Synthetic Mimics of Avidin/Biotin for In-Situ Capture Applications

大自然经常使用大的生物分子从混合物中捕获和去除小的目标，这与渔民使用网捕获鱼的概念相同。但是生物分子是相对脆弱的，这限制了它们的用途，并且需要合成模拟物来捕获具有高亲和力和选择性的特定目标，例如有色染料。大分子、超分子和纳米化学项目支持圣母大学的Bradley Smith教授合成和研究在小珠子表面捕获染料的圆柱形分子。这种涂有染料的珠子可以很容易地用便宜的相机甚至肉眼检测到。它们在环境和生物医学应用方面具有潜在的用途。这些研究活动为学生提供了化学合成和数据分析方面的严格训练，以及口头和书面报告方面的丰富经验。作为教学项目的一部分，史密斯教授和他的学生们正在升级免费的网络练习册《有机结构阐释》，包括一系列问题的视频答案。免费和无限制地访问视频答案可以帮助那些缺乏先进教育资源或经验丰富的教师的学生。该项目建立在最近的一项发现的基础上，即带有附加聚乙二醇链的水溶性方卡因染料可以通过含有蒽侧壁的水溶性四内酰胺大环以极高的亲和力进行螺纹连接。术语Synthavidin（合成亲和素）是这个主/客关联系统的通用名称。该研究发展了潜在的合成和超分子化学，以产生强而快速的高荧光方英染料在水中的捕获，以及络合诱导的吸收和荧光性质的变化。这项工作产生了分子设计概念，指导超分子研究人员在水中操作的高亲和力受体。珠捕获试验具有两个强大的特性，即从浑浊介质中去除酶裂解荧光染料的能力，以及由于珠周围的超支化荧光壳的自组装而产生的放大信号。分析设计是通用的，可以扩展到包括许多类型的切割酶。

Nature often uses large biomolecules to capture and remove small targets from a mixture, in the same conceptual way that a fisherman employs a net to secure a fish. But biomolecules are relatively fragile which limits their utility, and there is a need for synthetic mimics that can capture specific targets, such as colored dyes, with high affinity and selectivity. The Macromolecular, Supramolecular and Nanochemistry Program supports Professor Bradley Smith of the University of Notre Dame to synthesize and study cylinder-shaped molecules that capture dyes on the surface of small beads. The dye coated beads can be easily detected using a cheap camera or even the naked eye. They are potentially useful in environmental and biomedical applications. The research activities provide rigorous student training in chemical synthesis and data analysis, as well as extensive experience in oral and written presentations. As part of a pedagogical project, Professor Smith and his students are upgrading the free internet workbook Organic Structure Elucidation by including a series of video answers to the problems. Free and unrestricted access to the video answers helps students who lack access to advanced educational resources or experienced instructors.The project builds on a recent discovery that water soluble squaraine dyes with appended polyethylene glycol chains can be threaded with extremely high affinity by a water soluble tetralactam macrocycle containing anthracene side-walls. The term Synthavidin (synthetic avidin) is the generic name for this host/guest association system. The research develops the underlying synthetic and supramolecular chemistry to produce strong and rapid capture of highly fluorescent squaraine dyes in water, and complexation-induced changes in absorption and fluorescence properties. The work produces molecular design concepts that guide supramolecular researchers towards high affinity receptors for operation in water. The bead capture assay is endowed with two powerful attributes, namely, the capability to remove enzyme cleaved fluorescent dye from turbid media and the creation of amplified signal due to self-assembly of a hyperbranched fluorescent shell around the bead. The assay design is generalizable and can be expanded to include many types of cleavage enzymes.