Wang Haixia, Shang Li, Maffre Pauline, Hohmann Siegfried, Kirschhöfer Frank, Brenner-Weiß Gerald, Nienhaus Gerd Ulrich
Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), Wolfgang-Gaede-Strasse 1, 76131, Karlsruhe, Germany.
Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76344, Eggenstein-Leopoldshafen, Germany.
Small. 2016 Nov;12(42):5836-5844. doi: 10.1002/smll.201602283. Epub 2016 Sep 8.
Biological responses of cells and organisms to nanoparticle exposure crucially depend on the properties of the protein adsorption layer ("protein corona") forming on nanoparticle surfaces and their characterization is a crucial step toward a deep, mechanistic understanding of their build-up. Previously, adsorption of one type of model protein on nanoparticles was systematically studied in situ by using fluorescence correlation spectroscopy. Here, the first such study of interactions is presented between water-solubilized CdSe/ZnS quantum dots (QDs) and a complex biofluid, human blood serum. Despite the large number of proteins in serum, a protein layer of well-defined (average) thickness forming on QD surfaces is observed. Both the thickness and the apparent binding affinity depend on the type of QD surface ligand. Kinetic experiments reveal that the protein corona formed from serum is irreversibly bound, whereas the one formed from human serum albumin was earlier observed to be reversible. By using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and mass spectrometry, the most abundant serum proteins contributing to the formation of a hard corona on the QDs are identified.
细胞和生物体对纳米颗粒暴露的生物学反应关键取决于在纳米颗粒表面形成的蛋白质吸附层（“蛋白质冠”）的性质，对其进行表征是深入、从机制上理解其形成过程的关键一步。此前，通过荧光相关光谱法对一种模型蛋白在纳米颗粒上的吸附进行了原位系统研究。本文首次展示了水溶性CdSe/ZnS量子点（QD）与复杂生物流体人血清之间相互作用的此类研究。尽管血清中有大量蛋白质，但在量子点表面观察到形成了具有明确（平均）厚度的蛋白质层。厚度和表观结合亲和力都取决于量子点表面配体的类型。动力学实验表明，由血清形成的蛋白质冠是不可逆结合的，而由人血清白蛋白形成的蛋白质冠早些时候被观察到是可逆的。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳和质谱法，确定了对量子点上硬冠形成有贡献的最丰富的血清蛋白。
