CAREER: Ribosome-inspired Synthesis of Precision Polymers

大自然用分子装配线制造非常大的分子(所谓的聚合物)。这些装配线对生命至关重要，它们以特定的顺序一个接一个地为不断增长的聚合物链添加构建块。这就是DNA和RNA的形成方式。在这个项目中，施奈贝利博士正在模仿自然流水线的方法，创造出定义明确的聚合物材料。虽然这项研究的重点是启用和理解人工分子装配线，但创建的定义明确的聚合物最终可能是各种重要应用的有用材料。人造分子装配线是通过将催化剂与带环的聚合物连接起来创建的，这些环沿着不断增长的链滑动。这种催化剂为不断增长的聚合物逐一添加了单独的积木。此外，施尼贝利博士还通过在当地一家科学博物馆(佛蒙特州伯灵顿的艾克湖水族馆和科学中心)和当地高中的K-12推广活动，让公众参与到聚合物化学中来。为了实现这一目标，施尼贝利博士发明了互动动态模型。这些模型引导K-12年级的学生独立地发现聚合物生长的关键方面，并在未来的STEM工作队伍中培养独立的创造性思维。在化学系化学催化计划的支持下，佛蒙特州大学的Schnebeli博士正在学习如何启用新的聚合机制，最终可能导致序列定义的、圆周率共轭聚合物的分子装配线。施奈贝利博士受到自然创造序列定义的功能性大分子的启发，正在创造特殊的互锁催化剂，这种催化剂可以将难以控制的步骤聚合转化为强大的活生生的链增长过程。虽然许多共轭、环状和超支化单体都存在高效的链增长过程，但这项研究探索了一种通用的一般单体的链增长策略，其中许多单体还不能以可控的方式聚合。Schnebeli博士的设计防止了催化剂从聚合物上脱落，从而使这种新的活性聚合方法完全无链转移。施奈贝利博士正在利用这种新的聚合技术，以类似于核糖体构建蛋白质的方式，实现DNA模板的无酶转化为各种pi共轭的精密聚合物。为了支持该项目的更广泛影响，Schnebeli博士正在积极参与K-12项目的推广工作，建立特殊的宏观动态模型。这些模型旨在引导K-12学生发现不同聚合机制的定性和定量方面，以在未来的STEM工作人员中培养基于发现的推理和创造性思维。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Nature builds very large molecules (so called polymers) with molecular assembly lines. Crucial for life, these assembly lines add building blocks to growing polymer chains one after another in a specific order. This is how DNA and RNA are formed. In this project, Dr. Schneebeli is imitating the natural assembly-line approach to create well-defined polymeric materials. While this research focuses on enabling and understanding artificial molecular assembly lines, the well-defined polymers created may ultimately be useful materials for a variety of important applications. The artificial molecular assembly lines are created by connecting a catalyst to the polymers with rings that slide along the growing chains. This catalyst adds individual building blocks to the growing polymers one by one. In addition, Dr. Schneebeli is engaging the public in polymer chemistry through K-12 outreach at a local science museum (ECHO Lake Aquarium and Science Center in Burlington, VT) and at local high schools. For this outreach, Dr. Schneebeli is inventing interactive dynamic models. These models lead K-12 students to discover key aspects of polymer growth independently and foster independent creative thinking within the future STEM workforce.With support from the Chemical Catalysis Program of the Chemistry Division, Dr. Schneebeli of the University of Vermont is learning how to enable new polymerization mechanisms that could ultimately result in molecular assembly lines for sequence-defined, pi-conjugated polymers. Inspired by how Nature creates sequence-defined, functional macromolecules, Dr. Schneebeli is creating special interlocked catalysts, which can transform difficult-to-control step polymerizations into robust living chain-growth processes. While efficient chain-growth processes exist for numerous conjugated, cyclic, and hyperbranching monomers, this research explores a universal chain-growth strategy for general monomers, many of which cannot yet be polymerized in a controlled manner. Dr. Schneebeli's design prevents the catalysts from falling off the polymers, thus rendering this new living polymerization methodology fully chain-transfer free. Dr. Schneebeli is utilizing this new polymerization technique to enable the enzyme-free translation of DNA templates into diverse, pi-conjugated precision polymers, in a manner analogous to how the ribosome builds proteins. In support of the broader impacts of the project, Dr. Schneebeli is actively engaged in K-12 outreach with special macroscopic dynamic models. These models are devised to lead K-12 students to discover qualitative and quantitative aspects of different polymerization mechanisms to foster discovery-based reasoning and creative thinking among the future STEM workforce.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.