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: 2224240
• 负责人: Robert McLean
• 金额: $ 3万
• 依托单位: Texas State University - San Marcos
• 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=2224240&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.

细菌以薄而粘稠的生物膜形式生长在几乎所有含水的物体表面，而水中存在的微生物只有不到 10% 存在于生物膜中，而生物膜会因藏匿病原体而对水质产生不利影响。例如嗜肺军团菌，它们可以释放回水中，或对水系统的运行产生不利影响（例如，介导表面腐蚀、减少传热、堵塞阀门或传感器）。生物膜存在并在医疗设备、工业制造和饮用水系统（包括宇航员所依赖的系统）中造成问题，例如，在国际空间站中，生物膜的形成会危及宇航服、水回收装置、散热器和导航窗等关键设备。控制生物膜的化学策略需要运输、储存和输入高强度消毒溶液，这可能会带来其他问题。该项目旨在了解和演示如何使用纳米纤维传递杀菌紫外线，其行为类似于。 “消毒荧光棒”，用于可能生长生物膜的表面，杀菌紫外线可以杀死任何粘附或生长在表面的细菌，尽管地球上和国际空间站的水系统中也生长着相同类型的细菌。太空中的重力会影响细菌群落的生长，研究小组将在地球和国际空间站上进行平行实验，以了解紫外线是否会因重力效应而对生物膜产生不同的影响。微重力与地球重力下的杀菌紫外线将增强我们创造健康人类栖息地的能力。研究小组将与高中生合作，通过一个由四部分组成的生物膜模块来解释生物膜在日常生活中的作用。使用纳米技术的无化学消毒解决方案。目前，生物膜对微重力下杀菌紫外线的敏感性尚不清楚，该项目涉及负责实体的太空科学促进中心。管理国际空间站国家实验室的实验将使用据报道存在于国际空间站水系统生物膜中的五种细菌来研究杀菌紫外线（265 至 285 纳米）对水系统中生物膜的抑制作用。国际空间站上的杀菌紫外线生物膜抑制实验将证明杀菌光对国际空间站水系统中使用的相关材料的生物膜形成的影响。极端环境（微重力）下的无化学物质、长期生物膜控制策略将与地球上其他相同的地面控制进行比较。了解微重力的影响很重要，因为一些细菌的生长和最终密度以及相关的生物膜形成。 ，与地球重力相比，微重力可能有所不同。 其次，将在装有不同类型纳米粒子装饰的侧发射光纤的充水反应堆中进行实验，以研究两种机制的影响。 （光解与氧化）以减轻生物膜形成 杀菌光由无汞发光二极管产生，进入独特的纳米技术光纤，直接附着在表面并侧面发射最先进的纳米材料、化学和生物光。将应用方法和模型来研究发光二极管操作的占空比，以减少功率需求，并相应地减少需要管理的热负荷，同时实现生物膜缓解。 PI 将开发并应用聚合酶链反应引物来识别组成菌群的每种细菌，以监测种群水平。此外，研究人员将使用共聚焦显微镜和图像分析应用定量荧光活力染色来评估紫外线照射下生物膜活力和结构的变化。更广泛的影响包括一个新的由四部分组成的生物膜模块，重点关注纳米技术实现的无化学解决方案，该模块将与高中教师以及公共宣传活动共同开发和使用，该项目将增进对生物杀灭处理效率发展的基本了解。微重力环境中的细菌生长和生物膜形成可能与地球不同，比较微重力和地球重力中的生物膜生长和对 UV-C 光的响应将提高我们创造健康人类栖息地的能力。该奖项是 NSF 的法定使命，并且已被授予。通过使用基金会的智力优点和更广泛的影响审查标准进行评估，认为值得支持。