Gas chromatography and mass spectrometry of N-trifluoro-acetyl amino acid isopropyl esters

All primary α-amino acids detected in the Murchison Meteorite were also found in Miller's recent prebiotic synthesis of amino acids by electric discharge. A procedure was established that allows the separation and ready identification of these amino acids by gas chromatography-mass spectrometry. The retention times of the amino acids as their N-trifluoro-acetyl (N-TFA) isopropyl ester derivatives were determined in methylene units in comparison with a standard of aliphatic hydrocarbons on a SF-96 stainless steel needle stock. The mass spectra of the derivatized amino acids were taken and standardized. These standards have been recorded on magnetic tape and will be used for the computerized identification of mass spectra of N-TFA amino acid isopropyl esters from extraterrestrial or prebiotic samples to be investigated. The applicability of the method was tested on samples from a polymerization experiment of hydrogen cyanide received from J. P. Ferris. Five protein and two nonprotein amino acids were isolated, separated, and identified by gas chromatography in combination with mass spectrometry.