New Mexico Geological Society Annual Spring Meeting — Abstracts

The legacy of uranium mining in the southwestern United States has resulted in numerous Native American communities experiencing uranium (U) concentrations in their surface waters that exceed the EPA's Maximum Contaminant Level of 30 μg/L. Affordable and user-friendly field sensors for U detection are needed, as they could offer tribal communities direct methods for measuring contaminants in real-time, eliminating barriers that restrict current detection methods, like cost and the requirement for specialized operators. The objective of this study is to evaluate the use of a hand-held biosensing system, ANDalyze, that uses synthetic DNA in the form of DNAzymes to detect U. Surface water samples collected in April of 2024 and March of 2025 from a site affected by mining legacy were used to evaluate the accuracy of ANDalyze. When comparing the results of ANDalyze and Inductively Coupled Plasma Mass Spectrometry, we showed that ANDalyze consistently undervalued the U concentration in environmental samples. Based on troubleshooting information in the user manual, competing ions in natural waters may cause interference. Further water chemistry analysis reveals that the sulfate and carbonate levels in the surface water samples are sufficiently high to cause interference and limit the system's accuracy. Moving forward with further research into DNA-based sensors and developing a better understanding of the water chemistry of surface waters impacted by the mining legacy are important steps in ensuring the accuracy of these methods.