Amino Acid Precursors from a Simulated Lower Atmosphere of Titan: Experiments of Cosmic Ray Energy Source with <sup>13</sup>C- and <sup>18</sup>O-Stable Isotope Probing Mass Spectrometry

DOI DOI IR IR IR (HANDLE) View 6 Remaining Hide 4 Citations 98 References Open Access
  • TANIUCHI Toshinori
    Department of Chemistry and Biotechnology, Yokohama National University
  • TAKANO Yoshinori
    Institute of Biogeosciences, Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
  • KOBAYASHI Kensei
    Department of Chemistry and Biotechnology, Yokohama National University

Bibliographic Information

Other Title
  • Amino Acid Precursors from a Simulated Lower Atmosphere of Titan : Experiments of Cosmic Ray Energy Source with ¹³C- and ¹⁸O-Stable Isotope Probing Mass Spectrometry

Search this article

Description

The organic haze of aerosols that shrouds the Saturnian moon Titan has previously been studied by both observations and laboratory simulation experiments. Here we report the abiotic formation of amino acid precursors in complex organic molecules during experimental simulation of the environment near Titan’s surface with proton irradiation. Pyrolysis of the organic molecules formed in the simulated Titan atmosphere by proton irradiation at 600°C yielded compounds that contained HCN and NH3 (m/z = 27 and 17). These experimental results are consistent with the molecular information obtained by pyrolysis gas chromatography/mass spectrometry (pyrolysis GC/MS) of samples collected by the Huygens probe to Titan. Scanning electron microscopy (SEM) and three-dimensional atomic force microscopy (AFM) images of the irradiation products reveal nanometer-scale filaments and globules in complex amorphous structures (approximately 1000 Da). Isotope probing experiments by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) show that oxygen atoms were incorporated into the racemic amino acids by hydrolysis of 18O-labeled water. We suggest that the amino acid precursors possibly formed after water hydrolysis, as suggested in a previous observational study (C. A. Griffith, T. Owen, T. R. Geballe, J. Rayner, and P. Rannou, Science, 2003, 300, 628). We propose that cosmic rays are a significant and effective energy source for producing complex organics and amino acid precursors in Titan’s atmospheric haze.

Journal

  • Analytical Sciences

    Analytical Sciences 29 (8), 777-785, 2013

    The Japan Society for Analytical Chemistry

Citations (4)*help

See more

References(98)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top