WestCHEM/Department of Pure & Applied Chemistry , University of Strathclyde , 295 Cathedral Street , Glasgow G1 1XL , U.K.
Advanced Science Research Center (ASRC) of Graduate Center and Department of Physics in City College of New York , CUNY , New York , New York 10031 , United States.
ACS Appl Mater Interfaces. 2018 Nov 14;10(45):39353-39362. doi: 10.1021/acsami.8b13793. Epub 2018 Oct 30.
Proteins represent complex biomolecules capable of wide-ranging but also highly specific functionalities. Their immobilization on material supports can enable broad applications from sensing and industrial biocatalysis to biomedical interfaces and materials. We demonstrate the advantages of using aqueous-processed cross-linked polyphenol coatings for immobilizing proteins, including IgG, avidin, and various single and multidomain enzymes on diverse materials, to enable active biofunctional structures (e.g., ca. 2.2, 1.7, 1.1, and 4.8 mg·m active phosphatase on nanoporous cellulose and alumina, steel mesh, and polyester fabric, respectively). Enzyme assays, X-ray photoelectron spectroscopy, silver staining, supplemented with contact angle, solid-state C NMR, HPLC, and ESI-MS measurements were used to characterize the polyphenols, coatings, and protein layers. We show that the functionalization process may be advantageously optimized directly for protein activity rather than the traditional focus on the thickness of the coating layer. Higher activities (by more than an order of magnitude in some cases) and wider process pH and material compatibility are demonstrated with polyphenol coatings than other approaches such as polydopamine. Coatings formed from different plant polyphenol extracts, even at lowered purity (and cost), were also found to be highly functional. Chemically, our results indicate that polyphenol coatings differ from polydopamine mainly because of the elimination of amine groups, and that polyphenol layers with intermediate levels of reactivity may better lead to high immobilized protein activity. Overall, an improved understanding of simple-to-use polyphenol coatings has been obtained, which enabled a significant development in active protein surfaces that may be applied across diverse materials and nanostructured supports.
蛋白质是具有广泛但又高度特异性功能的复杂生物分子。将其固定在材料载体上，可以在从传感和工业生物催化到生物医学界面和材料等广泛领域中得到应用。我们展示了使用水相处理的交联多酚涂层固定蛋白质（包括 IgG、亲和素和各种单结构域和多结构域酶）的优势，这些蛋白质固定在不同的材料上，形成了具有活性的生物功能结构（例如，在纳米多孔纤维素和氧化铝、钢网和聚酯纤维上分别有约 2.2、1.7、1.1 和 4.8 mg·m 的活性磷酸酶）。通过酶测定、X 射线光电子能谱、银染，辅以接触角、固态 C NMR、HPLC 和 ESI-MS 测量，对多酚、涂层和蛋白质层进行了表征。我们表明，功能化过程可以直接针对蛋白质活性进行优化，而不是传统上关注涂层的厚度。与其他方法（如聚多巴胺）相比，多酚涂层具有更高的活性（在某些情况下提高了一个数量级以上）和更宽的 pH 范围和材料兼容性。即使多酚提取物的纯度（和成本）降低，不同植物多酚提取物形成的涂层也具有高度的功能性。从化学角度来看，我们的结果表明，多酚涂层与聚多巴胺的主要区别在于胺基的消除，并且具有中等反应性的多酚层可能更有利于实现高固定化蛋白质活性。总的来说，我们对简单易用的多酚涂层有了更好的理解，这使得具有活性的蛋白质表面得到了显著的发展，可以应用于各种材料和纳米结构的载体。
