Bioluminescent Bioreporter Integrated Circuits for Monitoring Spacecraft Environments

We are developing a family of microelectronic-based, whole-cell, bioluminescent biosensors that detect and quantify a number of compounds that threaten crew safety on future manned space missions. These devices are composed of genetically engineered bioluminescent bacteria deposited on a specially designed integrated circuit (IC) to form low-mass, low-power, very specific chemical sensing elements. We call these sensors bioluminescent bioreporter integrated circuits (BBICs). This technology offers many advantages over conventional chemical species detection/identification methods, including no requirement for optical excitation or focusing elements, direct compatibility with any local area network communications protocol, very low-power operation, and a common sensor platform that minimizes the number of required spares. Also, the whole-cell sensing system is completely self-contained such that no exogenous addition of reagents is required. Proof-of-principle experiments have been conducted with prototype BBICs that detect low parts-per-billion concentrations of toluene and naphthalene.
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In this work we will deploy a control bioluminescent strain on the IC to normalize the measurement from the sensing bioluminescent strain and also indicate the viability of the cells. We envision that the final embodiment of BBICs designed for the monitoring of spacecraft environments will fit in a volume of ~1 cm3, consume less than 100 microwatts of power, and be compatible with vapor or aqueous monitoring. We have developed bacterial bioreporters for the detection of amonia, and are making progress on the development of yeast bioreporters for environmental estrogens. We have developed encapsulation techniques for the bioreporters using sol-gel, PDMS, and latex. We have developed a single-chip microluminometer that has a photodetector leakage current of only 3 fA, and a quantum efficiency approaching 70%. An essential element required for the effective preservation and/or clean up of environmental sites is the ability to accurately and precisely measure specific environmental contaminants. Ones ability to do this is generally limited by the sensitivity and specificity of the biological and chemical sensors used to monitor the environmental site of interest. The research emanating from this research will provide significant improvements in the ability to measure environmental contaminants more accurately and precisely and at a much lower price than currently achievable. Also, by combining the biosensor technology with the IC technology, the potential now exists to create bioremediation sensors that will be capable of both sensing and remediating specific unwanted environmental hazards. In addition, these sensors will find applications in inexpensive medical diagnostics, food/water monitoring, and hazardous chemical detection and management.