Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom.
Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT) , 76344 Eggenstein-Leopoldshafen, Germany.
ACS Nano. 2017 Feb 28;11(2):1613-1625. doi: 10.1021/acsnano.6b07352. Epub 2017 Feb 14.
Supported phospholipid membrane patches stabilized on graphene surfaces have shown potential in sensor device functionalization, including biosensors and biocatalysis. Lipid dip-pen nanolithography (L-DPN) is a method useful in generating supported membrane structures that maintain lipid functionality, such as exhibiting specific interactions with protein molecules. Here, we have integrated L-DPN, atomic force microscopy, and coarse-grained molecular dynamics simulation methods to characterize the molecular properties of supported lipid membranes (SLMs) on graphene and graphene oxide supports. We observed substantial differences in the topologies of the stabilized lipid structures depending on the nature of the surface (polar graphene oxide vs nonpolar graphene). Furthermore, the addition of water to SLM systems resulted in large-scale reorganization of the lipid structures, with measurable effects on lipid lateral mobility within the supported membranes. We also observed reduced lipid ordering within the supported structures relative to free-standing lipid bilayers, attributed to the strong hydrophobic interactions between the lipids and support. Together, our results provide insight into the molecular effects of graphene and graphene oxide surfaces on lipid bilayer membranes. This will be important in the design of these surfaces for applications such as biosensor devices.
在传感器器件功能化方面，支持磷脂膜片稳定在石墨烯表面上已经显示出了潜力，包括生物传感器和生物催化。脂质笔式纳米光刻（L-DPN）是一种有用的方法，可用于生成维持脂质功能的支撑膜结构，例如表现出与蛋白质分子的特异性相互作用。在这里，我们整合了 L-DPN、原子力显微镜和粗粒度分子动力学模拟方法，以表征石墨烯和氧化石墨烯支撑物上支撑脂质膜（SLM）的分子特性。我们观察到，稳定脂质结构的拓扑结构因表面性质（极性氧化石墨烯与非极性石墨烯）而异。此外，向 SLM 系统中添加水会导致脂质结构的大规模重组，这对支撑膜内脂质的横向流动性产生可测量的影响。我们还观察到，与自由双层脂质相比，支撑结构内的脂质有序性降低，这归因于脂质和支撑之间的强疏水性相互作用。总之，我们的结果提供了关于石墨烯和氧化石墨烯表面对脂质双层膜的分子影响的见解。这对于这些表面在生物传感器设备等应用中的设计非常重要。
