RF-powered aqueous extractor for identification of chemical signatures of life on Mars, comets and asteroids

The prospect of finding chemical signatures of present or past life on Mars, comets, and asteroids is one of the important drivers behind NASA´s Solar System exploration program. A compact sample-processing technology that enables cataloging, characterization and accurate analysis of organic molecules and inorganic ions in planetary crustal materials is necessary to the success of in situ planetary exploration missions. We have been developing a series of compact microextractor (μEX) instruments that will address this necessity for in situ Mars exploration missions, sampling of cometary and asteroidal materials, and Mars Sample Return sample analysis. The core operational principle of μEX is based on a unique property of water - the ability to change its permittivity (i.e., dielectric constant) as a function of frequency. In our instruments, the dielectric constant of water decreases when 180 GHz frequency radiation (12 mW) interacts with samples inside the extraction channels. Recently, we started to transition our microextraction technology to a lab-on-chip scale, where the waveguide structure will be micromachined and integrated with 400-μm ID extraction channels. We have developed sample-manipulation procedures for injection of planetary-analog soil samples into microextraction channels and we have tested our sample-manipulation methods as a function of sample density (1.0 - 0.05 g/ml), sample mineral composition (e.g., conglomerate quatz, kaolinite, hematite, and smectite), and sample flow (1 - 400 μL/min). Here we present our research results, which include assembly and characterization of μEX operation^1,2.