Chemical Sensing Employing Bioluminescent Bacteria for Water Supply Systems

We present herein an optoelectronic bacterial chemical sensing system for monitoring on-location different materials in water supply systems which employ bioluminescent sensing bacteria (bioreporters) as its core sensing elements. The system exploits the capability to genetically engineer strains of bioreporters to sense any selected target material and report its findings by emitting bioluminescent photons. For employing them as technological entities, the bioreporters were encased in alginate capsules that provide them with the wet habitat and nutrients necessary for their existence. Special cassettes containing ensembles of capsules serve as the operational platforms that are incorporated in the optoelectronic sensing system. In concept, the system is a multichannel array of optoelectronic modules each containing a different strain of bioreporters genetically engineered to sense a different target material. Each module measures the bioluminescence emitted by capsules exposed to four distinct solutions, providing an indication of the presence and concentration of the selected target material in the inspected water sample. A single-channel prototype of the optoelectronic module was constructed, and its operation was tested with different bioreporter strains. Sensitivity of detection of 50 ppb and concentration accuracy of 12% in the inspected solution were demonstrated. The prototype was designed to be scaled up to a full-fledged multichannel sensing system that can be deployed in large numbers outdoors and provide on-location monitoring in water supply systems. In addition, the prototype constitutes a benchmark for employing bacterial sensing as the basis for a viable technology for performing chemical analysis in general.