Development and Integration of an Ultraminiaturized\nGas Chromatograph Prototype Based on Lab-on-a-Chip Microelectromechanical\nSystems for Space Exploration Missions

We\ndeveloped, integrated, and tested an ultraminiaturized gas chromatograph\nprototype for space applications based on microelectromechanical system\n(MEMS) preconcentrator, column, and detector subunits. The fluidic\ninterface, the mechanical design, and the electronic system were all\ndesigned to be easily transposable to space instrumentation. The response\nlinearity, reproducibility as well as the preconcentrator, column,\nand detector performances were demonstrated using a mixture of <i>n</i>-pentane, <i>n</i>-hexane, benzene, and toluene.\nUsing the column, the response linearity of the nano-gravimetric detector\n(NGD) was observed over 1 to 2 orders of magnitude with a high <i>R</i><sup>2</sup> value of 0.99. The retention time reproducibility\nwas evaluated with a variation lower than 0.2%. The column separation\nperformances were also qualified in terms of number of theoretical\nplates (<i>N</i>) and height equivalent to a theoretical\nplate (HETP) with 8275 ± 45 plates (equivalent to 1655 ±\n9 plates per meter) and 0.6 mm on average, respectively. The preconcentrator\nperformance for trapping and desorption was also validated. The NGD\nshowed high sensitivity, and the limit of detection was evaluated\nto be about 3.1 pmol for toluene, which is very suitable for space\nexploration. The analytical performance of the first μGC-MEMS\nprototype was already satisfying and adapted for space studies. Nevertheless,\nsome ways of optimization were identified (like back-flush injection\nfor the preconcentrator or the use of valves more suited to space\napplications) to improve both performances and instrument robustness,\nand they will be tested in the future with a second version of our\nprototype.