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

自然界经常使用大的生物分子来捕捉和移除混合物中的小目标，就像渔民用网保护鱼一样。但生物分子相对脆弱，这限制了它们的用途，需要能够以高亲和力和选择性捕捉特定靶点的合成模拟物，如有色染料。大分子、超分子和纳米化学研究计划支持圣母大学的布拉德利·史密斯教授合成和研究圆柱形分子，这些分子将染料捕获到小珠子的表面。涂有染料的珠子可以很容易地用廉价的相机甚至肉眼检测到。它们在环境和生物医学应用中具有潜在的应用价值。研究活动为学生提供化学合成和数据分析方面的严格培训，以及在口头和书面陈述方面的丰富经验。作为教学项目的一部分，史密斯教授和他的学生正在升级免费的互联网练习册《有机结构说明》，包括一系列问题的视频答案。免费和不受限制地访问视频答案可以帮助那些无法获得高级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基础上，即添加了聚乙二醇链的水溶性方酸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穿线。术语Synthavidin(合成亲和素)是该主/客关联系统的通用名称。这项研究开发了基础的合成和超分子化学，以产生强大和快速的捕获水中的高荧光方酸染料，并络合诱导吸收和荧光性质的变化。这项工作产生了分子设计概念，引导超分子研究人员转向在水中操作的高亲和力受体。珠粒捕获法具有两个强大的特性，即能够从混浊介质中去除酶裂解的荧光染料，以及由于珠子周围的超支化荧光壳的自组装而产生放大的信号。该试验设计具有通用性，可以扩展到包括多种类型的裂解酶。

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.