We herein report the preparation of a surface that behaves in a hydrophobic manner but does not undergo protein adsorption in an aqueous/organic two-phase system. We found that polyethylene-glycol (PEG)-modified poly(dimethylsiloxane) (PDMS) exhibits hydrophobic properties when the surface is immersed in an organic solution, while the PEG moiety prevents protein adsorption on the PDMS surface in an aqueous solution at high protein concentrations due to the dynamic behaviour of the PEG moiety. As such, we demonstrated the in-well droplet formation of an aqueous solution containing a high protein concentration. In addition, to demonstrate the feasibility of this method in single cell analyses, a droplet array of a liquid medium containing 10% fetal bovine serum and HeLa cells was formed. The preparation of a droplet array using our PDMS-PEG surface to promote in-well droplet formation avoided the use of flow control equipment and complicated microstructures. We therefore expect that the dynamic wettability of our reported surface will be applicable in single cell and biochemical analyses, such as protein characterisation using crystallography or immunoassays.

中文翻译：

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在水/有机两相体系中，聚乙二醇改性的聚（二甲基硅氧烷）表面的动态润湿性†

我们在本文中报道了制备表面的方法，该表面表现为疏水性但在水/有机两相系统中不经历蛋白质吸附。我们发现当表面浸入有机溶液中时，聚乙二醇（PEG）改性的聚（二甲基硅氧烷）（PDMS）表现出疏水性，而PEG部分阻止了蛋白质在高蛋白质浓度的水溶液中吸附在PDMS表面上的蛋白质由于PEG部分的动态行为。这样，我们证明了含有高蛋白质浓度的水溶液的孔内液滴形成。另外，为了证明该方法在单细胞分析中的可行性，形成了包含10％胎牛血清和HeLa细胞的液体培养基的液滴阵列。使用我们的PDMS-PEG表面来促进孔内液滴形成的液滴阵列的制备避免了使用流量控制设备和复杂的微结构。因此，我们希望我们报道的表面的动态可湿性将适用于单细胞和生化分析，例如使用晶体学或免疫测定法进行蛋白质表征。