Research Catalyst Grantee
Southern Utah University
Oxygen quantitation in anoxic waters and correlation to microbial life
Anoxic waters occur throughout the world, including fresh and salt water and man-made and -managed waters. Measuring the dissolved oxygen concentration in these waters can be crucial, and current methods are: easily contaminated, labor-intensive (titrations), insufficiently sensitive to accurately measure low dissolved oxygen concentrations (optical methods and the Clark electrode), and expensive and slow (the STOX electrode). We are developing a microfluidic device that should be similar in sensitivity to the STOX electrode, but significantly faster, more robust, and similar or slightly better in sensitivity. Currently we have developed a method to fabricate microfluidic devices amenable to the facilities available at Southern Utah University (SUU) and undergraduate researchers and have created several prototypes. The oxygen sensitivity of the devices has been demonstrated and the devices are being calibrated to determine their response to dissolved oxygen levels. The microfluidic devices will be field tested in two distinct and challenging environments. First, the device will be used to test dissolved oxygen levels in the Great Salt Lake -particularly in anoxic regions of the Great Salt Lake - in collaboration with Dr. Zachary Aanderud from Brigham Young University (BYU). Dr. Aanderud will continue his work with bacterial ecology of the Great Salt Lake, where dissolved oxygen levels are influenced by salinity and help structure ecosystem processes and microbial communities. The sensors will provide better oxygen data in these oxic and anoxic waters. The robustness of the microfluidics device will be tested by using them to measure dissolved oxygen concentrations in the complex low oxygen environment of a pig waste lagoon. In both cases, if the devices perform well, they will be used to map the dissolved oxygen levels as a function depth, and, to a limited extent, position. Employing the sensors in two (at least partially) anoxic bodies of water that are as different as the Great Salt Lake and a pig waste lagoon will provide an interesting study in the differences between anoxic waters with depth and help decipher bacterial responses to oxygen levels.
Zachary Aanderud, Brigham Young University
Kim Weaver, Southern Utah University
Lohra Miller, Southern Utah University
Emily Pehrson, Southern Utah University