Ewins Eleanor, Lira Rafael B, Zhang Weiyi, Yuan Jiayin, Antonietti Markus, Robinson Tom, Dimova Rumiana
Department of Theory & Bio-Systems Max Planck Institute of Colloids and Interfaces Science Park Golm 14424 Potsdam Germany.
Department of Colloid Chemistry Max Planck Institute of Colloids and Interfaces Science Park Golm 14424 Potsdam Germany.
Adv Sci (Weinh). 2018 Dec 17;6(4):1801602. doi: 10.1002/advs.201801602. eCollection 2019 Feb 20.
Polymer-based nanoparticles have an increasing presence in research due to their attractive properties, such as flexible surface functionality design and the ability to scale up production. Poly(ionic liquid) (PIL) nanoparticles of size below 50 nm are very unique in terms of their high charge density and internal onion-like morphology. The interaction between PIL nanoparticles and giant unilamellar vesicles (GUVs) of various surface charge densities is investigated. GUVs represent a convenient model system as they mimic the size and curvature of plasma membranes, while simultaneously offering direct visualization of the membrane response under the microscope. Incubating PIL nanoparticles with GUVs results in poration of the lipid membrane in a concentration- and charge-dependent manner. A critical poration concentration of PILs is located and the interactions are found to be analogous to those of antimicrobial peptides. Microbial mimetic membranes are already affected at submicromolar PIL concentrations where contrast loss is observed due to sugar exchange across the membrane, while at high concentrations the collapse of vesicles is observed. Finally, a confocal microscopy-based approach assessing the particle permeation through the membrane is reported and a mechanism based on bilayer frustration and pore stabilization via particle integration in the membrane is proposed.
基于聚合物的纳米颗粒因其具有吸引力的特性，如灵活的表面功能设计和扩大生产规模的能力，在研究中的应用越来越广泛。尺寸小于50 nm的聚离子液体（PIL）纳米颗粒在高电荷密度和内部洋葱状形态方面非常独特。研究了PIL纳米颗粒与各种表面电荷密度的巨型单层囊泡（GUV）之间的相互作用。GUV是一种方便的模型系统，因为它们模拟了质膜的大小和曲率，同时在显微镜下能直接观察到膜的反应。将PIL纳米颗粒与GUV一起孵育会导致脂质膜以浓度和电荷依赖的方式形成孔洞。确定了PIL的临界穿孔浓度，发现其相互作用与抗菌肽的相互作用类似。微生物模拟膜在亚微摩尔浓度的PIL下就已受到影响，此时由于糖跨膜交换导致对比度丧失，而在高浓度下则观察到囊泡的塌陷。最后，报道了一种基于共聚焦显微镜的方法来评估颗粒通过膜的渗透情况，并提出了一种基于双层受挫和通过颗粒整合到膜中实现孔稳定的机制。
