stress. These materials were characterized for size distribution, aggregation, crystallinity, surface area, surface modification, surface charge and metal content. Tests for association between oxidative potential of SiNPs and their physicochemical properties were carried out using analysis of variance and correlation analyses. These test results suggest that the size of amorphous SiNPs influenced their oxidative potential irrespective of the surface modification, with 15 nm exhibiting relatively higher oxidative potential compared to the other sizes. Furthermore, SiNP surface area, surface modification and agglomeration in solution also appeared to affect oxidative potential of these SiNPs. These findings indicate that physicochemical properties are critical in influencing the oxidative behaviour of amorphous SiNPs, with potential to trigger cellular oxidative stress and thus toxicity, when exposed. This information advances our understanding of potential toxicities of these amorphous SiNPs and supports risk assessment efforts and the design of safer forms of silica nanomaterials.
二氧化硅纳米颗粒（SiNPs）被广泛应用于各类消费品、工程和医学领域，人类有接触它们的可能性，也存在潜在的健康问题。生成关于SiNP形态及其相关物理化学决定因素的毒性信息对于对这些新材料进行风险评估至关重要。为了填补这一知识空白，我们使用无细胞试验筛选了一组定制合成、特征明确的5种不同尺寸（15、30、50、75、100纳米）的原始和表面改性（-C3-COOH、-C11-COOH、-NH、-PEG）的无定形SiNPs的氧化潜力。该试验基于活性氧对二硫苏糖醇（DTT）的氧化作用，可作为氧化应激的替代试验。对这些材料的尺寸分布、聚集、结晶度、表面积、表面改性、表面电荷和金属含量进行了表征。使用方差分析和相关性分析对SiNPs的氧化潜力与其物理化学性质之间的关联进行了测试。这些测试结果表明，无定形SiNPs的尺寸影响其氧化潜力，无论表面改性如何，15纳米的SiNPs相比其他尺寸表现出相对较高的氧化潜力。此外，SiNP的表面积、表面改性和在溶液中的团聚似乎也会影响这些SiNPs的氧化潜力。这些发现表明，物理化学性质对于影响无定形SiNPs的氧化行为至关重要，当暴露时有可能引发细胞氧化应激并进而导致毒性。这些信息增进了我们对这些无定形SiNPs潜在毒性的理解，并支持风险评估工作以及更安全形式的二氧化硅纳米材料的设计。
