Holmberg Maria, Hou Xiaolin
Department of Micro- and Nanotechnology and, Risø National Laboratory for Sustainable Energy, Technical University of Denmark, Frederiksborgvej 399, DK-4000 Roskilde, Denmark.
Langmuir. 2009 Feb 17;25(4):2081-9. doi: 10.1021/la8031978.
In this study, competitive adsorption of albumin and IgG (immunoglobulin G) from human serum solutions and protein mixtures onto polymer surfaces is studied by means of radioactive labeling. By using two different radiolabels (125I and 131I), albumin and IgG adsorption to polymer surfaces is monitored simultaneously and the influence from the presence of other human serum proteins on albumin and IgG adsorption, as well as their mutual influence during adsorption processes, is investigated. Exploring protein adsorption by combining analysis of competitive adsorption from complex solutions of high concentration with investigation of single protein adsorption and interdependent adsorption between two specific proteins enables us to map protein adsorption sequences during competitive protein adsorption. Our study shows that proteins can adsorb in a multilayer fashion onto the polymer surfaces and that the outcome of IgG adsorption is much more sensitive to surface characteristics than the outcome of albumin adsorption. Using high concentrations of protein solution and hydrophobic polymer surfaces during adsorption can induce IgG aggregation, which is observed as extremely high IgG adsorptions. Besides using a more hydrophilic substrate, surface-induced IgG aggregation can be inhibited by changing the adsorption sequence of albumin and IgG.
在本研究中，通过放射性标记的方法研究了人血清溶液和蛋白质混合物中白蛋白和免疫球蛋白G（IgG）在聚合物表面的竞争性吸附。使用两种不同的放射性标记（125I和131I），同时监测白蛋白和IgG在聚合物表面的吸附情况，并研究其他人体血清蛋白的存在对白蛋白和IgG吸附的影响，以及它们在吸附过程中的相互影响。通过结合高浓度复杂溶液中竞争性吸附分析、单一蛋白质吸附研究以及两种特定蛋白质之间的相互依存吸附研究来探索蛋白质吸附，使我们能够描绘竞争性蛋白质吸附过程中的蛋白质吸附顺序。我们的研究表明，蛋白质可以以多层方式吸附到聚合物表面，并且IgG吸附的结果比白蛋白吸附的结果对表面特性更为敏感。在吸附过程中使用高浓度蛋白质溶液和疏水性聚合物表面会诱导IgG聚集，这表现为极高的IgG吸附量。除了使用更亲水的底物外，改变白蛋白和IgG的吸附顺序可以抑制表面诱导的IgG聚集。
