Interfacial properties and membrane protein solubilization activity of a series of partially fluorinated octyl-phosphocholine (PC) surfactants were investigated from the viewpoint of the fluorination degree of the hydrophobic chain. The critical micelle concentration (CMC), surface tension lowering activity, molecular occupied area at the CMC and free energy changes of micellization as well as adsorption to the air-water interface for each PC surfactant were estimated from surface tension measurements at 25 °C. The PCs with higher degree of fluorination exhibited low CMC and high surface activity, while the single trifluoromethyl group at the end of the chain appeared to enhance the hydrophilicity of the surfactant molecule. Under conditions where conventional short-chain surfactants, n-octyl-β-D-glucoside, Triton X-100 and dioctanoylphosphatidylcholine significantly solubilize purple membranes (PM), none of the fluorinated-PCs solubilized PM. This suggests that fluorinated-PCs are low-invasive enough to maintain the structure of lipids/protein assemblies like PM.

中文翻译：

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部分氟化辛基-磷酸胆碱表面活性剂的氟化度对其界面性质的影响以及与紫色膜相互作用的膜蛋白模型的影响。

从疏水链的氟化程度出发，研究了一系列部分氟化的辛基-磷酸胆碱（PC）表面活性剂的界面性质和膜蛋白溶解活性。临界胶束浓度（CMC），降低表面张力的活性，CMC处的分子占据面积和胶束化的自由能变化以及每种PC表面活性剂对空气-水界面的吸附是根据25°C下的表面张力测量值估算的。氟化度较高的PC表现出较低的CMC和较高的表面活性，而链末端的单个三氟甲基似乎增强了表面活性剂分子的亲水性。在常规短链表面活性剂正辛基-β-D-葡萄糖苷的条件下，Triton X-100和二辛酰基磷脂酰胆碱可显着溶解紫色膜（PM），而氟化PC均不能溶解PM。这表明氟化PC具有低侵入性，足以维持脂质/蛋白质组件（如PM）的结构。