Homogeneous hybrid droplet interface bilayers assembled from binary mixtures of DPhPC phospholipids and PB-b-PEO diblock copolymers
Homogeneous hybrid droplet interface bilayers assembled from binary mixtures of DPhPC phospholipids and PB-b-PEO diblock copolymers
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DOI：
10.1016/j.bbamem.2022.183997
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发表时间：
2022-10-01
影响因子：
3.4
通讯作者：
Sarles，Stephen A.
中科院分区：
文献类型：
--
作者：
Koner，Subhadeep;Tawfik，Joseph;Sarles，Stephen A.
由磷脂和两亲嵌段共聚物构建的杂化膜寻求利用这两种成分的优势来构建具有改进性能的仿生界面。然而，杂化膜尚未形成或使用液滴界面双层（DIB）方法进行研究，这种方法为揭示膜结构和力学的纳米级变化提供了优势，并为组装高阶组织提供了途径。我们报道了合成二植烷酰磷脂酰胆碱（DPhPC）脂和低分子量1,2聚丁二烯-b-聚乙烯氧化物（PBPEO）两亲嵌段共聚物的二元混合物在十六烷中形成的杂化液滴界面双层（hDIBs），并使用电生理测量和成像来评估PBPEO在膜中的作用。这项工作表明，含有高达15 mol% PBPEO和DPhPC的hdib是脂质和聚合物的均匀混合物，具有高度的离子传输抗性，并且稳定-包括在外加电压下。此外，它们具有与仅dphpc双层相似的疏水厚度，但膜张力值也明显较低。这些特性与液滴之间的粘附能量降低以及在显著较低的阈值电压下alamethicin离子通道的形成相吻合，表明即使脂质双分子层中含有适量的两亲性嵌段共聚物，也为调节仿生膜的物理性质提供了一条途径。
Hybrid membranes built from phospholipids and amphiphilic block copolymers seek to capitalize on the benefits of both constituents for constructing biomimetic interfaces with improved performance. However, hybrid membranes have not been formed or studied using the droplet interface bilayer (DIB) method, an approach that offers advantages for revealing nanoscale changes in membrane structure and mechanics and offers a path toward assembling higher-order tissues. We report onhybriddroplet interface bilayers (hDIBs) formed in hexadecane from binary mixtures of synthetic diphytanoyl phosphatidylcholine (DPhPC) lipids and low molecular weight 1,2 polybutadiene-b-polyethylene oxide (PBPEO) amphiphilic block copolymers and use electrophysiology measurements and imaging to assess the effects of PBPEO in the membrane. This work reveals that hDIBs containing up to 15 mol% PBPEO plus DPhPC are homogeneously mixtures of lipids and polymers, remain highly resistive to ion transport, and are stable—including under applied voltage. Moreover, they exhibit hydrophobic thicknesses similar to DPhPC-only bilayers, but also have significantly lower values of membrane tension. These characteristics coincide with reduced energy of adhesion between droplets and the formation of alamethicin ion channels at significantly lower threshold voltages, demonstrating that even moderate amounts of amphiphilic block copolymers in a lipid bilayer provide a route for tuning the physical properties of a biomimetic membrane.