Unité de chimie des interfaces, Institut de la matière condensée et des nanosciences, Université catholique de Louvain, Croix du Sud 2/18, 1348 Louvain-la-Neuve, Belgium.
Colloids Surf B Biointerfaces. 2010 Jun 1;77(2):139-49. doi: 10.1016/j.colsurfb.2010.01.014. Epub 2010 Jan 29.
In order to evaluate the respective influence of surface nanotopography and chemical composition on blood compatibility, plasma protein adsorption (fibrinogen - Fg and albumin - HSA, quantified simultaneously by dual radioassays) and platelet adhesion were investigated on a range of materials. Reference surfaces were glass, polystyrene and poly(vinyl chloride), as well as pieces of commercial blood bags. Colloidal lithography with 65 and 470 nm polystyrene latex particles was used to prepare nanostructured surfaces with either one layer of colloids or with bimodal roughness. The surfaces were further conditioned by adsorption of poly(ethylene oxide) (PEO)-containing compounds (Pluronic F 68 and PLL-g-PEG). Study of the simultaneous adsorption of Fg and HSA on reference substrates demonstrated that the Fg/HSA adsorbed amount ratio decreases as the substrate hydrophobicity increases, the lower ratio being obtained with commercial blood bag. This is due to the higher resistance of HSA adsorbed on hydrophobic substrates to displacement by proteins from the solution. Such higher resistance was also shown to occur in the case of displacement by constituents of non-diluted blood plasma. Nanostructured substrates gave about the same Fg/HSA ratio as polystyrene and poly(vinyl chloride). Surface conditioning with Pluronic F 68 reduced the adsorption of Fg in competition with HSA on all substrates except glass, while PLL-g-PEG decreased the adsorbed amount of both Fg and HSA on glass but not on the other substrates. Positive correlations between the amount of adhering blood platelets and both the Fg/HSA ratio and the absolute amount of Fg adsorbed in competition with HSA were found for all substrates (reference and nanostructured, as such or after PEO conditioning, except native glass which had to be discarded due to the formation of clots in the liquid phase). These quantities were also related to the state of activation of adhering platelets. This supports the concept that blood compatibility of materials is primarily governed by the presence of Fg in the adsorbed phase, as a result of the competition with other plasma proteins. This is in turn strongly influenced by surface hydrophobicity. Surface nanostructuration as performed here (relief in the range of 50-500 nm) did not affect significantly the relationship between Fg adsorption and platelet adhesion.
为了评估表面纳米形貌和化学成分对血液相容性的各自影响，通过双重放射免疫测定法同时定量测定血浆蛋白吸附（纤维蛋白原-Fg 和白蛋白-HSA）和血小板黏附，研究了一系列材料。参考表面为玻璃、聚苯乙烯和聚氯乙烯，以及商业血袋的碎片。使用胶体光刻技术，用 65nm 和 470nm 的聚苯乙烯乳胶粒子制备具有单层胶体或双模态粗糙度的纳米结构表面。进一步通过吸附含有聚氧化乙烯（PEO）的化合物（Pluronic F 68 和 PLL-g-PEG）对表面进行处理。研究 Fg 和 HSA 在参考基底上的同时吸附表明，随着基底疏水性的增加，Fg/HSA 吸附量的比值降低，商业血袋获得的比值最低。这是由于疏水性基底上吸附的 HSA 更难被溶液中的蛋白质取代。这种更高的阻力也发生在非稀释血浆成分取代的情况下。纳米结构基底与聚苯乙烯和聚氯乙烯的 Fg/HSA 比值大致相同。Pluronic F 68 表面处理减少了除玻璃外所有基底上 Fg 在与 HSA 竞争中的吸附，而 PLL-g-PEG 减少了玻璃上 Fg 和 HSA 的吸附量，但对其他基底没有影响。所有基底（参考和纳米结构基底，原样或经过 PEO 处理后，除了由于在液相中形成凝块而必须丢弃的天然玻璃外）均发现附着血小板的数量与 Fg/HSA 比值以及与在与 HSA 竞争中吸附的 Fg 的绝对量之间存在正相关。这些量还与附着血小板的激活状态有关。这支持了这样的概念，即材料的血液相容性主要由吸附相中 Fg 的存在决定，这是由于与其他血浆蛋白的竞争所致。这反过来又受到表面疏水性的强烈影响。这里进行的表面纳米结构化（在 50-500nm 的范围内进行）并没有显著影响 Fg 吸附与血小板黏附之间的关系。
