Polymer-cushioned bilayers. I. A structural study of various preparation methods using neutron reflectometry.
Polymer-cushioned bilayers. I. A structural study of various preparation methods using neutron reflectometry.
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DOI：
10.1016/s0006-3495(99)76992-4
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发表时间：
1999-09
影响因子：
3.4
通讯作者：
J. Wong;J. Majewski;M. Seitz;C. K. Park;J. Israelachvili;G. Smith
中科院分区：
文献类型：
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作者：
J. Wong;J. Majewski;M. Seitz;C. K. Park;J. Israelachvili;G. Smith
中子反射法研究评估了不同方法制备聚合物缓冲脂质双分子层所产生的结构。研究了四种不同的方法将二myristoylphosphatidycholine （DMPC）双层沉积到聚乙烯亚胺（PEI）涂层的石英衬底上：1)囊泡吸附到先前干燥的聚合物层上；2)在裸底物上进行囊泡吸附，然后进行聚合物吸附；3、4)Langmuir-Blodgett脂质单分子层垂直沉积在含有聚合物的亚相上形成聚合物支撑的脂质单分子层，然后通过脂质单分子层水平沉积或4)囊泡吸附形成外脂质单分子层。研究表明，聚合物层的初始条件是成功形成所需结构的关键因素，即在水合PEI层上形成连续的双层。除了水平沉积外，我们所期望的结构在所有研究方法中都被发现。这些聚合物支持的双分子层之间的相互作用力在另一篇论文中进行了研究(Wong， J. Y.， C. K. Park， M. Seitz， J. Israelachvili. 1999。J.77:1458-1468)，这表明聚合物缓冲层的存在显著地改变了相互作用电位。这些聚合物支持的双分子层可以作为模型系统，在更接近真实细胞膜环境的条件下研究跨膜蛋白。
This neutron reflectometry study evaluates the structures resulting from different methods of preparing polymer-cushioned lipid bilayers. Four different techniques to deposit a dimyristoylphosphatidylcholine (DMPC) bilayer onto a polyethylenimine (PEI)-coated quartz substrate were examined: 1) vesicle adsorption onto a previously dried polymer layer; 2) vesicle adsorption onto a bare substrate, followed by polymer adsorption; and 3, 4) Langmuir-Blodgett vertical deposition of a lipid monolayer spread over a polymer-containing subphase to form a polymer-supported lipid monolayer, followed by formation of the outer lipid monolayer by either 3) horizontal deposition of the lipid monolayer or 4) vesicle adsorption. We show that the initial conditions of the polymer layer are a critical factor for the successful formation of our desired structure, i.e., a continuous bilayer atop a hydrated PEI layer. Our desired structure was found for all methods investigated except the horizontal deposition. The interaction forces between these polymer-supported bilayers are investigated in a separate paper (Wong, J. Y., C. K. Park, M. Seitz, and J. Israelachvili. 1999.Biophys. J.77:1458-1468), which indicate that the presence of the polymer cushion significantly alters the interaction potential. These polymer-supported bilayers could serve as model systems for the study of transmembrane proteins under conditions more closely mimicking real cellular membrane environments.