Synthetic Biology for Nuclear Activity Detection

Dan Park | 20-FS-009

Project Overview

The ability to detect uranyl fluoride through environmental monitoring would enhance the ability to identify and deter illicit nuclear weapons programs. However, current methods for uranyl fluoride detection have limitations that hinder adoption in wide-area or standoff nuclear monitoring. We posit that whole-cell biosensors offer promise for environmental nuclear monitoring given their potential for inexpensive, autonomous function. In a previous project, we developed a uranyl-responsive genetic circuit in the bacterium Caulobacter crescentus that enabled selective uranium detection in ground water samples. In this project, we optimized and integrated a fluoride-sensing functionality within this genetic circuitry to enable detection of soluble uranyl fluoride species. The resulting whole-cell biosensor exhibited a linear fluorescence response to uranyl fluoride particles and was unreactive with uranyl nitrate.

The successful demonstration of a bacterial-based uranyl fluoride sensor represents an important step in the development of an autonomous, biology-based, nuclear detection and monitoring platform, and the work provides a proof of principle that natural biological pathways can be leveraged for the detection of signatures associated with nuclear proliferation.

Mission Impact

We anticipate that this work will seed the development of technology that improves our nation's ability to monitor and flag suspicious facilities and regions for more in-depth characterization, ultimately enhancing nuclear nonproliferation efforts. In particular, the Lawrence Livermore National Laboratory's advanced materials and manufacturing core competency could be leveraged to build a miniaturized prototype of an integrated detection device (e.g., a 3D-printed microfluidic device). More broadly, we expect this combinatorial sensing approach to be generalizable and to drive the development of additional, biological-based modules for sense and respond functionality, which could be applied toward the detection and provision of countermeasures for chemical/biological threats. The knowledge and expertise gained in this project will also benefit mission-relevant work that is part of DOE's Biological and Environmental Research science focus area, including development of environmentally-constrained biocontainment circuits to safeguard against the unintentional environmental spread of genetically modified bacteria.

Publications, Presentations, and Patents

Park, D. 2020a. "Biosensors for detecting and/or neutralizing bioavailable uranium and related u-sensitive genetic molecular components, gene cassettes, vectors, genetic circuits, compositions, methods and systems." U.S. Patent Application 16/781,950.

——— 2020b. "Biosensors for detecting and/or neutralizing bioavailable uranium and related u-sensitive genetic molecular components, gene cassettes, vectors, genetic circuits, compositions, methods and systems. U.S. Patent Application 16/764,824.