STTR Phase I: Development of low-cost optical sensor for nitrate detection in agricultural soils and environmental waters

该项目的更广泛影响/商业潜力将有助于控制土壤和水中的营养污染物，造福世界。为美国人口提供可持续的安全饮用水。据估计，饮用水中氮污染的全国经济成本为每年190亿美元，而淡水生态系统的成本为每年780亿美元。传统的水质监测方法是基于“采集样本”，送到实验室进行分析，可能需要几天到几周的时间才能完成。在农业中也发现了类似的传统方法，过量施用硝酸盐肥料可能导致农业径流，将污染带到地面和地表水来源。提出的高性能、低成本光学传感器技术将能够在淡水资源、水处理设施和农场部署密集的实时监测网络，并将在68亿美元的全球水质监测设备市场中获得重要的立足点。在发生自然灾害的情况下，拟议的硝酸盐传感器的集成将有助于评估当地水资源的水质，为社区提供有关水安全的实时信息。这项小型企业技术转让（STTR）第一阶段项目的重点是开发一种用于实时监测水中硝酸盐浓度的非色散红外（NDIR）探测器。这项工作将结合硝酸盐选择性离子交换膜技术和今天的低成本红外（IR）组件，设计一种针对水环境应用的新型传感器。该技术依靠红外光纤进行信号传输。目前，基于紫外线吸收的商用实时光学硝酸盐传感器的使用受到限制，因为与无机和有机物质相关的紫外光谱中的光学干扰，以及浊度导致的紫外线透射率降低。提出的专有红外技术旨在通过实现智能膜过滤来克服这些缺点。该仪器将在动态水环境中提供高频数据收集，具有宽灵敏度范围（1至100 ppm）。这项技术可以进一步扩展到测量额外的营养物质和污染物，使其成为水质评估的强大工具。

The broader impact/commercial potential of this project will be to help control nutrient contaminants in soil and water for the benefit of the world?s population, by providing sustainable access to safe drinking water. The estimated national economic cost of nitrogen pollution in drinking water is $19 billion annually, while the cost to freshwater ecosystems is $78 billion per year. Traditional water-quality monitoring practices are based on "grab-samples" that are sent for laboratory analyses that may take days to weeks to be completed. Similar traditional approaches are found in agriculture where excessive application of nitrate-based fertilizers may result in agricultural runoff that carries pollution to ground and surface water sources. The proposed high-performance, low-cost optical sensor technology will enable deployment of a dense real-time monitoring network in freshwater sources, water treatment facilities, and farms, and will gain a significant foothold in the $6.8B global water quality monitoring equipment market. In the event of natural disasters, integration of the proposed nitrate sensor will be useful in assessment of water quality in local water resources, providing communities with real-time information on water safety.This Small Business Technology Transfer (STTR) Phase I project focuses on the development of a non-dispersive infrared (NDIR) detector for real-time monitoring of nitrate concentration in water. This effort will combine nitrate-selective ion-exchange membrane technology with today's low-cost infrared (IR) components for the design of a new type of sensor targeting applications in aqueous environment. The proposed technology relies on infrared optical fibers for signal transmission. Currently, the use of commercial real-time optical nitrate sensors, based on ultra-violet (UV) absorption, is limited due to the optical interferences in the UV spectra related to the inorganic and organic substances, and reduced UV transmission caused by turbidity. The proposed proprietary IR technology is designed to overcome these shortcomings through implementation of smart membrane filtering. The instrument will provide high frequency data collection in dynamic aqueous environments with a wide sensitivity range (1 to 100 ppm). This technology can be further expanded for measurement of additional nutrients and contaminants, making it a robust tool for water quality assessment.