Collaborative Research: Characterization and Optimization of N-Heterocyclic Carbene Functionalized Nanoparticle Systems

在化学学部的大分子、超分子和纳米化学项目的支持下，田纳西大学的David Jenkins博士和dr。圣母大学的Jon Camden和Gina Navoa Svarovsky探索了n -杂环碳烯（NHCs）化学在金纳米颗粒表面改性中的应用。金纳米颗粒通常由带电分子（如柠檬酸盐或带有硫醇锚定基团的单层）稳定，广泛用于化学、生物和环境技术，但由于纳米颗粒在水中固有的不稳定性，其使用受到限制。Drs。Jenkins和Camden正在寻找通过使用NHC配体来克服这一限制的方法。为了做到这一点，他们使用了一种自上而下的方法，包括这些配体在转移到金纳米颗粒表面之前的初始协调，以创造金属离子。他们正在使用各种表征工具来评估这种化学反应，并更好地了解是什么NHC配体促进了功能化金纳米颗粒的稳定性。Drs。詹金斯、卡姆登和斯瓦洛夫斯基正在进行一个教学研究员驻留项目，在研究实验室中创造身临其境的研究体验，以及一个学生参与真实科学（SEAS）项目，让中学生参与原始科学数据。该研究包括金属NHC配合物的合成、表征和转移到金纳米颗粒表面，表征NHC配体库在金纳米颗粒上的键合和紧密排列，以及随后对NHC功能化金的稳定性和寿命的评估。所有这些研究都采用自上而下的方法，其中金纳米颗粒在分离的硬币金属NHC配合物在溶液中形成后被功能化。这种普遍的、自上而下的策略有望广泛适用于不同形状和大小的金纳米颗粒。这种方法有可能克服与自下而上的功能化步骤相关的限制，其中每个单独的反应通常针对特定系统进行优化。杂环碳烯功能化的金纳米颗粒有望克服传统表面化学所面临的挑战。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Macromolecular, Supramolecular, and Nanochemistry Program in the Division of Chemistry, Dr. David Jenkins of the University of Tennessee and Drs. Jon Camden and Gina Navoa Svarovsky of the University of Notre Dame explore the use of N-heterocyclic carbenes (NHCs) chemistry for the surface modification of gold nanoparticles. Gold nanoparticles, which are typically stabilized by charged molecules such as citrate or monolayers with thiol anchoring groups, are used in wide-ranging chemical, biological, and environmental technologies but use is limited by the inherent instability of the nanoparticles in water. Drs. Jenkins and Camden are identifying ways to overcome this limitation by using NHC ligands. To do so, they are using a top-down method that involves the initial coordination of these ligands to coinage metal ions before being transferred to gold nanoparticle surfaces. They are using a variety of characterization tools to evaluate this chemistry and to better understand what NHC ligands promote enhanced stability of the functionalized gold nanoparticles. Drs. Jenkins, Camden, and Svarovsky are pursuing a Teaching Fellows Residency program to create an immersive research experience in the research laboratories and a Student Engagement in Authentic Science (SEAS) program that engages middle school students with original scientific data.The research involves the synthesis, characterization, and transfer of metal NHC complexes to gold nanoparticle surfaces, the characterization of the resulting bonding and close packing of a library of NHC ligands on gold nanoparticles, and the subsequent evaluation of NHC-functionalized gold stability and longevity. All of these studies utilize a top-down approach wherein the gold nanoparticles are functionalized after isolated coinage metal NHC complexes have formed in solution. This universal, top-down strategy is expected to be broadly applicable to gold nanoparticles of varying shapes and sizes. This approach has the potential to overcome limitations associated with bottom-up functionalization steps where each individual reaction is typically optimized for a specific system. Gold nanoparticles functionalized with heterocyclic carbenes hold promise in the quest to overcome challenges faced by conventional surface chemistries.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.