Development of SFE for sample return – SFERE

The SFERE project aims to improve the characterisation of extraterrestrial organic matter thanks to the development of supercritical fluid extraction (SFE) of extraterrestrial samples. These samples are precious and generally poor in organic matter. Also, this organic matter is usually strongly linked to the mineral matrices, therefore the extraction must be adapted. The SFE should limit the contamination and chemical evolution risks while increasing the recovery yield of the molecules of prebiotic interest: amino acids, carboxylic acid, sugars, etc. However, the extraction step is challenging and must be optimised. Some meteorites available on Earth will be the first objects to be studied followed by Mars analogues. To develop the extraction by SFE for each category of extraterrestrial object, it is necessary to optimise the various parameters of SFE (temperature, pressure, co-solvents, time of extraction…). The sample characterisation will be carried out by chromatography coupled to mass spectrometry (MS) and more particularly we wish to use on-line supercritical fluid chromatography (SFC) that will improve the separation of the molecules, thus their identification by MS. The optimised parameters will be validated by comparison against other extraction techniques (Soxhlet, ultrasons and ASE) .
The results will help the comprehension of organic matter complexification and prebiotic chemistry. This study comes within the scope of the sample return space missions that have developed strongly those past few years. On the long term, the development of a spatial instrument and its implementation on space missions could be contemplated in order to improve the in-situ characterisation.