Silver nanoparticles (Ag NPs) are widely used in consumer products especially because of their antimicrobial properties. However, this wide usage of Ag NPs is accompanied by their release into the environment where they will be rapidly transformed to other silver species – especially silver sulfide (Ag₂S). In the present study, we synthesized Ag NPs and sulfidized them to obtain a core-shell system Ag@Ag₂S NPs. Both types of particles form stable dispersions with hydrodynamic diameters of less than 100 nm when diluted in water, but tend to form micrometer-sized agglomerates in biological exposure media. Application of Ag and Ag@Ag₂S NPs to rainbow trout intestinal cells (RTgutGC) resulted in a concentration-dependent cytotoxicity for both types of particles, as assessed by a three-endpoint assay for metabolic activity, membrane integrity and lysosomal integrity. The Ag NPs were shown to be slightly more toxic than the Ag@Ag₂S NPs. Adding Ag or Ag@Ag₂S NPs to RTgutGC cells, grown on a permeable membrane to mimic the intestinal barrier, revealed considerable accumulation of silver for both types of particles. Indeed, the cells significantly attenuated the NP translocation, allowing only a fraction of the metal to translocate across the intestinal epithelium. These findings support the notion that the intestine constitutes an important sink for Ag NPs and that, despite the reduced cytotoxicity of a sulfidized NP form, the particles can enter fish where they may constitute a long-term source for silver ion release and cytotoxicity.

银纳米粒子 (Ag NPs) 被广泛用于消费品，特别是因为它们的抗菌特性。然而，Ag NPs 的这种广泛使用伴随着它们释放到环境中，在那里它们将迅速转化为其他银物质 - 特别是硫化银 (Ag ₂ S)。在本研究中，我们合成了 Ag NPs 并对其进行硫化以获得核壳系统 Ag@Ag ₂ S NPs。当在水中稀释时，这两种类型的颗粒都会形成流体动力学直径小于 100 nm 的稳定分散体，但在生物暴露介质中往往会形成微米级的团聚体。Ag和Ag@Ag _2的应用S NPs 对虹鳟鱼肠细胞 (RTgutGC) 导致两种类型的颗粒的浓度依赖性细胞毒性，如代谢活性、膜完整性和溶酶体完整性的三终点测定所评估的那样。Ag NPs 的毒性略高于 Ag@Ag ₂ S NPs。添加 Ag 或 Ag@Ag ₂RTgutGC 细胞的 S NPs 在可渗透膜上生长以模拟肠道屏障，显示两种类型的颗粒都有大量的银积累。事实上，细胞显着减弱了 NP 易位，仅允许一小部分金属跨肠上皮易位。这些发现支持了这样的观点，即肠道构成了 Ag NP 的重要汇，尽管硫化 NP 形式的细胞毒性降低，但颗粒可以进入鱼类，在那里它们可能构成银离子释放和细胞毒性的长期来源。