Application of TMAH thermochemolysis to the detection of nucleobases: Application to the MOMA and SAM space experiment

TALANTA

卷:204

Article

He, Y.¹  Buch, A.¹  Morisson, M.¹  Szopa, C.^2,3  Freissinet, C.²  Williams, A.⁴  Millan, M.^5,8  Guzman, M.²  Navarro-Gonzalez, R.⁶  Bonnet, J. Y.^2,7  Coscia, D.²  Eigenbrode, J. L.⁸  Malespin, C. A.⁸  Mahaffy, P.⁸  Glavin, D. P.⁸  Dworkin, J. P.⁸  Lu, P.⁹  Johnson, S. S.⁵ 

[1] Univ Paris Saclay, Cent Supelec, LGPM, 8-10 Rue Joliot Curie, F-91190 Gif Sur Yvette, France

[2] Sorbonne Univ, Univ Paris Saclay, UVSQ, CNRS,LATMOS IPSL, 11 Bd Alembert, F-78280 Guyancourt, France

[3] Inst Univ France, Paris, France

[4] Univ Florida, Gainesville, FL 32611 USA

[5] Georgetown Univ, Washington, DC USA

[6] Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, Ciudad Univ,Apartado Postal 70-543, Ciudad De Mexico 04510, DF, Mexico

[7] Telespazio France, Toulouse, France

[8] NASA, Goddard Space Flight Ctr, Greenbelt, MD USA

[9] Univ Paris Saclay, CEBB, SFR Condorcet FR CNRS 3417, LGPM,Cent Supelec, 3 Rue Rouges Terres, F-51110 Pomacle, France

关键词: Nucleobases;    Thermochemolysis;    Derivatization;    Pyrolysis;    GC-MS;    Tetramethylammonium hydroxide (TMAH);    SAM;    MOMA;   

DOI  :  10.1016/j.talanta.2019.06.076

来源: Elsevier

【 摘 要 】

Thermochemolysis of seven nucleobases-adenine, thymine, uracil, cytosine, guanine, xanthine, and hypoxanthine-in tetramethylammonium hydroxide (TMAH) was studied individually by pyrolysis gas chromatography mass spectrometry in the frame of the Mars surface exploration. The analyses were performed under conditions relevant to the Sample Analysis at Mars (SAM) instrument of the Mars Curiosity Rover and the Mars Organic Molecule Analyzer (MOMA) instrument of the ExoMars Rover. The thermochemolysis products of each nucleobase were identified and the reaction mechanisms studied. The thermochemolysis temperature was optimized and the limit of detection and quantification of each nucleobase were also investigated. Results indicate that 600 degrees C is the optimal thermochemolysis temperature for all seven nucleobases. The methylated products trimethyl-adenine, 1, 3-dimethyl-thymine, 1, 3-dimethyl-uracil, trimethyl-cytosine, 1, 3, 7-trimethyl-xanthine (caffeine), and dimethyl-hypoxanthine, respectively, are the most stable forms of adenine, thymine, uracil, cytosine, guanine, and xanthine, and hypoxanthine in TMAH solutions. The limits of detection for adenine, thy mine, and uracil were 0.075 nmol; the limits of detection for guanine, cytosine, and hypoxanthine were higher, at 0.40, 0.55, and 0.75 nmol, respectively. These experiments allowed to well constrain the analytical capabilities of the thermochemolysis experiments that will be performed on Mars to detect nucleobases.

【 授权许可】

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