Institute for Medical Research and Occupational Health, Zagreb, Croatia.
School of Medicine, University of Zagreb, Zagreb, Croatia.
J Appl Toxicol. 2023 Mar;43(3):416-430. doi: 10.1002/jat.4392. Epub 2022 Sep 13.
Silver nanoparticles (AgNPs) show a plethora of possible applications due to their antimicrobial properties. Different coatings of AgNPs are used in order to increase stability, availability, and activity. However, the question about the toxicity after prolonged exposure still remains. Here, we show that different surface coatings affect in vitro toxicity and internalization of AgNPs in porcine kidney (PK15) cells. AgNPs coated with cetyltrimethylammonium bromide (CTAB), poly(vinylpyrrolidone) (PVP), sodium bis(2-ethylhexyl)-sulfosuccinate (AOT), poly-L-lysine (PLL), and bovine serum albumin (BSA) were toxic at the concentration of 10 mg Ag/L and higher. The toxicity increased in the following manner: PVP-AgNPs < CTAB-AgNPs < PLL-AgNPs < AOT-AgNPs < BSA-AgNPs. All types of AgNPs were internalized by the PK15 cells in a dose-dependent manner with greater internalization of AgNPs bearing positive surface charge. Transmission electron microscopy (TEM) experiments showed that AgNPs were located in the lysosomal compartments, while the co-treatment with known inhibitors of endocytosis pathways suggested macropinocytosis as the preferred internalization pathway. When inside the cell, all types of AgNPs induced the formation of reactive oxygen species while decreasing the concentration of the cell's endogenous antioxidant glutathione. The comet assay indicated possible genotoxicity of tested AgNPs starting at the concentration of 2 mg Ag/L or higher, depending on the surface functionalization. This study demonstrates the toxicity of AgNPs pointing to the importance of biosafety evaluation when developing novel AgNPs-containing materials.
银纳米粒子（AgNPs）由于其抗菌特性显示出了大量可能的应用。为了提高稳定性、可用性和活性，AgNPs 采用了不同的涂层。然而，关于长时间暴露后毒性的问题仍然存在。在这里，我们展示了不同的表面涂层会影响 AgNPs 在猪肾（PK15）细胞中的体外毒性和内化。用十六烷基三甲基溴化铵（CTAB）、聚乙烯吡咯烷酮（PVP）、双（2-乙基己基）磺基琥珀酸钠（AOT）、聚-L-赖氨酸（PLL）和牛血清白蛋白（BSA）包覆的 AgNPs 在 10mg Ag/L 及更高浓度下具有毒性。毒性按以下方式增加：PVP-AgNPs<CTAB-AgNPs<PLL-AgNPs<AOT-AgNPs<BSA-AgNPs。所有类型的 AgNPs 都以剂量依赖的方式被 PK15 细胞内化，带正表面电荷的 AgNPs 内化程度更高。透射电子显微镜（TEM）实验表明，AgNPs 位于溶酶体区室中，而内吞作用途径的已知抑制剂的共同处理表明巨胞饮作用是首选的内化途径。当进入细胞内时，所有类型的 AgNPs 都诱导活性氧的形成，同时降低细胞内源性抗氧化剂谷胱甘肽的浓度。彗星试验表明，测试的 AgNPs 从 2mg Ag/L 或更高浓度开始可能具有遗传毒性，这取决于表面功能化。这项研究证明了 AgNPs 的毒性，指出在开发新型含 AgNPs 的材料时进行生物安全性评估的重要性。
