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

抗生素抗性细菌（“超级细菌”）被认为是人类在21世纪世纪面临的最大挑战之一。在美国，每年有23 000多例死亡与抗生素耐药性细菌有关，每年用于防治抗生素耐药性的费用约为550亿美元。抗生素耐药性细菌的传播正在引起全球关注，我们可能会回到前抗生素时代。对抗生素的抗性是由细菌的遗传物质携带的，称为抗生素抗性基因。这些新出现的污染物在污水处理厂等建筑环境中迅速传播。最近的研究正在探索使用新方法和材料（如碳纳米材料）去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抗性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效率低下。该项目的目标是了解抗生素抗性基因与碳纳米材料相互作用时的基本化学。基于从该项目中获得的知识，可以开发一种强大的碳纳米材料膜系统，并将其应用于废水处理厂，以对抗抗生素耐药性。预计该系统还将广泛适用于处理各种难以使用传统技术去除的新兴污染物。除了推进工程应用和基础化学之外，该项目还将为积极性高的低收入高中生提供教育机会。来自传统上在STEM中代表性不足的群体的本科生也将参与这项研究。这种早期的研究接触预计将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。抗生素耐药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筑环境中迅速传播。对抗抗生素耐药性的一种有前途的方法是使用碳纳米材料吸附和降解抗生素耐药性基因。然而，由于它们的纳米级性质对吸附和降解的影响还没有很好地理解，文献中一致报道了低效的去除。该项目的目标是对抗生素抗性基因和碳纳米材料之间的相互作用进行机械理解。这一目标将通过追求三个相互关联的目标来实现：1）理解与涂覆有还原氧化石墨烯的膜的相互作用; 2）增强抗生素抗性基因在改性膜上的静电吸附;以及3）增强改性膜对抗生素抗性基因的电化学降解。通过将碳纳米材料固定在膜上，预计这种相互作用将很容易通过压力驱动过滤进行调整和增强。此外，该膜可以作为碳纳米材料带电的支撑层，允许在阳极电位下的静电吸附以及在阴极电位下的活性氧诱导的降解。电势的交替也将导致协同相互作用。该项目有望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见解。“陷阱和打击”策略（即，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水和废水处理日益增长的能源需求的需求。 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。主要研究人员已经并将继续与女性工程师协会，黑人工程师全国协会和西班牙裔专业工程师协会密切合作，让传统上在STEM中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，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

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.