Heinrich Frank, Ng Tiffany, Vanderah David J, Shekhar Prabhanshu, Mihailescu Mihaela, Nanda Hirsh, Lösche Mathias
Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102, USA.
Langmuir. 2009 Apr 7;25(7):4219-29. doi: 10.1021/la8033275.
Mixed self-assembled monolayers (SAMs) of beta-mercaptoethanol and the new synthetic lipid 1,2-dipalmityl-3-[w-mercaptonona(ethylene oxide)] glycerol (FC 16) were investigated for their ability to form sparsely tethered bilayer lipid membranes (stBLMs) completed with various phospholipids. We investigated the structural and functional properties of FC16-based stBLMs and compared these to stBLMs prepared using a previously characterized synthetic lipid, 1,2-dimyristyl-3-[omega-mercaptohexa(ethylene oxide)] glycerol (WC14). FC16-based stBLMs show increased resistivity to ion transfer and an increase in the submembrane space of approximately 0.5 nm. Importantly, FC16-based stBLMs formed well-defined, complete bilayers with charged phospholipids such as 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG). In these, POPG incorporates into the outer monolayer leaflet in the same ratio as in the immersion solution but is excluded from the inner leaflet. In all cases that we have investigated thus far, the area densities of the lipids within the bilayers were on average close to those in free bilayer membranes. For charged phospholipids, FC16 appears to provide a distinct advantage over WC14 for the formation of well-defined stBLMs.
研究了β-巯基乙醇与新型合成脂质1,2-二棕榈酰基-3-[ω-巯基壬（环氧乙烷）]甘油（FC 16）的混合自组装单分子层（SAMs）形成用各种磷脂完成的稀疏连接双层脂质膜（stBLMs）的能力。我们研究了基于FC16的stBLMs的结构和功能特性，并将其与使用先前表征的合成脂质1,2-二肉豆蔻酰基-3-[ω-巯基六（环氧乙烷）]甘油（WC14）制备的stBLMs进行比较。基于FC16的stBLMs对离子转移的电阻增加，并且膜下空间增加约0.5nm。重要的是，基于FC16的stBLMs与带电荷的磷脂如1-棕榈酰基-2-油酰基-sn-甘油-3-磷酸甘油（POPG）形成明确的完整双层。在这些双层中，POPG以与浸没溶液中相同的比例掺入外层单分子层小叶中，但被排除在内层小叶之外。在我们迄今为止研究的所有情况下，双层内脂质的面积密度平均接近自由双层膜中的密度。对于带电荷的磷脂，FC16在形成明确的stBLMs方面似乎比WC14具有明显优势。
