This proposed project will result in innovative instrument technologies that will enable order of magnitude improvements in NASA's capabilities in remote and in situ sensing. Recent developments in MEMS, microfluidics and nanotechnology provide the means to develop long-lived, invariant and reproducible reference electrodes. A major obstacle in using electrochemical sensors for remote and long term monitoring is the need for frequent calibration. The foremost cause of frequent calibration and maintenance is the variation in the liquid junction the interface between the reference electrode and the sample. The liquid junction is unavoidable in electrochemical sensors and is the major limiting factor in the accuracy and operational life of pH sensors, ion-selective electrodes and ORP monitors. This innovative reference electrode will extend the operating life of these sensors and eliminate the need for sensor recalibration and maintenance over their operating life. Electrochemical sensors using these reference electrodes will find application in planetary exploration, astrobiology, earth science and in long duration human space systems. It will provide a powerful tool for the remote monitoring of chemical, biological and environmental systems. The feasibility of developing an invariant and constant liquid junction will be demonstrated in Phase I.
Potential Commercial Applications:This innovative reference electrode will expand the use of electrochemical monitoring to remote and hazardous sites, and will result in lower cost and improved efficiency of chemical and biological processes. It will dramatically reduce maintenance requirements, increase efficiency, and decrease costs. In addition, because the technology prolongs sensor life and eliminates the need to recalibrate it will become the new standard for sensor performance.
