The First Complete SAM Wet Chemistry Experiment on Mars

International audience; Introduction: The Sample Analysis at Mars (SAM) instrument suite is currently operating in the Curiosity rover in Gale Crater, Mars. SAM carries nine sealed wet chemistry cups, seven which contain a mixture of N-methyl-N-(tert-butyldimethylsilyl) trifluoroacetamide and dimethylformamide (MTBSTFA:DMF 4:1) for derivatization and two that are filled with tetramethylammonium hydroxide (TMAH) and methanol for thermochemolysis [1]. Here we describe the first derivatization experiment performed on Mars with SAM that includes the puncture of one of the MTBSTFA cup. Overview of wet chemistry. One of the primary goals of the SAM investigation is the search for organic compounds on Mars. The wet chemistry cups onboard SAM are intended to make complex organic molecules more volatile derivatized products that can be readily analyzed by GCMS. An example of the MTBSTFA derivatization reaction with an amino acid is shown in Figure 1. The seven derivatization cups contain 0.5 mL of a mixture of MTBSTFA and DMF in a 4:1 ratio. These cups also contain trace standards (36.2 nmol of 3-fluorovaline and 24.2 nmol of pyrene) (Figure 1) for calibration and verification purposes.