Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons

Details Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons

Dec 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994gecoa..58.5579p&link_type=abstract

Geochimica et Cosmochimica Acta, vol. 58, Issue 24, pp.5579-5587

Other

29

Scientific paper

The combined volatile bases (ammonia, aliphatic amines, and possibly other bases), ammonia, amino acids, and polar hydrocarbons were prepared from the Murchison meteorite for isotopic analyses. The volatile bases were obtained by cryogenic transfer after acid-hydrolysis of a hot-water extract and analyzed by combined gas chromatography-mass spectrometry of pentafluoropropionyl derivatives. The aliphatic amines present in this preparation comprise a mixture that includes both primary and secondary isomers through C 5 at a total concentration of 100 nmoles g - . As commonly observed for meteoritic organic compounds, almost all isomers through C 5 are present, and the concentrations within homologous series decrease with increasing chain length. Ammonia was chromatographically separated from the other volatile bases and found at a concentration of 1.1-1.3 mol g -1 meteorite. The ammonia analyzed includes contributions from ammonium salts and the hydrolysis of extractable organic compounds, e.g., carboxamides. Stable isotope analyses showed the volatile bases to be substantially enriched in the heavier isotopes, relative to comparable terrestrial compounds ( D + 1221%.; 13 C = + 22%.; 15 N = + 93%.). Ammonia, per se, was found to have a somewhat lower 15 N value (+69%.) than the total volatile bases; consequently, a higher 15 N (>93%.) can be inferred for the other bases, which include the amines. Solvent-extractable polar hydrocarbons obtained separately were found to be enriched in 15 N ( 15 N = + 104%.). Total amino acids, prepared from a hydrolyzed hot-water extract by cation exchange chromatography, gave a 15 N of + 94%., a value in good agreement with that obtained previously. Nitrogen isotopic data are also given for amino acid fractions separated chromatographically. The 15 N values of the Murchison soluble organic compounds analyzed to date fall within a rather narrow range ( 15 N = + 94 ± 8%.), an observation consistent with their formation, or formation of their precursors, by interstellar chemistry.

Affiliated with

Also associated with

No associations

Rating

Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1408382