Analysis of amino acid mixtures by plasma desorption mass spectrometry

✍ Scribed by Yannik Hoppilliard; Christine Mauriac

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 560 KB
• Volume: 28
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/oms.1210280908

✦ Synopsis

Plasma desorption mass spectrometry (PDMS) was investigated as a means of analysing mixtures of three, four and five amino acids in both positive-and negative-ion modes. Fifteen mixtures were tested; each mixture contained equimolar amounts of selected amino acids. The PD mass spectra exhibited MH+ and [ M -HImolecular ions for all the aminoacids with different desorption-ionization yields. The spectra were more easily interpreted in the negative-than the positive-ion mode. The desorption order of the amino acids was progressively established by comparing the molecular ion desorption-ionization yields for each mixture. This desorption order was well correlated in both the positive-and negation-ion modes with the acid-base thermodynamic data for the amino acids in the gas phase. This observation gives some insight into the desorption-ionization mechanisms under PDMS conditions.