Department of Physics, School of Natural Sciences, Shiv Nadar University, NH-91, Tehsil Dadri, G. B. Nagar, Uttar Pradesh, 201314, India.
Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, Bidhannagar, Kolkata, 700064, India.
Chem Phys Lipids. 2018 Sep;215:1-10. doi: 10.1016/j.chemphyslip.2018.06.001. Epub 2018 Jun 23.
Ionic liquids (ILs) have generated considerable attention recently because of their cytotoxicity and application as antibiotics. However, the mechanism of how they damage cell membranes is not currently well understood. In this paper, the antibacterial activities of two imidazolium-based ILs, namely 1-butyl- 3-methylimidazolium tetrafluroborate ([BMIM][BF4]) and 1-ethyl- 3-methylimidazolium tetrafluroborate ([EMIM][BF4]) have been investigated. The activity of [BMIM][BF4] on gram negative bacteria E. coli is observed to be stronger compared with the short chained [EMIM][BF4]. To explain this observation, the effects of these ILs on the self-assembled structures of model cellular membranes have been investigated. The in-plane elasticity of a monolayer formed at air-water interface by 1,2-dipalmitoyl- sn-glycero- 3-phosphocholine (DPPC) lipids was reduced in the presence of the ILs. The x-ray reflectivity studies on polymer supported lipid bilayer have shown the bilayer to shrink and correspondingly exhibit an increase in electron density. The presence of a certain mol% of negatively charged lipid, 1,2-dipalmitoyl-rac-glycero-3-phospho-L-serine (DPPS), in DPPC mono- and bi-layers enhances the effect considerably.
离子液体（ILs）由于其细胞毒性和作为抗生素的应用而引起了相当大的关注。然而，它们破坏细胞膜的机制目前还不是很清楚。本文研究了两种基于咪唑的离子液体，即 1-丁基-3-甲基咪唑四氟硼酸盐([BMIM][BF4])和 1-乙基-3-甲基咪唑四氟硼酸盐([EMIM][BF4])的抗菌活性。与短链的[EMIM][BF4]相比，[BMIM][BF4]对革兰氏阴性菌大肠杆菌的活性更强。为了解释这一观察结果，研究了这些离子液体对模型细胞膜自组装结构的影响。在存在离子液体的情况下，在气-水界面形成的由 1,2-二棕榈酰基-sn-甘油-3-磷酸胆碱（DPPC）脂质组成的单层的面内弹性降低。X 射线反射研究表明聚合物支撑的脂质双层收缩，相应地电子密度增加。在 DPPC 单双层中存在一定摩尔%的带负电荷的脂质 1,2-二棕榈酰基-rac-甘油-3-磷酸-L-丝氨酸（DPPS），会显著增强这种效应。
