SPLIce: A Microfluidic Sample Processor to Enable the Search for Life on Icy Worlds
Abstract
We will report the design, development, and laboratory testing of the Sample Processor for Life on Icy Worlds (SPLIce) system, a microfluidic sample processing "front end" to enable autonomous detection of signatures of life and measurements of habitability parameters on Ocean Worlds. Multiple versions of this monolithic fluid processing-and-handling system (mass 0.5 kg) are under development to support two nominal mission scenarios: a fly-through of Enceladus' icy plumes, which is expected to yield 2 μL of ice particles/m2 of collector area per pass at 20 km elevation, and a Europan lander, the drill-based sampling system of which is anticipated to deliver 1 - 5 mL of icy solids.The analytical instruments and sensors for which SPLIce sample preparation sequences are being explicitly tailored and developed include microchip capillary electrophoresis [1] combined with laser-induced fluorescence detection; mass spectroscopy detection [2] of samples following either derivatization and separation by gas chromatography, or separation by capillary electrophoresis; a suite of electrochemical sensors, including ion-selective electrodes [3]; and multiwavelength fluorescence microscopy. The SPLIce monolithic-manifold processes, distributes blanks, standards, controls, and samples by integrating a wide range of fluidic functions under autonomous control, including: 1) retrieval of fluid samples from a sample collection chamber; 2) onboard multi-year storage of dehydrated reagents, including fluorescent labeling compounds, contained in multiple isolated microchambers; 3) integrated pressure, pH, redox potential, and conductivity sensors; 4) filtration, retention, and fluorescent staining of insoluble sample fractions for characterization by microscopy; 5) dilution or vacuum-driven concentration of samples tailored to instrument detection capabilities; 6) removal of gas bubbles from fluid; 7) directional flow control; 8) active, multiple flow-path routing and 9) metered microvolume pumping. Current SPLIce design and prototype test results will be presented. Preliminary test results will be presented for these functionalities as implemented by the first laboratory. [1] Willis PA, Creamer JS, Mora MF. Implementation of Microchip Electrophoresis Instrumentation for Future Spaceflight Missions. Anal. Bioanal. Chem. 2015, 407, 6939-63.[2] Mahaffy PR, Webster CR, et al. The sample analysis at Mars investigation and instrument suite. Space Science Reviews. 2012,170, 401-78.[3] Kounaves SP, Hecht MH, et al. Wet Chemistry Experiments on the 2007 Phoenix Mars Scout Lander Mission: Data Analysis and Results. J. Geophys. Res. 2010, 115, E00E10.
- Publication:
-
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018
- Bibcode:
- 2018cosp...42E.634C