Interactions between engineered nanoparticles in aquatic systems: Roles of engineered capping agents and natural organic matter

水生系统中工程纳米颗粒之间的相互作用：工程封端剂和天然有机物的作用

• 批准号: 1067794
• 负责人: Jeffrey Nason
• 金额: $ 30.45万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-15 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1067794&HistoricalAwards=false
• 关键词: Interactions; between; engineered; nanoparticles; aquatic

1067794NasonThe rapid development of novel nanomaterials and their incorporation into consumer products has not been paralleled with an equal effort investigating the possible environmental implications. Increasingly, the properties of engineered nanoparticles (ENPs) are tailored for specific applications through the use of organic capping agents. The properties imparted by the capping agents are also likely to influence the transport, toxicity and fate of these materials in the environment. In addition to the purposeful tailoring of ENPs, it is well established that natural organic matter (NOM), which is ubiquitous in surface water, will interact with natural colloids and ENPs, influencing their environmental behavior. To date, little research has focused on systematically investigating the roles that engineered capping agents play in controlling the environmental behavior of ENPs. Although preliminary studies have focused on the interactions between NOM and ENPs, many questions remain about the mechanisms controlling these interactions. Furthermore, none of the existing efforts have attempted to correlate environmental behavior and mechanisms of NOM-ENP interactions with the properties of the ENPs, NOM, and aqueous chemical composition. With the staggering number of new products being developed, it is essential that a fundamental framework be developed for predicting environmental behavior based on these properties. Intellectual Merit: The overarching objective of this work is to develop an improved understanding of the roles of synthetic capping agents and NOM in controlling the homogeneous and heterogeneous aggregation of ENPs in aquatic environmental systems. Using a suite of ligand-stabilized gold nanoparticles (AuNPs) and various NOM isolates, the specific aims of the project are to: (1) Correlate the physicochemical properties of capping agents with interactions between capped ENPs in aquatic systems; (2) Correlate the physicochemical properties of capping agents and NOM with interactions between capped ENPs and NOM in aquatic systems; and (3) Correlate the physicochemical properties of capping agents, NOM and suspended particulate matter with the interactions between capped ENPs and suspended particulates in aquatic systems. ENP stability with respect to homo-aggregation will be assessed using the zeta potential and aggregation rates measured using time-resolved dynamic light scattering. NOM-AuNP interactions will be probed using fluorescence and surface enhanced Raman spectroscopy. Finally, the interactions between AuNPs and suspended colloids will be quantified through a novel application of instrumental neutron activation analysis. By using a group of well-characterized ENPs that vary only with respect to their surface functionality, environmental behavior can be correlated with ENP properties in structure-activity type relationships. This work will provide an improved ability to predict environmental fate based on NP characteristics and yield the feedback necessary for the design of safer nanomaterials. Broader Impacts: The proposed work is transformational in that it aims to move the field away from assessing the environmental implications of nanomaterials on a case-by-case basis and towards the development of structure-activity type relationships correlating environmental behavior with nanoparticle characteristics. It is anticipated that such a framework will be extendable to other classes of nanoparticles and environmental processes like deposition, redox and dissolution. The larger body of work made possible by the project, both by this team and others, will likely facilitate the development of improved models for predicting environmental fate and assessing risk. The work supports the aims of the Safer Nanomaterials and Nanomanufacturing Initiative, of which the PI is a member, and will spur collaborations with colleagues at OSU and other institutions. Other broader impacts will result from the formation of human capital from the education of a Ph.D. student in environmental engineering. Outreach, undergraduate education and opportunities for undergraduate research will be an integral part of the proposed work. The PI has a history of supporting undergraduate research through existing programs at OSU that focus on the recruitment of women and minority students. The PI will continue to mentor undergraduate researchers through hosting senior project teams, Johnson scholars (college freshmen) and SESEY (high school) students in the laboratory. These students will become an integral part of the research team on the work in question. In addition, the PI will develop an educational module focused on particle filtration for water treatment that is appropriate for K-12 and freshmen engineering students as a tool for engaging students in the field of environmental engineering.

1067794 Nason新型纳米材料的快速发展及其在消费品中的应用并没有得到同等的努力来研究可能的环境影响。越来越多的工程纳米颗粒（ENPs）的性能是通过使用有机封端剂为特定应用定制的。封端剂赋予的性质也可能影响这些材料在环境中的运输、毒性和归宿。除了有目的地定制ENPs之外，已经确定的是，地表水中普遍存在的天然有机物（NOM）将与天然胶体和ENPs相互作用，影响其环境行为。迄今为止，很少有研究集中在系统地调查工程封端剂在控制ENPs的环境行为中发挥的作用。虽然初步的研究集中在NOM和ENPs之间的相互作用，许多问题仍然是关于控制这些相互作用的机制。此外，没有一个现有的努力试图将环境行为和NOM-ENP相互作用的机制与ENPs、NOM和水性化学组合物的性质相关联。随着新产品的开发数量惊人，开发一个基于这些特性预测环境行为的基本框架至关重要。智力优势：这项工作的总体目标是开发一个更好的理解的作用，合成封端剂和NOM在控制均匀和异质聚集的ENPs在水环境系统中。利用一系列配体稳定的金纳米颗粒（AuNPs）和各种NOM分离物，本项目的具体目标是：（1）将封端剂的物理化学性质与水生系统中封端的ENPs之间的相互作用相关联;（2）将封端剂和NOM的物理化学性质与水生系统中封端的ENPs和NOM之间的相互作用相关联;（3）将封端剂、NOM和悬浮颗粒物的物理化学性质与封端ENPs与悬浮颗粒物之间的相互作用联系起来。将使用zeta电位和使用时间分辨动态光散射测量的聚集速率来评估ENP关于均聚的稳定性。NOM-AuNP相互作用将使用荧光和表面增强拉曼光谱进行探测。最后，金纳米粒子和悬浮胶体之间的相互作用将通过仪器中子活化分析的新应用进行量化。通过使用一组表征良好的ENPs，不同的只是相对于它们的表面功能，环境行为可以与ENP的结构活性类型关系的属性。这项工作将提供一个改进的能力，预测环境命运的基础上NP的特点，并产生必要的反馈设计更安全的纳米材料。更广泛的影响：拟议的工作是转型的，因为它的目的是移动该领域远离评估纳米材料的环境影响的个案基础上，并朝着发展的结构-活性类型的关系与纳米粒子特性的环境行为。预计这样的框架将可扩展到其他类别的纳米颗粒和环境过程，如沉积，氧化还原和溶解。该小组和其他人通过该项目所做的大量工作可能有助于开发预测环境转归和评估风险的改进模型。这项工作支持更安全的纳米材料和纳米制造计划的目标，PI是其中的一员，并将促进与俄勒冈州立大学和其他机构的同事合作。其他更广泛的影响将来自于博士教育所形成的人力资本。环境工程专业学生。外联、本科生教育和本科生研究机会将是拟议工作的一个组成部分。PI通过OSU现有的项目支持本科生研究的历史，这些项目专注于女性和少数民族学生的招聘。PI将继续通过在实验室接待高级项目团队、约翰逊学者（大学新生）和SESEY（高中）学生来指导本科研究人员。这些学生将成为有关工作的研究团队的一个组成部分。此外，PI将开发一个教育模块，专注于水处理的颗粒过滤，适合K-12和新生工程专业的学生，作为吸引学生参与环境工程领域的工具。