Advanced Fluorescence-Based Environmental Sensors

该提案旨在开发基于荧光的传感器，用于环境化学分析，包括汞、镉、氰化镍、硝酸盐、硫化物等。传感器包括用于过程和废水监测应用的遥感光纤。他们也可以被设计成手持和在现场工作中使用。在这两种情况下，传感器都比目前的技术有明显的优势，目前的技术主要是采样，然后在遥远的实验室进行后续分析。这些传感器是基于荧光的，并采用生物分子作为传感器元件，其中生物分子在识别目标化学物质时表现出其荧光寿命或各向异性的变化。为了优化传感性能，将使用位点定向诱变来开发生物分子的新变体。对于光纤传感器，生物分子将被整合到现有的传感器设备中进行测试。对于基于各向异性的传感器，申请人将构建一个新的固态微型荧光计。这种小型荧光计是供现场使用的。组件的额外进步可能使其精度提高一百倍，从而提高准确性和检测极限。拟议的努力具有三方面的意义。这些新型传感器旨在使过程水循环、废水流出和地下水的监测更简单、更安全、更精确、成本更低、自动化程度更高。改进后的传感器不仅可以使过程更高效、更安全，而且，就硝酸盐而言，它们可以减少农民的成本，并通过防止过度施肥来减少污染。这些新的传感器也可能足够精确，可以提供与当前环境保护署（EPA）标准方法相当的结果。

9613556 Thompson This proposal seeks to develop fluorescence-based sensors for chemical analytes of environmental interest, including mercury, cadmium, nickel cyanide, nitrate, sulfide, and others. The sensors incorporate optical fibers for remote sensing in process and wastewater monitoring applications. They can also be designed to be handheld and used in field work. In both cases the sensors offer significant advantages over current technology, which mostly involves sampling followed by subsequent analysis in a distant laboratory. These sensors are fluorescence-based, and employ a biomolecule as the transducer element in which the biomolecule exhibits a change in its fluorescence lifetime or anisotropy upon recognition of the target chemical. To optimize the sensing properties, site-directed mutagenesis will be used to develop new variants of the biomolecule. For the fiber optic sensors, the biomolecules will be incorporated into existing sensor apparatus for testing. For the anisotropy-based sensors, the applicants will construct a new solid state mini-fluorometer. The mini- fluorometer is intended for field use. Additional advances in components may enable it to achieve one hundred-fold better precision, and thereby improve accuracy and detection limits. The significance of the proposed effort is three-fold. These new sensors are intended to make monitoring of process water recycling, wastewater outflows, and ground water simpler, safer, more precise, less costly, and more automated. Improved sensors may not only make processes more efficient and fail-safe, but, in the case of nitrates, they may reduce the cost to the farmer and reduce pollution by preventing over-fertilizing. These new sensors also may be precise enough to provide results comparable with current Environmental Protection Agency (EPA) standard methods.