Optimization of Organic Molecule Separation and Detection Using Gas Chromatographic Column Based on MEMS Technologies Developed for Planetary and Exobiology Studies
Résumé
The work presented here aimed to explore functionalization and characterization of
square cross section channels of microchip columns for on board instruments for organic
molecule measurements in solar system.
First, the influence of the analytical set-up used to integrate our microchips have been
demonstrated and optimized to ensure the most real microchip performances and limit
extra-column effects. Thus, several junction capillaries, liner internal diameter and
detector parameters were compared and the best combination was chosen.
Then, the influence of stationary phase static coating method parameters was studied
by varying the coating velocity and the coating thickness. Efficiency measurement and
optical microscopy were used to compare microchips. Results showed that slowing down
the coating velocity improved the coating. Moreover, the efficiency and the retention
capacity of our microchips highly depend on the film thickness (10,000 ptx.m-a with k =
0.12 for the thinnest film up to almost 5,000 ptx.m-a with k = 0.93 for the thickest film) and
varied following the same trend as with conventional GC columns, which is a way to
validate our coating method on microchips.
Finally, we compared square cross section and circular cross section and both using
conventional GC fused silica capillaries. Result demonstrated the anticipated
complications of coating a stationary phase film on a square cross section