Berglin Mattias, Pinori Emiliano, Sellborn Anders, Andersson Marcus, Hulander Mats, Elwing Hans
Department of Cell and Molecular Biology, Interface Biophysics, Göteborg University, and Department of Surgery, Sahlgrenska University Hospital, Göteborg SE-40530, Sweden.
Langmuir. 2009 May 19;25(10):5602-8. doi: 10.1021/la803686m.
By combining quartz crystal microbalance with dissipation monitoring (QCM-D) and surface plasmon resonance (SPR), the organic mass, water content, and corresponding protein film structure of fibrinogen adsorbed to acrylic polymeric substrates with varying polymer chain flexibility was investigated. Albumin and immunoglobulin G were included as reference proteins. For fibrinogen, the QCM-D model resulted in decreased adsorbed mass with increased polymer chain flexibility. This stands in contrast to the SPR model, in which the adsorbed mass increased with increased polymer chain flexibility. As the QCM-D model includes the hydrodynamically coupled water, we propose that on the nonflexible polymer significant protein conformational change with water incorporation in the protein film takes place. Fibrinogen maintained a more native conformation on the flexible polymer, probably due to polymer chain rearrangement rather than protein conformational change. In comparison with immunoglobulin G and albumin, polymer chain flexibility had only minor impact on adsorbed mass and protein structure. Understanding the adsorption and corresponding conformational change of a protein together with the mutual rearrangement of the polymer chain upon adsorption not only has implications in biomaterial science but could also increase the efficacy of molecular imprinted polymers (MIPs).
通过结合石英晶体微天平与耗散监测（QCM-D）以及表面等离子体共振（SPR），研究了吸附在具有不同聚合物链柔性的丙烯酸类聚合物基底上的纤维蛋白原的有机质量、含水量及相应的蛋白质膜结构。白蛋白和免疫球蛋白G作为参考蛋白质。对于纤维蛋白原，QCM-D模型显示随着聚合物链柔性增加，吸附质量降低。这与SPR模型相反，在SPR模型中吸附质量随聚合物链柔性增加而增加。由于QCM-D模型包含流体动力学耦合水，我们提出在刚性聚合物上，蛋白质膜中随着水的掺入发生了显著的蛋白质构象变化。纤维蛋白原在柔性聚合物上保持更天然的构象，这可能是由于聚合物链重排而非蛋白质构象变化。与免疫球蛋白G和白蛋白相比，聚合物链柔性对吸附质量和蛋白质结构的影响较小。了解蛋白质的吸附及相应的构象变化以及吸附时聚合物链的相互重排不仅对生物材料科学有意义，还可能提高分子印迹聚合物（MIP）的功效。
