Institute for Advanced Material, Jiangsu University, Zhenjiang 212013, China.
Nanoscale. 2018 Nov 8;10(43):20162-20170. doi: 10.1039/c8nr04207a.
The interaction of two-dimensional (2D) nanomaterials and bacterial membranes has attracted tremendous attention in antibacterial applications. Various peculiarities of 2D nanomaterials may lead to multiple mechanisms of their interactions with membranes. Here, we investigated the interaction between molybdenum disulfide (MoS2) nanosheets and the bacterial membrane by using both theoretical and experimental approaches. Molecular dynamics simulation presented that MoS2 nanosheets can disrupt the structure of the lipid membrane by making dents on its surface and extracting phospholipid molecules to reduce the integrity of the membrane. This is attributed to the combination of the dispersion interaction of lipid tails with S atoms and the electrostatic interactions of lipid head groups with the Mo and S atoms in the lateral edges of the MoS2 nanosheet. Scanning electron microscopy and transmission electron microscopy confirmed the dents and the destruction of the cell membrane, which would lead to the loss of cytoplasm and the death of bacteria. It should be noted that the phenomenon where MoS2 induces a dent is different from the direct insertion of graphene-based nanomaterials, which might be due to the thicker and stiffer structure of MoS2. Therefore, we believe that the molecular interactions of 2D nanomaterials with bacterial membranes should be highly correlated with their structural characteristics. This newly discovered mechanism of MoS2 nanomaterials to disrupt the cell membrane may promote the application of transition metal dichalcogenide (TMD) nanomaterials in designing remarkable antibacterial materials in the near future.
二维（2D）纳米材料与细菌膜的相互作用在抗菌应用中引起了极大的关注。2D 纳米材料的各种特性可能导致它们与膜相互作用的多种机制。在这里，我们通过理论和实验方法研究了二硫化钼（MoS2）纳米片与细菌膜的相互作用。分子动力学模拟表明，MoS2 纳米片可以通过在其表面制造凹痕并提取磷脂分子来破坏脂质膜的结构，从而降低膜的完整性。这归因于脂质尾部与 S 原子的色散相互作用以及脂质头部基团与 MoS2 纳米片横向边缘的 Mo 和 S 原子的静电相互作用的结合。扫描电子显微镜和透射电子显微镜证实了凹痕和细胞膜的破坏，这将导致细胞质的损失和细菌的死亡。值得注意的是，MoS2 诱导凹痕的现象与基于石墨烯的纳米材料的直接插入不同，这可能是由于 MoS2 更厚和更硬的结构。因此，我们认为 2D 纳米材料与细菌膜的分子相互作用应该与其结构特征高度相关。这种 MoS2 纳米材料破坏细胞膜的新发现机制可能会促进过渡金属二硫属化物（TMD）纳米材料在不久的将来设计出色的抗菌材料中的应用。
