Collaborative Research: Leveraging the interactions between carbon nanomaterials and DNA molecules for mitigating antibiotic resistance

抗药性细菌(超级细菌)被认为是21世纪人类面临的最大挑战之一。在美国，每年有超过23,000人死于抗生素耐药细菌，每年大约花费550亿美元来对抗抗生素耐药性。抗生素耐药细菌的传播引起了全球的关注，人们担心我们可能会回到抗生素出现之前的时代。对抗生素的耐药性是由细菌的遗传物质携带的，这种遗传物质称为抗生素耐药性基因。这些新出现的污染物正在污水处理厂等已建成的环境中迅速传播。最近的研究正在探索使用新的方法和材料，如碳纳米材料，来消除抗生素耐药性基因的可行性。尽管潜力巨大，但由于缺乏对抗生素耐药基因和碳纳米材料之间相互作用的深入了解，以前的研究一直报告去除效率低下。这个项目的目标是了解抗生素耐药基因与碳纳米材料相互作用时的基本化学。基于从该项目获得的知识，可以开发出一种强大的碳纳米材料-膜系统，并将其应用于污水处理厂，以对抗抗生素耐药性。预计该系统还将广泛适用于各种新出现的污染物的处理，这些污染物很难用传统技术去除。除了推进工程应用和基础化学，这个项目还将为高积极性、低收入的高中生提供教育机会。来自STEM传统上代表性不足的群体的本科生也将参与这项研究。这种早期接触研究有望在拓宽参与学生的视野和学术/职业目标方面产生变革性的影响。抗菌素抗性基因被认为是一种新兴的污染物，可以在城市污水处理厂等建成环境中迅速传播。利用碳纳米材料吸附和降解抗生素耐药基因是对抗抗生素耐药性的一种有前途的方法。然而，由于它们的纳米级性质对吸附和降解的影响还没有被很好地了解，所以在文献中一直没有有效去除的报道。这个项目的目标是从机理上理解抗生素耐药基因和碳纳米材料之间的相互作用。这一目标将通过三个相互关联的目标来实现：1)了解与涂有还原氧化石墨烯的膜之间的相互作用；2)增强抗生素耐药基因在改性膜上的静电吸附；3)加强改性膜对抗生素耐药基因的电化学降解。通过将碳纳米材料固定在膜上，这种相互作用有望通过压力驱动的过滤得到很容易的调节和增强。此外，膜可以作为碳纳米材料带电的支撑层，允许在阳极电位下进行静电吸附，以及在阴极电位下进行活性氧物种诱导的降解。电势的变化也将导致协同作用。该项目预计将为水和废水应用的纳米结构材料和异质纳米系统的设计提供洞察力。该项目制定的“捕集和清除”战略(即先吸附后降解)预计将适用于处理非均质环境中新出现的污染物。该项目的一个主要好处将是满足社会对缓解日益增长的水和废水处理能源需求的需求。该项目将通过支持高中生、本科生和研究生的研究来促进教学、培训和学习。主要调查人员一直并将继续与女性工程师协会、全国黑人工程师协会和西班牙裔专业工程师协会密切合作，邀请来自STEM传统上代表性不足的群体的学生参与研究。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。

Antibiotic resistant bacteria ("superbugs") are considered one of the greatest challenges facing humanity in the 21st century. In the U.S., more than 23,000 deaths per year are associated with antibiotic resistant bacteria, and approximately $55 billion is spent annually to combat antibiotic resistance. The spread of antibiotic resistant bacteria is causing global concern that we may be returning to a pre-antibiotic era. Resistance to antibiotics is carried by the genetic materials of bacteria called antibiotic resistance genes. These emerging contaminants are being rapidly transmitted in built environments such as wastewater treatment plants. Recent studies are exploring the feasibility of using new approaches and materials, such as carbon nanomaterials, to remove antibiotic resistance genes. Despite the great potential, previous studies consistently report inefficient removal due to a lack of in-depth understanding of the interactions between antibiotic resistance genes and carbon nanomaterials. The goal of this project is to understand the fundamental chemistry when antibiotic resistance genes interact with carbon nanomaterials. Based on the knowledge gained from this project, a robust carbon nanomaterial-membrane system can be developed and applied to wastewater treatment plants to combat antibiotic resistance. The system is also expected to be broadly applicable to the treatment of various emerging contaminants that are difficult to remove using conventional technologies. In addition to advancing engineering applications and fundamental chemistry, this project will provide educational opportunities for highly motivated, low-income high school students. Undergraduate students from groups traditionally under-represented in STEM will also be involved in the research. This early exposure to research is expected to be transformative in broadening the horizons and academic/career goals of participating students.Antibiotic resistance genes are considered an emerging contaminant and can spread rapidly in the built environment such as municipal wastewater treatment plants. One of the promising approaches to combat antibiotic resistance is the use of carbon nanomaterials to adsorb and degrade antibiotic resistance genes. However, because the effects of their nanoscale properties on adsorption and degradation are not well understood, inefficient removal is consistently reported in the literature. The goal of this project is to develop a mechanistic understanding of the interactions between antibiotic resistance genes and carbon nanomaterials. This goal will be achieved by pursuing three interrelated objectives: 1) understand the interactions with membranes coated with reduced graphene oxide; 2) enhance the electrostatic adsorption of antibiotic resistance genes on the modified membranes; and 3) enhance the electrochemical degradation of antibiotic resistance genes by the modified membranes. By immobilizing carbon nanomaterials on membranes, the interactions are expected to be readily tuned and enhanced with pressure-driven filtration. In addition, the membranes can act as a support layer for carbon nanomaterials to be electrically charged, allowing electrostatic adsorption at anodic potentials as well as reactive oxygen species-induced degradation at cathodic potentials. Alternation of the electrical potential will also result in synergistic interactions. This project is expected to provide insight into the design of nanostructured materials and heterogeneous nanosystems for water and wastewater applications. The "trap-and-zap" strategy (i.e., adsorption followed by degradation) developed in this project is expected to be applicable to the treatment of emerging contaminants in heterogeneous environments. A major benefit of this project will be addressing the societal need for alleviating the ever-growing energy demand for water and wastewater treatment. This project will promote teaching, training, and learning by supporting \high school, undergraduate, and graduate students in research. The principal investigators have been and will continue working closely with the Society of Women Engineers, the National Society of Black Engineers, and the Society of Hispanic Professional Engineers to engage students from groups traditionally under-represented in STEM in research.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.