Extraction of amino acids from aerogel for analysis by capillary electrophoresis. Implications for a mission concept to Enceladus' Plume

Abstract

Ocean worlds like Europa and Enceladus in the outer solar system are prime targets in the search for life beyond Earth. Enceladus is particularly interesting due to the presence of a water plume ejecting from the south polar region. The recent discovery of H₂ in the plume, in addition to the presence of previously observed organic compounds, highlights the possibility of life in this moon. The plume provides materials from the underlying ocean that could be collected simply by flying through it. The presence of the plume means that material from the ocean is available for collection during a flyby, without the need for landing or complex sample handling operations such as scooping or drilling. An attractive approach to preserve the organics in particles collected during flyby encounters would be to utilize silica aerogel, the material used to collect particles at hypervelocity during the Stardust mission. Here we demonstrate amino acids can be extracted from aerogel simply by adding water. This simple liquid extraction method could be implemented during a mission prior to analysis with a liquid-based technique like capillary electrophoresis.

Keywords: In situ analysis; LIF detection; biosignatures; extraterrestrial exploration.