Microsensors in Icy Environments to Detect Microbial Activities

Electrochemical techniques such as impedance spectroscopy offer a non-invasive approach to monitor microorganisms in natural and engineered environments. Here, we present data on the use of microfabricated impedance spectroscopy sensors for the detection of microbes in icy environments. Under controlled laboratory settings, the effects of different cell concentrations of the Antarctic isolate Flavobacterium sp. ANT 11 on impedance spectroscopy was investigated at ambient temperature (22°C) and -10°C. Results show that varying cell concentrations of the bacterial isolate generate unique spectral responses that vary with temperature. Subsequent tests on the performance of microfabricated impedance sensors on natural microbial communities in icy environments in the Beartooth Mountains, WY, USA, confirmed laboratory findings. Different environmental samples at varying microbial concentrations in liquid, semi-frozen (slushy), or frozen states generated discrete impedance spectra. While caution is advised to generalize these results due to the potential contribution of unknown environmental variables, our data provide fertile territory for research in cryo-microbiology, as information on the applicability of impedance spectroscopy under frozen conditions is limited.