Multiarray Sensors for Real Time Detection of Microbial Metabolites in Watersheds and Sub-surface Systems

The Department of Energy is seeking the development of in situ real time measurement of microbial metabolites in subsurface environments and watersheds. In situ detection of microbial activity in submerged soils and aquatic sediments can be labor intensive and technically difficult. Data obtained from field-based studies will populate modeling-based output for accurate prediction of the water-energy nexus involved in the complex biogeochemistry. Current approaches for estimating anaerobic microbial activity involve incubating soil/sediment samples. Sophisticated analytical techniques are currently used which are not convenient and sometimes unsuitable for field deployment. Also, the labor and expense of such approaches often discourage the series of measurements temporally and spatially. This project’s portable carbon nanotube platform will quantitatively detect microbial metabolites in situ using a handheld reader with minimal user training. During the proposed project, the project team will develop a biosensor array with capture molecule-functionalized carbon nanotubes for in situ monitoring of microbial metabolites in subsurface environments. The sensor system will incorporate capture, detection, and response/readout technology. Unlikecurrenttechnologiesusedformicrobialsignature detection, this system eliminates the need for culture-based microbial growth, the addition of extraneous fluorophores, use of enzymatic signal amplification, or complicatedexperimental setup and data read out. In Phase I, the project team will: 1) fabricate multiplex electrode biosensor arrays, 2) construct capture molecule-grafted biosensor, 3) prepare chemostat growth cultures from soil sediments, 4) build a lab-based prototype and evaluate the prototype for detection of microbial metabolites. The result will be a compact, field-deployable rugged sensor with in situ monitoring capacity for rapid and sensitive detection of subsurface microbial signature. This multiplexed biosensor can be easily modified for detection of varied microbes and/or microbial signature depending on the need. The underlying technology has the capacity to detect a wide array of pathogens in situ andin real time. The global environmental monitoring market is projected to reach $25.5 billion by 2024, with a growth rate of 6.8% over $18.4 billion in 2019.