Kuhl T L, Majewski J, Wong J Y, Steinberg S, Leckband D E, Israelachvili J N, Smith G S
Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA.
Biophys J. 1998 Nov;75(5):2352-62. doi: 10.1016/S0006-3495(98)77679-9.
The structure of polymer-decorated phospholipid monolayers at the solid-solution interface was investigated using neutron reflectometry. The monolayers were composed of distearoylphosphatidylethanolamine (DSPE) matrixed with varying amounts of DSPE-PEG (DSPE with polyethylene glycol covalently grafted to its headgroup). Mixed lipid monolayers were Langmuir-Blodgett deposited onto hydrophobic quartz or silicon substrates, previously hydrophobized by chemically grafting a robust monolayer of octadecyltrichlorosilane (OTS). We show that this method results in homogeneous and continuous phospholipid monolayers on the silanated substrates and determine that the grafted PEG chains extend away from the monolayers into the solvent phase as a function of their density, as expected from scaling theories. In addition, ligands were coupled to the end of the PEG chains and selective binding was demonstrated using fluorescence microscopy. Our results demonstrate that these constructs are ideal for further characterization and studies with well-defined monomolecular films.
使用中子反射仪研究了固液界面处聚合物修饰的磷脂单层的结构。这些单层由二硬脂酰磷脂酰乙醇胺（DSPE）基质和不同量的DSPE-PEG（头基共价接枝有聚乙二醇的DSPE）组成。混合脂质单层通过朗缪尔-布洛杰特法沉积在疏水石英或硅基底上，这些基底先前通过化学接枝一层牢固的十八烷基三氯硅烷（OTS）单层而进行了疏水化处理。我们表明，该方法在硅烷化基底上形成了均匀且连续的磷脂单层，并确定接枝的PEG链根据其密度从单层延伸到溶剂相中，这与标度理论预期的一致。此外，将配体偶联到PEG链的末端，并使用荧光显微镜证明了选择性结合。我们的结果表明，这些构建体非常适合用于具有明确单分子膜的进一步表征和研究。
