Collaborative Research: Cyclodextrin-Based 2D Materials for the Treatment of Legacy and Emerging Perfluoroalkyl Substances

全氟烷基和多氟烷基物质（PFASs）在供水中的存在对环境和人类健康构成威胁。标准的水净化方法通常对PFAS去除无效。这项研究将探索一种潜在的变革性方法，以设计环境相容的吸附剂来去除PFAS，研究活动将直接推动对选择性去除饮用水源中PFAS的材料的发现和基本理解。 佛罗里达国际大学和北卡罗来纳州州立大学之间的这项研究合作将通过汇集由本科生，研究生，博士后研究助理和来自不同州的两个机构的研究人员组成的研究团队来促进教学，培训和学习。该项目将通过多学科研究经验，参加科学研讨会，专业发展和参与外联活动，为代表性不足的学生提供一个宝贵的环境。项目成果将通过同行评审的出版物、在科学会议上的介绍以及特别介绍和研讨会广泛传播。此外，还计划举办一系列网络研讨会，以提高公众对PFAS健康风险的认识，并向供水商传授去除PFAS的有效方法，以保护人类健康，并帮助确保国家的供水安全。该研究的总体目标是探索环境友好的氨基β-环糊精（am-beta-CD）和氧化石墨烯基材料的组合，用于修复传统和新兴的PFAS。氧化石墨烯将与官能化环糊精（CD）连接，用于修复传统的PFAS和新兴的全氟烷基醚酸，如GenX和短链PFAS。 初步结果表明，β-环糊精（β-CD）可以很容易地包裹各种PFAS，其缔合常数高达10^5 M^-1，导致溶液中95%的PFAS发生络合。虽然该团队已经证明了使用β-CD与活性炭结合可以增强全氟辛酸（PFOA）的去除，但对PFAS的CD络合以及如何利用CD：PFAS络合物特性进行修复缺乏基本了解。这种知识差距阻碍了PFAS监测和水处理系统的优化。 这项研究将测试以下假设：am-beta-CD：PFAS复合物将在环境相关条件下持续存在，使得基于am-beta-CD的氧化石墨烯吸附剂可用于PFAS修复。在强有力的初步证据和集合研究人员的广泛经验的指导下，该小组将追求两个具体目标：（1）确定am-beta-CD：PFAS复合物的结合常数和详细表征;（2）采用am-beta-CD连接的石墨烯氧化物基质修复PFAS。清除短链和新出现的PFAS将是最优先考虑的事项。该研究将有助于对PFASs和CD分子间相互作用的基本理解，以及CD基二维纳米吸附剂的实用性。该项目有望为PFAS补救措施的可持续战略发展提供关键信息。该奖项反映了NSF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。

The presence of per- and polyfluoroalkyl substances (PFASs) in water supplies is a threat to environmental and human health. Standard water purification methods are generally ineffective for PFAS removal. This research will explore a potentially transformative approach to engineering environmentally compatible adsorbents for PFAS removal, and the research activities will directly advance discovery and fundamental understanding of materials that selectively remove PFASs from drinking water sources. This research collaboration between Florida International University and North Carolina State University will promote teaching, training, and learning by bringing together a research team composed of undergraduate students, graduate students, a postdoctoral research associate, and researchers from two institutions in different states. This project will provide a valuable environment for underrepresented students through multidisciplinary research experiences, participation in scientific workshops, professional development, and engagement in outreach activities. Project results will be broadly disseminated through peer-reviewed publications, presentations at scientific meetings, and special presentations and seminars. Additional a web seminar series is planned to enhance the public awareness of the health risks of PFASs and educate water suppliers on effective methodologies for PFAS removal to protect human health and help secure the Nation's water supply. The overall objective of the research is to explore the combination of environmentally friendly amino beta-cyclodextrins (am-beta-CDs) and graphene oxide-based materials for the remediation of legacy and emerging PFASs. Graphene oxide will be linked to functionalized cyclodextrins (CDs) for the remediation of legacy PFASs and emerging perfluoroalkylether acids, such as GenX, and short-chain PFASs. Preliminary results show that beta-cyclodextrin (beta-CD) readily encapsulates a variety of PFASs with association constants up to 10^5 M^-1, resulting in complexation of up to 95% of PFAS in solution. While the team has demonstrated enhanced removal of perfluoro octanoic acid (PFOA) using beta-CD in combination with activated carbon, there is a lack in the fundamental understanding about the CD complexation of PFASs and how the CD:PFAS complex properties may be exploited for remediation. This knowledge gap prevents the optimization of these systems for PFAS monitoring and water treatment. This research will test the hypothesis that am-beta-CD:PFAS complexes will persist in environmentally relevant conditions such that am-beta-CD-based graphene oxide adsorbents can be utilized for PFAS remediation. Guided by strong preliminary evidence and the extensive experience of the assembled researchers, the group will pursue two specific objectives: (1) Determination of binding constants for and detailed characterization of am-beta-CD:PFAS complexes; and (2) employ am-beta-CD-attached graphene-oxide matrices for remediation of PFASs. Removal of short-chain and emerging PFASs will be the highest priority. The study will contribute to the fundamental understanding of the molecular interactions of PFASs and CDs and the utility of CD-based two-dimensional nano-adsorbents. The project is expected to provide information critical for the development of sustainable strategies for PFAS remediation.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.