Microbial Interactions with Biodegradable Polymer Nanocomposites that Incorporate Carbon Nanotubes

微生物与含有碳纳米管的可生物降解聚合物纳米复合材料的相互作用

• 批准号: 1236493
• 负责人: Howard Fairbrother
• 金额: $ 30万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-11-01 至 2016-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1236493&HistoricalAwards=false
• 关键词: Microbial; Interactions; Biodegradable; Polymer; Nanocomposites

This NSF award by the Environmental Health and Safety of Nanotechnology program supports multidisciplinary work by Professors Howard Fairbrother, Ed Bouwer and Seth Guikema to characterize the effect of microbial interactions with biodegradable polymers that incorporate carbon nanotubes (CNTs). Polymer nanocomposites containing CNTs represent an example of a next generation type of nanomaterial because of the beneficial effects that CNTs have on many polymer properties. However, following consumer use polymer nanocomposites will enter the environment where their ultimate fate and impact will be intimately dependent upon their interactions with microorganisms present in environmental regimes such as landfills, soils or surface waters. To better understand the life cycle of this new class of nanomaterials we plan to develop a systematic understanding of the persistence and fate of biodegradable polymer nanocomposites exposed to different microbial populations, including potential pathways for CNT release. Findings from these experiments will also be used as the basis to develop a risk-based decision making framework that can determine the most appropriate means for disposing of polymer nanocomposites. Such a proactive approach for risk assessment and life cycle analysis is necessary for new types of nanomaterials in the developmental stage. Intellectual Merit: The experimental design is to establish relationships that link important parameters, such as CNT loading, type and surface chemistry with biodegradation and biofilm accumulation rates and biotransformation mechanisms. Through this approach environments will be identified where CNTs could be released as particles from the solid phase composite and where biodegradable polymer nanocomposites could resist biodegradation and persist, in stark contrast to the behavior of the native polymer. The PIs will initially focus on preparing a selected suite of well characterized CNTs and CNT-containing biodegradable polymer nanocomposites where CNT type, surface chemistry, loading and the biodegradable polymer matrix will be varied. Using selected single and mixed culture populations to mimic different environmental regimes, microbial interactions with polymer nanocomposites and CNT particles will be explored by conducting three types of complementary experiments: (1) flow cell studies to evaluate attachment and biofilm accumulation on the surface of the polymer nanocomposites, (2) batch studies to quantify biodegradation and CNT release, and (3) isotopically labeled CNTs to determine the fate of CNT-carbon and potential CNT degradation mechanisms. Broader Impacts - This research will develop a fundamental and holistic scientific understanding of microbial interactions with CNT-containing biodegradable polymer nanocomposites, an emerging class of nanomaterial with enormous commercial potential. This information will also provide a predictive framework for the development of nanocomposites with material properties that have been engineered for positive social and economic consequences without long term industrial liability. The PIs will also provide research opportunities, guidance, and mentoring to female high school juniors through the Women in Science and Engineering program and female undergraduate students from the Notre Dame of Maryland University (a local, primarily teaching, women?s college). Additionally, the PIs and graduate students will give presentations in a pilot program, the City Springs Science Outreach Program, which focuses on enhancing scientific literacy and awareness for minority and underprivileged grade school students (5th grade) through exposure to hands-on science and engineering projects and activities.

这个由纳米技术计划的环境健康和安全NSF奖支持教授霍华德费尔兄弟，艾德鲍尔和赛斯Guikema多学科的工作，以表征微生物与生物可降解聚合物的相互作用，包括碳纳米管（CNT）的影响。含有CNT的聚合物纳米复合材料代表了下一代类型的纳米材料的一个例子，因为CNT对许多聚合物性质具有有益的影响。然而，在消费者使用之后，聚合物纳米复合材料将进入环境，其中它们的最终命运和影响将密切取决于它们与存在于环境体系（例如垃圾填埋场、土壤或表面沃茨）中的微生物的相互作用。为了更好地了解这种新型纳米材料的生命周期，我们计划对暴露于不同微生物种群的可生物降解聚合物纳米复合材料的持久性和命运进行系统的了解，包括CNT释放的潜在途径。这些实验的结果也将被用来作为基础，以制定一个基于风险的决策框架，可以确定最合适的手段处理聚合物纳米复合材料。对于处于开发阶段的新型纳米材料而言，这种积极的风险评估和生命周期分析方法是必要的。智力优势：实验设计是建立联系的重要参数，如碳纳米管负载，类型和表面化学与生物降解和生物膜积累速率和生物转化机制的关系。通过这种方法，将确定环境中的CNT可以从固相复合材料中释放为颗粒，并且可生物降解的聚合物纳米复合材料可以抵抗生物降解并持续存在，与天然聚合物的行为形成鲜明对比。PI最初将专注于制备一套精选的CNT和含CNT的可生物降解聚合物纳米复合材料，其中CNT类型，表面化学，负载和可生物降解聚合物基质将有所不同。使用选定的单一和混合培养群体来模拟不同的环境状况，将通过进行三种类型的互补实验来探索微生物与聚合物纳米复合材料和CNT颗粒的相互作用：（1）流动池研究以评估聚合物纳米复合材料表面上的附着和生物膜积累，（2）批量研究以量化生物降解和CNT释放，和（3）同位素标记的CNT以确定CNT-碳的命运和潜在的CNT降解机制。更广泛的影响-这项研究将发展一个基本的和全面的科学理解的微生物与含碳纳米管的可生物降解的聚合物纳米复合材料，一个新兴的一类纳米材料具有巨大的商业潜力。这些信息还将为纳米复合材料的开发提供一个预测框架，这些纳米复合材料的材料特性已被设计用于积极的社会和经济后果，而没有长期的工业责任。PI还将通过科学和工程项目中的女性和来自马里兰州圣母大学的女本科生（一个当地的，主要是教学，女性？s学院）。此外，PI和研究生将在一个试点项目中进行演示，城市温泉科学推广计划，重点是通过接触动手科学和工程项目和活动，提高少数民族和贫困小学生（5年级）的科学素养和认识。