Collaborative Research: ISS: Biofilm Inhibition with Germicidal Light Side-Emitted from Nano-enabled Flexible Optical Fibers in Water Systems

合作研究：ISS：水系统中纳米柔性光纤侧面发射的杀菌光抑制生物膜

• 批准号: 2224449
• 负责人: Paul Westerhoff
• 金额: $ 38万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-10-01 至 2025-09-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2224449&HistoricalAwards=false
• 关键词: Collaborative; Research; ISS; Biofilm; Inhibition

Bacteria grow on surfaces as thin, slimy biofilms in nearly anything that contains water. Over 90% of microorganisms present in water exist within biofilms, compared to less than 10% in the flowing water. Biofilms can adversely impact water quality by harboring pathogens, such as Legionella pneumophila, that can be released back into water, or adversely impact water system operations (e.g., mediating surface corrosion, reducing heat transfer, clogging of valves or sensors). Biofilms exist and cause problems in medical devices, industrial manufacturing, and drinking water systems, including those upon which astronauts rely. For example, in the International Space Station, biofilm formation jeopardizes key equipment including spacesuits, water recycling units, radiators, and navigation windows. Chemical strategies to control biofilms require transport, storage and input of high-strength disinfecting solutions that may bring other problems. This project aims to understand and demonstrate how germicidal ultraviolet light delivered using nano fibers, which behave like “disinfecting glowsticks”, to surfaces where biofilms might grow. The germicidal ultraviolet light kills any bacteria that stick to or grow on a surface. Although the same types of bacteria grow on Earth and in the water systems on the International Space Station, the lack of gravity in space can influence how bacteria communities grow, providing key insights. The research team will conduct parallel experiments on Earth and on the International Space Station to understand if ultraviolet light influences biofilms differently because of gravity effects. Comparing biofilm growth and response to germicidal ultraviolet light in microgravity versus earth-gravity will enhance our ability to create healthy human habitats. The research team will work with high school students, explaining the roles of biofilms in everyday life through a four-part biofilm module. This module will be developed using chemical-free disinfection solutions enabled by nanotechnology.Currently, the sensitivity of biofilms to germicidal ultraviolet light in microgravity is unknown. This project involves the Center for the Advancement of Science in Space, the entity responsible for managing the International Space Station National Lab. Experiments will study effects of germicidal ultraviolet light (265 to 285 nanometers) on the inhibition of biofilms in water systems using five bacterial species that reportedly are present in biofilms in International Space Station water systems. First, the germicidal ultraviolet light biofilm inhibition experiments on the International Space Station will demonstrate impacts of germicidal light on biofilm formation on materials relevant to those used in International Space Station water systems. The feasibility of this approach as a chemical-free, long-duration biofilm control strategy in an extreme environment (microgravity) will be compared against otherwise identical ground controls on Earth. The influence of microgravity is important to understand since the growth and final density of some bacteria, and associated biofilm formation, can differ in microgravity, as compared to earth gravity. Second, experiments in a water-filled reactor equipped with side-emitting optical fibers decorated using different types of nanoparticles will be operated under earth-gravity to study the effects of two mechanisms (photolysis versus oxidation) to mitigate biofilm formation. Germicidal light is produced from mercury-free light emitting diodes, which enters unique nanotechnology enabled optical fibers that attach directly on surfaces and side-emit ultraviolet light. State of the art nanomaterial, chemical and biological methods and models will be applied to study biofilms. Duty-cycling of light emitting diode operation will be studied to reduce power requirements, and correspondingly the thermal load that requires management while achieving biofilm mitigation. The PIs will develop and apply quantitative polymerase chain reaction primers to identify each bacteria comprising the consortia for monitoring population levels. Additionally, the researchers will apply fluorescent viability stain with confocal microscopy plus image analysis to assess changes in biofilm viability and architecture upon ultraviolet light exposure. The broader impacts include developing a new four part biofilm module focusing on chemical free solutions enabled by nanotechnology, that will be co-developed and used with high school teachers and in public outreach activities. The project will advance the fundamental understanding of biocidal treatment efficiency in microgravity environments, where bacterial growth and biofilm formation can differ as compared to Earth. Comparing biofilm growth and response to UV-C light in microgravity versus earth-gravity will advance our ability to create healthy human habitats.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.

细菌在几乎所有含有水的东西中都在表面上生长，粘稠的生物膜薄。在生物膜中，水中存在的微生物中有超过90％的生物存在，而流动的水中不到10％。生物膜可以通过含有病原体（例如肺炎军团菌）来对水质产生不利影响，这些病原体可以释放到水中，或不利地影响水系统的操作（例如，介导表面腐蚀，减少热传递，堵塞阀或传感器）。存在生物膜并在医疗设备，工业制造和饮用水系统中引起问题，包括宇航员所依赖的问题。例如，在国际空间站，生物膜形成危害包括太空服，水回收装置，散热器和导航窗的关键设备。控制生物膜的化学策略需要运输，存储和输入高强度消毒解决方案，这可能带来其他问题。该项目旨在理解并证明使用纳米纤维传递的杀菌紫外线如何表现到“消毒亮棒”，以使生物膜可能生长。杀菌紫外线可杀死任何粘在表面上或生长的细菌。尽管地球上和国际空间站的水系统中相同类型的细菌生长，但空间中缺乏重力会影响细菌群落的生长方式，从而提供关键的见解。研究小组将在地球和国际空间站进行并行实验，以了解紫外线是否因重力效应而对生物膜有所不同。比较生物膜的生长和对微生物与地球重力中杀菌紫外线的反应将增强我们创造健康人栖息地的能力。研究小组将与高中生合作，通过四部分生物膜模块来解释生物膜在日常生活中的作用。该模块将使用纳米技术启用的无化学消毒溶液开发。目前，生物膜对微重力中杀菌性紫外线光的敏感性尚不清楚。该项目涉及负责管理国际空间站国家实验室的实体太空发展中心。实验将研究杀菌紫外线（265至285纳米）对使用五种细菌物种在水系统中抑制生物膜的影响，据报道在国际空间站水系统中存在生物膜中。首先，国际空间站上的杀菌紫外线生物膜抑制实验将显示出对生物膜形成对与国际空间站水系统相关材料的影响。将这种方法作为极端环境（微重力）中一种无化学物质的长期生物膜控制策略的可行性与地球上其他相同的地面控制进行比较。由于某些细菌的生长和最终密度以及相关的生物膜的形成可能会有所不同，因此微重力的生长和最终密度在微重力上与地球重力相比可能有所不同，因此微重力的影响很重要。其次，在装饰有不同类型的纳米颗粒的侧面发射光纤的水填充反应器中进行的实验将在地球重力下进行，以研究两种机制（光解相对于氧化）的影响，以减轻生物膜的形成。杀菌灯是由无汞发光发射二极管产生的，该二极管进入独特的纳米技术，启用了直接连接在表面和侧面发射紫外线的光纤的纳米技术。纳米材料，化学和生物学方法和模型的最新状态将用于研究生物膜。将研究发光二极管操作的占空比以减少功率要求，并相应地，在实现生物膜缓解时需要管理的热负载。 PI将开发和应用定量聚合酶链反应引物，以识别每种细菌完成构成以监测人口水平。此外，研究人员将使用共聚焦显微镜以及图像分析应用荧光活力染色，以评估紫外线暴露后生物膜生存能力和建筑的变化。更广泛的影响包括开发一个新的四部分生物膜模块，该模块重点是纳米技术启用的无化学解决方案，该模块将与高中教师和公共外展活动共同开发和使用。该项目将提高对微重力环境中生物治疗效率的基本理解，与地球相比，细菌生长和生物膜形成可能有所不同。比较生物膜的生长和对微重力与地球重力中UV-C光的反应将提高我们创建健康人栖息地的能力。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子和更广泛的影响来审查标准，被认为是通过评估来获得的支持。