Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
Colloids Surf B Biointerfaces. 2023 Apr;224:113211. doi: 10.1016/j.colsurfb.2023.113211. Epub 2023 Feb 20.
Nanoplastics (NPs) are mainly generated from the decomposition of plastic waste and industrial production, which have attracted much attention due to the potential risk for humans. The ability of NPs to penetrate different biological barriers has been proved, but the understanding of molecular details is very limited, especially for organic pollutant-NP combinations. Here, we investigated the uptake process of polystyrene NPs (PSNPs) combined with benzo(a)pyrene (BAP) molecules by dipalmitoylphosphatidylcholine (DPPC) bilayers by molecular dynamics (MD) simulations. The results showed that the PSNPs can adsorb and accumulate BAP molecules in water phase and then carried BAP molecules to enter DPPC bilayers. At the same time, the adsorbed BAP promoted the penetration of PSNPs into DPPC bilayers effectively by hydrophobic effect. The process of BAP-PSNP combinations penetrating into DPPC bilayers can be summarized into four steps including adhesion on the DPPC bilayer surface, uptake by the DPPC bilayer, BAP molecules detached from the PSNPs, and the PSNPs depolymerized in the bilayer interior. Furthermore, the amount of adsorbed BAP on PSNPs affected the properties of DPPC bilayers directly, especially the fluidity of DPPC bilayers that determine the physiologic function. Obviously, the combined effect of PSNPs and BAP enhanced the cytotoxicity. This work not only presented a vivid transmembrane process of BAP-PSNP combinations and revealed the nature of the effects of adsorbed benzo(a)pyrene on the dynamic behavior of polystyrene nanoplastics through phospholipid membrane, but also provide some necessary information of the potential damage for organic pollutant-nanoplastic combinations on human health at a molecular level.
纳米塑料（NPs）主要来源于塑料废弃物的分解和工业生产，由于其对人类潜在的风险而受到广泛关注。已经证明 NPs 能够穿透不同的生物屏障，但对分子细节的理解非常有限，特别是对于有机污染物-NP 组合。在这里，我们通过分子动力学（MD）模拟研究了聚苯乙烯 NPs（PSNPs）与苯并[a]芘（BAP）分子结合物被二棕榈酰磷脂酰胆碱（DPPC）双层吸收的过程。结果表明，PSNPs 可以在水相中吸附和积累 BAP 分子，然后携带 BAP 分子进入 DPPC 双层。同时，吸附的 BAP 通过疏水作用有效地促进 PSNPs 进入 DPPC 双层。BAP-PSNP 组合穿透 DPPC 双层的过程可以概括为四个步骤，包括在 DPPC 双层表面的粘附、DPPC 双层的摄取、BAP 分子从 PSNPs 上的脱离以及 PSNPs 在双层内部的解聚。此外，吸附在 PSNPs 上的 BAP 量直接影响 DPPC 双层的性质，特别是 DPPC 双层的流动性，这决定了其生理功能。显然，PSNPs 和 BAP 的联合作用增强了细胞毒性。这项工作不仅呈现了 BAP-PSNP 组合的生动跨膜过程，还通过磷脂膜揭示了吸附苯并[a]芘对聚苯乙烯纳米塑料动态行为的影响性质，为有机污染物-纳米塑料组合对人类健康的潜在危害提供了一些必要的分子水平上的信息。
