This Small Business Innovation Research (SBIR) Phase I project proposes to develop a cell-free optical enzymatic biosensor for monitoring trichloroethene (TCE) concentrations in water. The biosensing concept will be implemented in an optical fiber format, in which optical biosensor tips are linked to a small electro-optical unit. Chemical detection takes place on biosensor tips that are coated with enzymes and fluorescent chemicals. In preliminary experiments, sensors using whole cells containing the desired enzymes were shown to measure TCE concentrations. However, those whole-cell sensors had limitations with respect to their detection limits and manufacturability. Thus, the research objectives of this project are to develop a cell-free version of this biosensor by extracting the necessary multicomponent enzyme and incorporating the enzyme onto the biosensor tips. Attainment of these objectives will advance the TCE-sensing technology toward a robust and readily manufactured system for TCE monitoring with improved detection limits, increased accuracy, and reliability.
The broader impact/commercial potential of this project, if successful, will be to increase the efficiency of identifying, mapping, and remediating water sources contaminated with TCE. Water use has been growing at more than twice the population rate. Both water quantity and water quality are becoming dominant issues in many countries. The necessity of monitoring aqueous-phase TCE concentrations will continue for many generations due to its widespread occurrence in water sources, its toxicity, and its high stability. A significant need exists and will continue to rise worldwide for devices that can measure the concentration of TCE as well as other chlorinated organic chemicals in water, and that can do so rapidly, accurately, and inexpensively. Continuous in-situ data production in the field of environmental sensing will greatly increase efficiency in all processes that require a measurement of TCE concentration. This sensor will allow for continuous monitoring of possible contamination sources in the case of a contamination event. Also, it will afford facile depth and spatial profiling of TCE plumes in aquifers. This technology will replace the current chromatography-based measurement protocols, which are not readily adapted for in-situ, on-line, or in-the-field measurements, and cannot produce data continuously.
The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I-IB project was to increase the efficiency of identifying, mapping, and remediating water sources contaminated with chlorinated solvents. Chlorinated solvents are used in vast quantities as solvents and degreasing agents, and in the dry cleaning industry. The necessity of monitoring chlorinated solvents in water will continue for many generations due to their widespread occurrence in water sources around the world, their toxicity, and their high stability. There is a significant need for devices that can continuously measure the concentration of chlorinated organic chemicals in water, and that can do so accurately and inexpensively. Continuous in-situ data production in the field of environmental sensing will greatly increase the efficiency of all activities that require measurements of these chemicals. Current laboratory-based measurement protocols are not readily adapted for in-place, on-line, or in-the-field measurements, and cannot produce data continuously. This SBIR project resulted in the development of a prototype optical enzymatic biosensor for continuous, quantitative monitoring of chlorinated solvent concentrations in water. The biosensing concept is implemented in an optical fiber format, in which optical biosensor tips are linked to a small electro-optical unit. Analyte detection takes place on biosensor tips that are coated with enzymes and fluorescent chemicals. The results of this project advanced the sensing technology towards a robust and readily manufactured system for chlorinated solvent monitoring with low detection limits, high accuracy, and reliability. The technical goals associated with the Phase I project were to extract, purify, and integrate into the OptiEnz biosensor, a suitable detection enzyme for making real-time continuous measurements of chlorinated solvents. The chlorinated solvent of interest was trichloroethene (TCE). OptiEnz achieved this goal, producing a sensor for TCE with detection capabilities suitable for the intended application. Phase IB of the project went further to explore technologies for application of a second enzyme to be used for monitoring mixtures of chlorinated solvents in ground water. The project was successful in providing the required preliminary research to move the chlorinated solvent sensor toward a marketable product. This sensor will beneficially impact the field of environmental remediation through an increase in availability of much needed data on contaminant concentrations in ground water. This will lead to an overall reduction in costs associated with cleaning up contaminated sites, and ultimately, greater access to clean water.
