Effect of the Surface Hydrophilicity on the Formation of a Membrane-type Interface: Study Using an Acoustic Wave Device
Effect of the Surface Hydrophilicity on the Formation of a Membrane-type Interface: Study Using an Acoustic Wave Device
复制标题
表面亲水性对膜型界面形成的影响：使用声波装置的研究
作者：
K. Melzak;E. Ralph;E. Gizeli
利用声波装置研究了脂质囊泡在不同亲水性固体表面的沉积。该装置在103 MHz下工作，由石英衬底和用作声波导的聚合物覆盖层以及金薄层组成。通过用十六烷基硫醇（HDT）改性金表面16 h和用巯基十一烷醇（MUO）改性金表面10 min和16 h来控制装置表面的亲水性，以分别获得疏水、相对亲水和亲水表面。通过真实的时间记录声波的相位和振幅来监测PBS中的2-油酰棕榈酰-sn-甘油基-3-磷酸胆碱（POPC）的囊泡悬浮液与每个表面的相互作用。在疏水性（HDT）和亲水性（16 h MUO）表面上检测到的声信号分别表明形成了支持的单层和双层，而在亲水性较低（10 min MUO）表面上检测到囊泡层。通过使用14C标记的脂质并通过监测BSA在每个表面上的非特异性结合来证实上述发现。这些实验清楚地表明，固体表面的亲水性对于设计二维（双层）或三维（囊泡）膜型界面层是非常重要的。此外，同时监测的相位和振幅的声波被证明提供补充信息的质量和粘弹性界面的变化。
An acoustic wave device was used to study the deposition of lipid vesicles on solid surfaces of different hydrophilicity. The device operated at 103 MHz and consisted of a quartz substrate with a polymer overlayer acting as an acoustic waveguide and a thin layer of gold. The hydrophilicity of the device surface was controlled by modifying the gold surface with hexadecanethiol (HDT) for 16 h and mercaptoundecanol (MUO) for 10 min and 16 h in order to obtain a hydrophobic, relatively hydrophilic, and hydrophilic surface, respectively. The interaction of a vesicle suspension of 2-oleoylpalmitoyl-sn-glycero-3-phosphocholine (POPC) in PBS with each surface was monitored by recording the phase and amplitude of the acoustic wave in real time. The acoustic signal detected on the hydrophobic (HDT) and hydrophilic (16 h MUO) surfaces indicated the formation of a supported monolayer and bilayer, respectively, while a vesicle layer was detected on the less hydrophilic (10 min MUO) surface. The above findings were confirmed by using 14 C-labeled lipids and by monitoring the nonspecific binding of BSA on each surface. These experiments clearly showed that the hydrophilic properties of the solid surface are very important for designing a two dimensionsional (bilayer) or three-dimensional (vesicle) membrane-type interface layer. Furthermore, the simultaneous monitoring of the phase and amplitude of the acoustic wave was shown to provide complementary information related to mass and viscoelastic interfacial changes.