Fig. 1.

Gas chromatogram showing diamino acids identified in a sample of the Murchison meteorite (Mur). Data were obtained after hot-water extraction, 6 M HCl hydrolysis, and ECEE derivatization (2). Detection was in the single-ion monitoring mode of mass trace 175 atomic mass units (amu) typical for specific diamino acid derivatives. (Insets) External standard of the enantiomer separated diamino acids dl-2,3-diaminopropanoic acid and dl-2,4-diaminobutanoic acid (Std) purchased from Fluka and detected in the total ion current; a laboratory sample produced by UV-irradiation of circumstellar/interstellar ice analogues (ISM) under the conditions described in ref. 6 detected in the single-ion monitoring of mass trace 175 amu; and a serpentine blank (Blk) at mass trace 175 amu that had been heated before extraction for 4 h at 500°C and passed through the analytical protocol.