SBIR Phase I: Development and Commercialization of Nitrate-Selective Sensors for Precision Agriculture

这个小企业创新研究（SBIR）第一阶段项目将展示概念验证，并验证将硝酸根阴离子分子受体转化为高选择性和灵敏度土壤探针的可行性。最终，这些传感器将满足在环境可持续的精准农业中实时监测施肥的需求。目前用于硝酸盐监测的离子选择性电极和化学改性场效应晶体管接口都只能在水介质中进行测量。这些传感器仅依赖于非特异性相互作用，由于一般缺乏硝酸盐选择性受体成分，它们的选择性。这一限制使其无法用于土壤介质中，在土壤介质中，高度竞争性的干扰物会降低响应。本文提出的第一个创新是开发一种传感器，该传感器结合了合理设计的和固有选择性的主体分子，这将提供对硝酸盐的亲和力，从而能够在分子水平上监测土壤。这项技术将实现第二项创新：一个可现场嵌入的土壤传感器网络，可以实时无线报告施肥过程中的肥料水平。这些创新将使土壤中的分子选择性传感成为可能，并将为未来分子传感器的开发铺平道路，用于监测复杂介质中难以靶向的阴离子和中性底物。该项目更广泛的影响/商业潜力是可持续地养活世界的简单需求。在未来30年内将粮食生产能力提高两倍，同时减少非点源污染对环境的影响，已被确定为科学面临的重大挑战之一。硝酸盐肥料占每年施用的2100万吨肥料的近60%，其中近30%由于渗漏，径流和挥发而浪费。 即使在最终导致非点源污染的250万吨国内肥料中节省20%，种植者每年平均每英亩可节省45美元，从而在美国产生价值约21亿美元的年度市场。此外，对土壤常量营养素的实时监测将通过提供这些化学物质的原位行为和归宿的快照来增强对土壤化学的理解。在全球范围内，开发一种低成本和通用的土壤质量探测器将为发展中地区提供一种优化产量和实现粮食生产自给自足的新方法。此外，这些传感器将通过基本解决方案解决地下水污染的环境困境：限制粮食、花卉和谷物生产中浪费性的过度施用肥料。

This Small Business Innovation Research (SBIR) Phase I project will demonstrate proof of concept and validate the feasibility of translating a molecular receptor for nitrate anion into a highly-selective and sensitive soil probe. Ultimately, these sensors will fulfill the need for real-time monitoring of fertilizer application in environmentally sustainable precision agriculture. Both the ion-selective electrode and chemically modified field effect transistor interfaces currently used for nitrate monitoring are capable of measurements only in aqueous media. These sensors rely solely upon non-specific interactions for their selectivity due to a general lack of nitrate selective receptor components. This limitation preempts their use in soil media where highly competitive interferents diminish response. The first innovation proposed herein is the development of a sensor incorporating a rationally designed and intrinsically selective host molecule, which will provide the affinity for nitrate needed to enable monitoring in soils on a molecular level. This technology will then enable a second innovation: a field-embeddable soil sensor network that wirelessly reports fertilizer levels during application in real-time. These innovations will enable molecularly selective sensing in soil, and will pave the way for the development of future molecular sensors for monitoring difficult-to-target anionic and neutral substrates in complex media.The broader impact/commercial potential of this project is the simple need for feeding the world sustainably. Increasing food production capacity by two-fold in the next 30 years, while concurrently decreasing the environmental impact of nonpoint-source pollution has been identified as one of the grand challenges facing the sciences. Nitrate-based fertilizer accounts for almost 60% of the 21M tons of fertilizer applied annually and almost 30% of this is wasted due to seepage, runoff and volatilization. Conserving even 20% of the 2.5M tons of domestic fertilizer that ultimately contribute to nonpoint-source pollution would save growers an average of $45/acre annually, giving rise to an annual market in the U.S. worth approximately $2.1B. Additionally, real-time monitoring of soil macronutrients will enhance understanding of soil chemistry by providing snapshots of the in situ behavior and fate of these chemicals. On a global scale the development of a low-cost and universal probe for soil quality would offer developing areas a novel method for optimizing yields and enabling self-sufficiency in food production. Additionally, these sensors will address the environmental dilemma of groundwater contamination with a foundational solution: limiting the wasteful over-application of fertilizers in food, flower and grain production.