Fiber Optic Sensors with Hydrophilic Radionuclide-Selective Cladding for the Detection of Radionuclides in Water Supplies

In this proposed Phase I program, we will develop a fiber optic scintillator system with a radionuclide-selective cladding for use in the detection of radionuclide contamination in water supplies or wastewater streams. The current terrorist threat requires that vigilance be maintained on all avenues of attack to the United States, including the potential for attack on the countrys food or water supplies. The major advantage of this technology relative to current off-site laboratory methods of detecting radionuclides in water systems is the instant on-site detection, which would allow for an appropriate and timely emergency response. Monitoring of radiological threats to water supplies is similar to the problem of monitoring groundwater contamination at Department of Energy facilities around the country. Significant challenges include the development of a robust detection system that can be used in a continuous monitoring mode and will be sensitive to extremely low levels of contamination. The selective scintillating fiber optic devices to be developed during this work are expected to be capable of real-time or on-demand analysis and also amenable to long-term and/or remote monitoring scenarios. When a large volume of scintillator is employed (either as a single fiber sensor or in sensor bundles) these systems should also be capable of providing detection levels corresponding to drinking water standards. In addition, the use of chemically selective pre-concentrating layers is expected to further improve the sensitivity and detection limits of the proposed sensor platform. Desirable attributes of these fiber-optic devices include small size, light weight, low cost, low power consumption, and easy integration into a wide variety of application environments. These devices would represent a significant improvement over the current baseline methods that are based on costly laboratory analysis procedures performed at centralized laboratories.