Abstract - Emily Kurfman

Method Development for Analysis of Bacteria by Capillary Electrophoresis for Life Detection on Ocean Worlds

Emily A. Kurfman1,2, Maria F. Mora3, Peter A. Willis3, and Susan M. Lunte1,2,4

1Department of Chemistry, University of Kansas, Lawrence, KS, USA;  2Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA;  3Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA;  4Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA

Future space exploration missions would likely focus on ocean worlds, such as Europa (a moon of Jupiter) and Enceladus (a moon of Saturn), to search for life associated with their liquid water oceans. In order to be able to detect and profile the chemical composition of any single-celled life that might be found, cell analysis methods are needed that are compatible with spaceflight missions. These methods must be able to concentrate and lyse cells, and extract and analyze their metabolites using analytical methods that could be made suitable for spaceflight. As a result, we are developing hardware for concentrating and lysing cells with high voltage for analysis by capillary electrophoresis (CE) with multiple detection methods. CE is a separation method that is useful for analysis of small, charged biomolecules, and can be made portable for spaceflight. It is also compatible with various detection methods including UV-visible absorption spectroscopy, capacitively coupled contactless conductivity detection (C4D), and mass spectrometry (MS). A combined CE-C4D-UV method for biomolecules using a background electrolyte of 2 M acetic acid was developed for separation of positively charged biomolecules from cells, including amino acids and nucleobases, and this method was applied to analysis of E. coli cultures. Initially, standard methods were evaluated that could be used for comparison of extraction efficiency to our cell lysis devices. We extracted E. coli using several different solvents, including 80/20 methanol/water and 2 M acetic acid, showing that many analytes in cells can be extracted using these solvents and analyzed using our CE method. Additionally, 3D-printed devices are currently being prototyped to carry out cell concentration and lysis. In the future, CE-MS will be used with these lysis methods to provide more conclusive identification of cellular metabolites.